back to indexThe Effects of Cannabis (Marijuana) on the Brain & Body | Huberman Lab Podcast #92
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Welcome to the Huberman Lab Podcast,
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where we discuss science and science-based tools
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for everyday life.
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I'm Andrew Huberman,
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and I'm a professor of neurobiology and ophthalmology
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at Stanford School of Medicine.
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Today, we are discussing cannabis,
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also referred to as marijuana.
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Cannabis includes many different compounds
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that have profound impact on the brain and body.
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So while many of you have probably heard of THC,
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there are also compounds in cannabis
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such as CBD, and of course there are different types
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or strains of cannabis, including sativa strains
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and indica strains and hybrid strains.
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And believe it or not,
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nowadays there is also an entire literature,
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meaning a scientific and medicinal literature
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about type one, type two, and type three strains.
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I'll explain what all of that is and how they work.
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I'll talk about some of the medicinal applications
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of different strains of cannabis
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and combinations of cannabis strains,
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as well as some of the potential health hazards
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I want to emphasize that any discussion about cannabis
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has to be framed within the context
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that the legality of cannabis varies tremendously
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depending on where you are in the world.
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So depending on which country you're in
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and even which state you're in
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or which area within a country,
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possessing and using and certainly selling cannabis
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can be either highly illegal or entirely legal
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or decriminalized or largely overlooked.
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You of course are obligated to know
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what those local laws are for you,
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where you live and where you travel.
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With that said, today's discussion really will include
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a full picture as to where cannabis
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and the various and even very specific compounds
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within cannabis can be extremely useful
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in the treatment of some ailments
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and where certain compounds in cannabis
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can be extremely dangerous for certain individuals to use,
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in particular individuals that have pre-existing
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genetic propensity for psychosis.
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That theme is going to come up again and again,
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but we are also going to talk about the role of cannabis
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in anxiety, in depression,
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both positive and negative effects.
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We'll talk about sex differences
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in terms of women versus men
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and how they react differently to cannabis.
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And I would be entirely remiss
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if I didn't include a conversation about cannabis,
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meaning THC, CBD, hybrid strains, et cetera,
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in creativity and different modes of thinking.
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Because as many of you probably know
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or at least have heard about,
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cannabis can impact the way that we think,
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the types of memory systems we can access
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and what's called convergent and divergent thinking,
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which is one way of conceptualizing
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what is commonly referred to as creativity.
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So today's discussion is going to include
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a lot of information,
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but I promise to make it clear and accessible to all of you,
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regardless of whether or not
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you have a background in biology or not.
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And today's discussion will also be quite nuanced.
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You'll find me routinely reading
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directly from specific research papers,
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something that of course we always do on this podcast.
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But today I'm really going to dig into
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some of the finer points of the methodology in papers
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and some of the statistics that were used
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and the specific populations of people that were studied.
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Because as it turns out,
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there are instances that we will discuss
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in which the use of cannabis
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can be immensely beneficial to one group
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and yet can be entirely detrimental to another group,
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even at equivalent dosages
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and depending on a number of different factors.
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So we will discuss what those factors are.
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Just to give you a brief overview
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of the kind of structure I'm going to put on today's episode,
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we will review, of course, cannabis and its various forms.
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I'll talk about some of the biology,
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but we are going to really drill into how dosage,
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that is the concentration of THC relative to CBD,
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impacts whether or not cannabis
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is going to have one effect or another.
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We will also talk about the frequency of use,
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daily use, multiple times per day use,
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weekly use or monthly or occasional use.
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We will also talk about different professions
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and how some people may have a little bit more leeway
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in terms of whether or not they decide to use cannabis
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or any of its various component chemical constituents,
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that is CBD or THC, et cetera.
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And for other professions,
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it might be entirely inappropriate
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because of the particular kinds of cognitive tasks
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those professions demand.
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We will also talk about genetic predisposition,
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again, sex differences, hormone effects.
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And I will also touch on
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what I think is the most important variable
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in determining whether or not cannabis
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is right or wrong for you.
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And that is your age at which you are considering
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starting or continuing use or ceasing use.
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What I can assure you is that by the end of today's podcast,
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you will have a quite thorough understanding of cannabis,
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how it works, what it does,
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what its potential benefits can be,
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what its potential hazards are,
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and whether or not it's right for you
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and the people that you know.
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I'm excited to announce that the Huberman Lab Podcast
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has now launched a premium channel.
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The purpose of the premium channel is several fold.
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First of all, I will be hosting regular AMAs,
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Ask Me Anythings, where you can ask me anything,
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and I will provide answers in depth
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to your specific questions about science
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and science-related tools for mental health,
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physical health, and performance.
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Now, there is a nominal cost to the premium channel.
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It's $10 per month, or you can pay $100 for the entire year.
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I should mention, however,
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that a significant portion of the funds
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raised through the premium channel
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are going to support not just the Huberman Lab Podcast,
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which we will continue to release every Monday on schedule,
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of zero cost to all consumers,
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content on mental health, physical health, and performance,
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but proceeds from the premium channel
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will also be used to fund research,
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in particular, research done on human beings,
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so not animal models, but on human beings,
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which I think we all agree is a species
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that we are most interested in,
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and we are going to specifically fund research
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that is aimed toward developing further protocols
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for mental health, physical health, and performance,
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and those protocols will be distributed
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through all channels, not just the premium channel,
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but through all channels, Huberman Lab Podcast
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and other media channels.
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So the idea here is to give you information
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to your burning questions in depth
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and allow you the opportunity to support
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the kind of research that provides those kinds of answers
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in the first place.
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Now, an especially exciting feature of the premium channel
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is that the Tiny Foundation has generously offered
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to do a dollar-for-dollar match
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on all funds raised for research through the premium channel.
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So this is a terrific way that they're going to amplify
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whatever funds come in through the premium channel
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to further support research for science
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and science-related tools for mental health,
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physical health, and performance.
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If you'd like to sign up
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for the Huberman Lab premium channel,
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again, there's a cost of $10 per month,
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or you can pay $100 upfront for the entire year.
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That will give you access to all the AMAs.
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You can ask questions and get answers to your questions,
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and you'll, of course, get answers to all the questions
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that other people ask as well.
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There will also be some premium content,
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such as transcripts of the AMAs
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and various transcripts and protocols
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of Huberman Lab podcast episodes not found elsewhere.
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And again, you'll be supporting research
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for mental health, physical health, and performance.
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You can sign up for the premium channel
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by going to HubermanLab.com slash premium.
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Again, that's HubermanLab.com slash premium.
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Before diving into all of that,
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I'd like to highlight a new,
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what I think is very useful and zero-cost resource.
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This resource is what's called non-sleep deep rest,
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I've talked many times before on the Huberman Lab podcast
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about non-sleep deep rest, AKA NSDR.
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NSDR is sort of an umbrella term
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for a variety of different practices.
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So these are behavioral practices
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that allow you to direct your brain and body
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into a particular state.
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And most typically, that state is one of deep relaxation,
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but also one in which you can access your bodily
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and brain systems for teaching yourself
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how to relax in real time
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and how to recover some of the sleep
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that you may not be getting at night
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and to restore levels of dopamine
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in particular areas of the brain
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that are involved in motivation
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and cognitive and motor control.
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Basically, NSDR is a wonderfully restorative tool.
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This has been demonstrated many times over now
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through quality peer-reviewed science.
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And there are neurochemical benefits
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and there are physical benefits
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and there are certainly psychological benefits.
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I highly recommend NSDR to anybody
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that has trouble falling asleep
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or that wakes up in the middle of the night
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and needs to get better at falling back asleep,
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as well as to anyone out there
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that has issues with anxiety
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or sort of self-regulation of any kind.
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And if you don't have any of those issues,
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it's also immensely beneficial just as a restorative
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for leaning back into focus work of any kind.
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Now, a number of people have reached out
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about finding NSDR protocols
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and there are a number of different good ones out there
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I've decided to put a zero cost NSDR script
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out there on the internet for people to access.
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So you can find it by going to YouTube
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and simply put my last name Huberman and NSDR
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into the search function.
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This is a YouTube channel that's hosted by Virtusan,
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which has a terrific app that includes NSDR
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and a number of other health and wellness protocols.
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But they've been quite generous
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in hosting a 10 minute NSDR read by me.
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This NSDR is distinct from,
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although I should say similar to Yoga Nidra,
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which some of you are familiar with.
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This NSDR is different than Yoga Nidra
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in the sense that it doesn't have intentions,
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there's no mystical component.
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And I describe a little bit of the science
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and why specific components of the NSDR included,
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things like long exhale breathing,
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I talk about perceptual shifts
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and how to move from thinking and planning
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to pure sensation.
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If none of that makes sense right now,
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it'll make total sense after listening to the NSDR script.
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Again, it's a 10 minute NSDR script read by me.
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You can do this first thing in the morning when you wake up,
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especially if you didn't get enough sleep that night
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and you're feeling a little bit fatigued
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and you need to lean into the day with full vigor.
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You could do it at any point during the day,
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or if you wake up in the middle of the night.
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Again, this is a zero cost resource for you.
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You can find it by going to YouTube,
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put my last name in, and NSDR.
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I encourage you to try it.
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And if you like it, or frankly, if you don't,
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you can just put that in the comment section
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And I've put it there as a free resource to you
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so that you can benefit from the research-backed,
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peer-reviewed studies that point to NSDR
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as a very useful practice.
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Before we begin, I'd like to emphasize
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that this podcast is separate
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from my teaching and research roles at Stanford.
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It is, however, part of my desire and effort
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to bring zero cost to consumer information
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about science and science-related tools
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to the general public.
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In keeping with that theme,
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I'd like to thank the sponsors of today's podcast.
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Our first sponsor is Levels.
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Levels is a program that lets you see
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how different foods affect your health
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by giving you real-time feedback on your diet
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using a continuous glucose monitor.
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One of the most important factors
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in your immediate and long-term health
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is how well you're managing your blood glucose
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I started using Levels about a year ago
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as a way to see how different foods
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and different lifestyle factors
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were impacting my blood glucose levels.
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So for instance, it allowed me to see how different foods
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and particular macronutrients
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and combinations of macronutrients
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would either peak or trough my blood sugar
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or keep my blood sugar steady.
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It also allowed me to see how working out
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with weights or running, how that impacted my blood glucose.
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So for me, it was a fascinating experiment
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unto myself as to how my meal schedule,
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the specific foods I was eating,
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different combinations of food, as I mentioned before,
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and exercise were combining to regulate
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this thing that we call blood sugar
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and that's so vital to our health.
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I think anyone that tries Levels
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will find that you learn an immense amount
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about what you're doing
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and what you ought to be doing differently
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in order to optimize your immediate feelings of wellbeing
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and your health trajectory.
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If you're interested in learning more about Levels
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and trying a CGM yourself,
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go to levels.link slash Huberman.
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That's levels.link, L-I-N-K slash Huberman.
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Today's episode is also brought to us by Thesis.
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Thesis makes custom nootropics
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that are designed for your particular needs.
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I am not a fan of the word nootropics
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because nootropics literally means smart drugs
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And frankly, as a neuroscientist,
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I know and every other neuroscientist knows
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that there is no neural circuit
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or chemical in the brain for being smart.
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There are, for instance, neural circuits and chemicals
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that increase your ability to focus
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or your ability to task switch.
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Thesis understands this
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and therefore has designed custom nootropics
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so that, for instance,
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if you want to achieve focus and clarity
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for one particular type of work,
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Or if you'd like to have more energy and have more focus,
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there's a different nootropic for that.
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If you'd like to get
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you can go online to takethesis.com slash Huberman,
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take that three-minute quiz,
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and Thesis will send you four different formulas
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to try in your first month,
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and then they'll work with you
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for you to take ongoing.
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Again, that's takethesis.com slash Huberman
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and use the code Huberman at checkout
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to get 10% off your first box.
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Today's episode is also brought to us by Inside Tracker.
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Inside Tracker is a personalized nutrition platform
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that analyzes data from your blood and DNA
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to help you better understand your body
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and help you reach your health goals.
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I've long been a believer in getting regular blood work done
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for the simple reason that many of the factors
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that impact your immediate and long-term health
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can only be analyzed with a quality blood test.
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With a lot of blood tests and DNA tests out there, however,
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an issue is you get information back
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about lipids and hormones, et cetera,
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but you don't know what to do with that information.
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With Inside Tracker, they have a personalized platform
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that makes interpreting your data
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and then acting on that data very straightforward
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and very directed toward specific protocols.
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What I mean by that is you'll get information back
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about hormone levels and metabolic factors, lipids, et cetera,
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and then you can look to nutritional changes,
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supplementation changes, exercise protocol changes,
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and other lifestyle features that combine
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or work on their own to try and shift those numbers
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into the range that's appropriate for you.
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If you'd like to try Inside Tracker,
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you can visit insidetracker.com slash Huberman
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to get 20% off any of Inside Tracker's plans.
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Just use the code Huberman at checkout.
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Again, that's insidetracker.com slash Huberman
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to get 20% off and use the code Huberman at checkout.
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On many episodes of the Huberman Lab Podcast,
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we talk about supplements.
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While supplements aren't necessary for everybody,
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many people derive tremendous benefit from them.
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Things like enhancing sleep and the depth of sleep,
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or for enhancing focus and cognitive ability,
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or for enhancing energy or adjusting hormone levels
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to optimal range for you.
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The Huberman Lab Podcast is now partnered
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with Momentus Supplements.
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We partnered with Momentus for a number of important reasons.
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First of all, the quality of their ingredients
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is exceptional, it's really second to none.
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Second of all, they ship internationally,
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and that was important to us because a number of you reside
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outside of the United States.
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Third, we've worked with Momentus very closely
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to develop single ingredient formulations.
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Now, this turns out to be very important
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because if you're going to take supplements,
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you want to know what's working for you and what isn't.
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And of course, you want to optimize the cost efficiency
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and the biological efficiency of those supplements.
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To find the supplements we discuss
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on the Huberman Lab Podcast,
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you can go to Live Momentus, spelled O-U-S,
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livemomentus.com slash Huberman.
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And I should just mention that the library
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of those supplements is constantly expanding.
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Again, that's livemomentus.com slash Huberman.
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Let's talk about cannabis.
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And when we refer to cannabis,
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we are indeed referring to marijuana or the marijuana plant.
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Now, cannabis plants come in different strains
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or different varieties, and those different strains
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are indeed different genetic strains.
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So just as animals and humans
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have different genetic backgrounds
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and they can be crossed to one another
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to yield further genetic variation in the offspring,
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plants can be hybridized to one another in various ways
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through grafting or through the use
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of different types of seed combinations, et cetera,
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in order to generate different strains.
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There are also naturally occurring differences
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in the strains of plants,
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and the cannabis plant is no exception.
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So for instance, in the context of a discussion
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about cannabis and its medicinal uses and recreational uses,
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we need to distinguish between the sativa variety,
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the indica variety, a variety called ruderalis,
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that's not often discussed,
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and hybrids of sativa, indica, and ruderalis.
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Before diving into the different strains of cannabis
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and how they impact the brain and body
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both similarly and differently,
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I want to emphasize that the cannabis plant
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contains a number of different psychoactive compounds.
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Now, the most powerful of those compounds is THC.
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The technical name for it is delta-9-tetrahydrocannabinol,
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but THC, as I'll refer to it,
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is just one of the psychoactive
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and biologically active compounds within cannabis plants.
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which is technically referred to as cannabidiol,
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and cannabidiol, CBD,
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is known to be used for things like pain management,
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anxiety management, and other medicinal purposes.
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We will talk about the efficacy of CBD for those purposes,
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as well as some of, believe it or not,
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some of the dangers of CBD,
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depending on where it's sourced and the dosage, et cetera.
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So we've got THC, CBD,
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and also CBN or cannabidiol.
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CBN is less often discussed.
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You're going to hear a lot less
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about CBN-containing products out there,
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CBN-containing medicines,
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but it is relevant to today's discussion,
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so it will come up a bit.
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Now, I will be sure to provide more specificity
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to what I'm about to say,
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but very broadly speaking,
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THC is largely responsible
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for the psychoactive effects of cannabis.
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That is the changes in mood,
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the changes in bodily state and sensation, et cetera.
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Whereas CBD, and to some extent CBN,
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have profound effects on the brain and body,
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but they don't tend to give people the sensation
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of altered perception, altered mood, et cetera.
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Some people might say they are not the component of cannabis
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that quote unquote gets you high.
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Although today we will really drill
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into what the high itself represents
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in terms of chemical systems in the brain and body.
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And what we will soon learn is that
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what we think of as being high
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actually includes a number of different changes
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in the brain and body,
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some of which can be best explained by CBD, not by THC,
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which runs counter to what most people out there
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So broadly speaking, we have THC, CBD, and CBN,
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but I want to point out that the cannabis plant
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has over 70, seven zero, 70 different psychoactive compounds
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many of which still have not been studied
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in isolation and in detail.
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So there's a big future of research for cannabis
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and for THC and THC related psychoactive compounds
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as well as for CBD and CBN.
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Today we're mainly going to focus on THC and CBD
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as I mentioned before.
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I should also point out that the cannabis plant
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has over 400 biologically active compounds.
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So these are biologically active compounds
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that may or may not have psychoactive properties
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that may or may not be useful for pain relief, et cetera.
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Again, there is a vast landscape for exploration
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of the cannabis plant and of hemp for what they include
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that could be beneficial to us or detrimental to us.
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So again, a lot more work to do.
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Today we're going to really try and stay on target
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with what we already know
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and where there are certain exciting mysteries
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or intriguing mysteries about what we ought to explore
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more I will certainly highlight those.
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Let's go back to the different strains of the cannabis plant
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sativa, indica and ruderalis
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and explore how each of those differentially impacts
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the brain and body because they're in
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I think we can start to learn a lot
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about this incredible plant that is the cannabis plant.
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And whether or not you are a user of cannabis
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or whether or not you are entirely opposed to cannabis use
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understanding how cannabis works in the brain and body
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itself is absolutely fascinating and can teach you a lot
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about how your brain and body work at a basic level.
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And can tell you a lot about how your brain and body
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will react to different life events
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and how your mood is established and stabilized
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and how your appetite is established and stabilized
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So we have the three major strains of cannabis,
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sativa, indica and ruderalis.
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And for sake of today's conversation,
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we can pretty much cross off ruderalis.
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It's not often consumed
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and components of ruderalis are not often consumed
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for medicinal recreational purposes.
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Let's focus on sativa and indica.
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People will consume the sativa variety of cannabis
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either by edible or by smoking cannabis
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or they will consume the indica variety of cannabis again
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by edible or by smoking cannabis
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or sometimes they will take it in a transdermal form
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or a sublingual form.
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There are a bunch of different ways to get the cannabis
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But there's a clear distinction between sativa and indica
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that actually shows up first in the structure of the plant.
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At their extremes, meaning in a pure strain of sativa,
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it tends to be a taller plant, a longer stock,
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believe it or not.
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And actually the length of the leaves
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is quite a bit longer.
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Whereas the indica plant tends to be more short and stout.
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And for those aficionados out there,
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I'm sure you know a lot of the other specific features
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of sativa versus indica.
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But already what we're talking about is the same plant,
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cannabis, with two very different morphologies or shapes.
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You might say, well, why is this interesting or important
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to how it affects me or affects other people
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for medicinal recreational purposes?
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Well, it turns out that even though they are the same plant,
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these two different genetic varieties,
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because of the way that they grow
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and the way they capture sunlight
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and the way, believe it or not,
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that the different plants within that strain
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interact with one another,
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because believe it or not,
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plants are interacting with one another,
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they actually bring different elements
link |
of the psychoactive compounds to different components
link |
within the leaves and the so-called buds.
link |
The takeaway is that when consumed,
link |
and when I say consumed, I want to be very clear,
link |
I don't necessarily just mean oral consumption
link |
or eating cannabis sativa by edible.
link |
I also mean smoking it,
link |
and that could be people will, just like with tobacco,
link |
the way that they bring the psychoactive components
link |
into their bloodstream and into their brain and body
link |
is to essentially heat the dried leaves
link |
of the cannabis plant.
link |
Then the heat liberates some of the psychoactive components
link |
that when inhaled into the lungs,
link |
because the lungs include a lot of vasculature,
link |
a lot of basically blood vessels and capillaries,
link |
that the psychoactive components are actually
link |
directly absorbed from the lungs into the bloodstream,
link |
and they can cross into the bloodstream
link |
and permeate throughout the body
link |
and cross the so-called blood-brain barrier.
link |
So in other words, burning the plant liberates the smoke
link |
that contains the psychoactive compounds,
link |
and those are inhaled into the lungs
link |
and then get into the brain and body
link |
and act on the brain and body.
link |
And the major effect of sativa varieties
link |
are to create a high, if you will,
link |
and I'm putting this in air quotes
link |
for those of you that are listening,
link |
but to also act as a stimulant.
link |
The sativa varieties tend to make people
link |
feel kind of invigorated, somewhat alert.
link |
It doesn't tend to be as much of a sedative
link |
as some of the other varieties.
link |
Some people report heightened sense of focus
link |
or heightened sense of creativity.
link |
We will talk a little bit later on
link |
as to whether or not they actually are achieving
link |
heightened levels of focus and creativity,
link |
or whether or not they just perceive themselves
link |
to have heightened levels of focus and creativity.
link |
The sativa varieties tend to make people
link |
feel a little bit less susceptible
link |
to pain and noxious stimuli,
link |
which are basically stimuli that you don't like.
link |
So the sativa varieties are often prescribed
link |
or are used in the recreational context
link |
for pain management and relief.
link |
Basically, the sativa variety is known
link |
to include a sort of head-biased effect.
link |
So here we're talking about subjective effects,
link |
and of course, these will vary
link |
from one individual to the next.
link |
Some people will smoke cannabis sativa
link |
or ingest cannabis sativa orally,
link |
and will feel an entirely different array of effects,
link |
but most people, the majority of people,
link |
experience a sort of head-centered high alertness focus
link |
and a sense that they're more creative.
link |
Contrast that with the indica varieties of cannabis,
link |
and when people smoke or eat or ingest indica varieties,
link |
the psychoactive components of indica,
link |
and again, this is pure indica,
link |
so not hybridized with sativa at all,
link |
but just pure indica,
link |
tend to lead to more full-bodied effects.
link |
People report feeling more complete full-body relaxation,
link |
more of a sedative effect.
link |
Indica cannabis is often prescribed
link |
and or used recreationally
link |
in order to achieve a state of sleep
link |
or to help relieve anxiety,
link |
so less of a stimulant effect,
link |
and we will talk about why,
link |
literally the underlying neural circuits,
link |
that lead to the sativa variety
link |
causing more of a elevated mood and a head high, if you will,
link |
and the indica varieties being more full-body relaxation.
link |
One of the ways to remember the distinction
link |
between the effects of cannabis sativa and cannabis indica
link |
was relayed to me by a friend
link |
who actually was a chronic, meaning every day, all day,
link |
consumer of marijuana.
link |
He basically smoked marijuana for 20 years
link |
before quitting about four or five years ago,
link |
and he said that indica is often referred to as indicouch,
link |
meaning laid back in the couch,
link |
and that can help you remember
link |
that the indica varieties of cannabis
link |
do tend to be more sedative in their effects.
link |
Okay, so there's sativa and there's indica,
link |
and then now there are hybrid strains.
link |
So marijuana growers and people who specialize
link |
in creating novel varieties of the cannabis plant,
link |
again, I'm using the words cannabis and marijuana
link |
more or less interchangeably here,
link |
they are very good at creating new strains of plant
link |
that might be 25% sativa and 75% indica or vice versa,
link |
or 50-50 or 90-10.
link |
Essentially what's happening nowadays
link |
is that through plant biology, plant genetics, I should say,
link |
growers are getting quite efficient
link |
at creating a variety of different strains
link |
of the marijuana plant that give rise to very nuanced
link |
and distinct effects on brain and body.
link |
In fact, so much so that there's now a new nomenclature,
link |
a new language emerging around cannabis
link |
and the development of novel strains of cannabis
link |
for medicinal and or recreational purposes.
link |
And while this might sound a little bit medical
link |
or a little bit clinical to some people,
link |
believe it or not, this is the nomenclature
link |
that it's now typically used.
link |
People still refer to the sativa, indica,
link |
and hybrid strains, but there's now also a description
link |
of so-called type one, type two, and type three strains
link |
for any given sativa, indica, or hybrid strain.
link |
Okay, so just to put this clearly in your mind,
link |
you've got sativa varieties, that is pure sativa varieties.
link |
You have indica varieties, again, pure indica,
link |
and then you have hybrid varieties.
link |
And beneath each of those, you have type one, type two,
link |
and type three strains of indica, sativa,
link |
or hybrid varieties.
link |
What are type one, type two, and type three?
link |
Well, type one, type two, and type three strains
link |
are strains that have varying amounts
link |
or ratios of THC to CBD.
link |
So for instance, type one strain.
link |
So for instance, you could have a pure sativa type one
link |
or a type one pure sativa, or a type one indica.
link |
Those are going to have the greatest amount
link |
of THC relative to CBD.
link |
And I really want to emphasize this,
link |
understanding the ratio of THC to CBD
link |
can help explain a lot or even predict a lot
link |
about how a given strain of cannabis will impact somebody.
link |
For instance, because THC is largely responsible
link |
for the typical psychoactive components of cannabis,
link |
so what I mean here is if somebody is ingesting sativa
link |
and it routinely makes them feel more energized,
link |
elevates their mood,
link |
gives them a heightened sense of creativity.
link |
If that's what they experience
link |
and they're taking a type one version of that,
link |
that means that it's quite rich in THC and very little CBD.
link |
However, if they were to take a type one version of sativa
link |
and it feels far too strong, like too much energy,
link |
or they felt like they were too much in their head,
link |
nowadays, there are strains of sativa
link |
that have been genetically engineered.
link |
And I don't mean by an engineer tinkering away
link |
with gene engineering in a kind of CRISPR creating mutants,
link |
but literally by hybridizing,
link |
crossing different plants to one another, okay?
link |
Creating in a natural context,
link |
the same way plants in the outside world
link |
would sometimes hybridize to one another.
link |
Creating a variety that's perhaps type two,
link |
which is going to have less THC and more CBD,
link |
or a type three, which is going to be very high CBD
link |
and very little THC.
link |
And the same is also true for the indica varieties.
link |
So I want to make sure that everyone understands this
link |
because it becomes very important
link |
for understanding the biology of cannabis
link |
and predicting positive versus negative effects of cannabis.
link |
Sativa has this kind of stimulant-like effect
link |
and tends to be more of a head high, if you will.
link |
Indica tends to be more full body than lead to more
link |
in the couch, as I referred to it before, pun intended.
link |
Deep relaxation, reduced insomnia, et cetera.
link |
Now within each of those, sativa and indica,
link |
you have type one, type two, and type three.
link |
And that has everything to do with how much THC,
link |
which is the dominant psychoactive compound versus CBD,
link |
which has other effects mainly on the body,
link |
but not so much on the brain and modes of thinking
link |
and mood, et cetera.
link |
How much THC versus CBD is present.
link |
And again, type one is THC dominant,
link |
type two kind of equal ratios, if you will,
link |
of THC and CBD, and type three tend to be high CBD.
link |
Okay, so already we've got some categorization here
link |
that hopefully isn't overwhelming to you,
link |
but this turns out to be extremely important
link |
if you want to understand how cannabis works
link |
and predict the effects of cannabis.
link |
I'd like to take a quick break
link |
and acknowledge one of our sponsors, Athletic Greens.
link |
Athletic Greens, now called AG1,
link |
is a vitamin mineral probiotic drink
link |
that covers all of your foundational nutritional needs.
link |
I've been taking Athletic Greens since 2012,
link |
so I'm delighted that they're sponsoring the podcast.
link |
The reason I started taking Athletic Greens
link |
and the reason I still take Athletic Greens once
link |
or usually twice a day is that it gets me the probiotics
link |
that I need for gut health.
link |
Our gut is very important.
link |
It's populated by gut microbiota
link |
that communicate with the brain, the immune system,
link |
and basically all the biological systems of our body
link |
to strongly impact our immediate and long-term health.
link |
And those probiotics in Athletic Greens are optimal
link |
and vital for microbiota health.
link |
In addition, Athletic Greens contains a number
link |
of adaptogens, vitamins, and minerals that make sure
link |
that all of my foundational nutritional needs are met
link |
and it tastes great.
link |
If you'd like to try Athletic Greens,
link |
you can go to athleticgreens.com slash Huberman
link |
and they'll give you five free travel packs
link |
that make it really easy to mix up Athletic Greens
link |
while you're on the road, in the car,
link |
on the plane, et cetera.
link |
And they'll give you a year's supply of vitamin D3K2.
link |
Again, that's athleticgreens.com slash Huberman
link |
to get the five free travel packs
link |
and the year's supply of vitamin D3K2.
link |
Okay, so somewhat surprisingly,
link |
we're going to set aside cannabis.
link |
We're going to take what we know about sativa, indica,
link |
type one, type two, type three, CBD, et cetera.
link |
We're just going to set that aside for a moment.
link |
Why would we do that?
link |
Well, we have to ask ourselves,
link |
why would any of these plants,
link |
why would any of these compounds, THC, CBD, sativa,
link |
indica, et cetera,
link |
why would any of that have any effect on us at all?
link |
And this discussion that we're about to have
link |
very much resembles the discussion
link |
that we had on a previous episode about nicotine.
link |
Because as many of you know,
link |
nicotine is a commonly used substance.
link |
In fact, if we were to look at
link |
the three most commonly used drugs,
link |
alcohol will be the top of the list.
link |
Many billions of people regularly use alcohol
link |
or occasionally use alcohol.
link |
Many billions of people also use nicotine.
link |
It's the second most consumed drug.
link |
So more than 1 billion
link |
and probably closer to 2 billion people consume nicotine.
link |
And then the third most consumed drug is cannabis
link |
in one form or another.
link |
And many of you are probably shouting,
link |
what about caffeine?
link |
What about caffeine?
link |
Well, in the context of drugs
link |
and in particular addictive drugs,
link |
caffeine doesn't quite rise to the list.
link |
But if we were to look at caffeine
link |
and include in that list,
link |
caffeine would be above all of those, okay?
link |
But the most commonly used drugs are alcohol.
link |
Second after that is nicotine and then cannabis.
link |
Nicotine, as some of you may know,
link |
if you listen to the episode on nicotine,
link |
but even if you didn't,
link |
nicotine comes from the tobacco plant.
link |
And there are a few other plants that include nicotine.
link |
And typically it's brought into the brain and body
link |
by smoking tobacco, dipping tobacco,
link |
snuffing tobacco or vaping nicotine.
link |
Nicotine exists in the outside world in these plants,
link |
the tobacco plants.
link |
But the reason it has an effect on the body
link |
is that there are so-called nicotinic receptors
link |
Now those nicotinic receptors
link |
were named after nicotine, the compound,
link |
but they existed in the brain and body,
link |
not because of the existence of a tobacco plant,
link |
but because there are other chemicals in the body
link |
that naturally occur, namely acetylcholine
link |
that bind the nicotine receptor.
link |
Those chemicals such as acetylcholine
link |
that bind the nicotinic receptor in your brain and body
link |
create an enhanced sense of focus, et cetera, et cetera.
link |
But nicotine from tobacco binds that same receptor,
link |
but with much greater affinity
link |
and therefore also creates a state of focus,
link |
but a much greater one than we can achieve without nicotine.
link |
Okay, so you can see the nicotine episode
link |
if you want to learn more about that.
link |
In a very similar way,
link |
all of our brains and bodies
link |
from the time that we are conceived,
link |
believe it or not, very shortly after conception,
link |
if we want to be accurate,
link |
very early conception when you were in the womb,
link |
and still now, if you're listening to this,
link |
you have what are called cannabinoid receptors
link |
because you also have endogenous cannabinoids.
link |
What do we mean by that?
link |
You have receptors which are like little parking spots
link |
that are present on cells in your brain and body,
link |
and what we call a ligand,
link |
which is basically just a chemical that's released,
link |
parks in that receptor,
link |
and causes a number of different biological effects.
link |
Cannabis contains compounds
link |
that also bind to those receptors,
link |
but here I want to make a really clear distinction.
link |
We have what are called endogenous ligands,
link |
those that just mean chemicals from within us
link |
that we make naturally,
link |
even if we never go near the cannabis plant
link |
or any other source of cannabis,
link |
we have chemicals that are created in us
link |
that park in those receptors and cause biological effects
link |
on mood, on perception, on the immune system,
link |
on hunger, et cetera.
link |
Again, without ever going anywhere near cannabis,
link |
we have these endogenous cannabinoids.
link |
So endogenous cannabinoids are floating around in us,
link |
or I should say they are released in us in particular ways,
link |
bind to these receptors
link |
and cause changes in mood, appetite, et cetera.
link |
They have many different effects on the brain and body.
link |
We will talk about those.
link |
But just like with nicotine,
link |
there are substances in the outside world,
link |
in this case, cannabis contains these substances,
link |
so things like THC and like CBD,
link |
that when ingested by smoking or vaping
link |
or by ingesting edibles,
link |
also will park in those same receptors,
link |
the cannabinoid receptors, and lead to biological effects.
link |
Now it's a little bit misleading
link |
because we call them cannabinoid receptors
link |
as if they were there to bind cannabis,
link |
or just like we call the nicotine receptors
link |
nicotinic receptors,
link |
it makes it seem as if they were there
link |
in order to bind nicotine from tobacco.
link |
But that's not the way our brains and bodies evolved.
link |
Our brains and bodies evolved for these receptors
link |
to make use of chemicals that exist within us
link |
called, again, endogenous chemicals.
link |
And those endogenous chemicals lead to certain effects,
link |
as I mentioned before.
link |
The key thing here,
link |
if you haven't understood anything I've said up until now,
link |
please understand this.
link |
The key thing is that THC and CBD
link |
and the other components of cannabis
link |
bind to those receptors,
link |
those endogenous cannabinoid receptors,
link |
the ones that we naturally make,
link |
with much greater affinity
link |
and exert a vastly greater potency
link |
and effect on mood and perception, et cetera,
link |
than do our endogenous cannabinoids.
link |
Another analogy that one could take
link |
in order to understand this
link |
would be hormones like testosterone and estrogen.
link |
Many people, I would say all people,
link |
make testosterone and estrogen to varying degrees.
link |
It's going to depend on whether or not you're male, female,
link |
your age, whether or not you've gone through puberty,
link |
et cetera, et cetera.
link |
But let's just say testosterone, for example.
link |
There's testosterone circulating in your body.
link |
That's true if you're male or female.
link |
And there are receptors called androgen receptors.
link |
We could even call them testosterone receptors.
link |
And the testosterone binds to those receptors
link |
and has effects on cells.
link |
It causes hair growth, changes the voice.
link |
It can affect libido.
link |
It affects all sorts of things in the brain and body,
link |
depending on which organ and tissue you're talking about.
link |
But of course, there are people
link |
that take synthetic testosterone
link |
or derivatives of testosterone.
link |
And some of those derivatives, for instance,
link |
in the bodybuilding community and the sports community,
link |
they will take things like Diana Ball.
link |
These are modified versions of testosterone
link |
that can bind to the testosterone receptor
link |
with much greater affinity, or I should say,
link |
the androgen receptor with much greater affinity
link |
and have supra physiological effects,
link |
effects that would essentially never be seen
link |
from testosterone that was endogenously,
link |
excuse me, endogenously released within the body.
link |
We could say the same thing for estrogen.
link |
There are estrogen receptors.
link |
They bind estrogen, okay?
link |
But if someone were to take synthetic estrogen
link |
or to ingest a plant compound
link |
that contains various estrogenic compounds,
link |
and those plants certainly exist out there,
link |
they can have supra physiological effects
link |
on those receptors.
link |
Why am I telling you this?
link |
Well, many people believe that because cannabis,
link |
marijuana is a plant and plants grow out of the ground
link |
and they're naturally occurring,
link |
and because we have receptors in our body
link |
that are there without the need to engineer them
link |
from some external source, right?
link |
They're in our genome, they program for it,
link |
and we're born with these things,
link |
and we keep these our entire life.
link |
Many people mistakenly think, ah, you know,
link |
these plant compounds are safer for us or better for us
link |
or are somehow appropriate for us to ingest,
link |
but that's simply not true.
link |
And here, I'm not saying that cannabis
link |
is always a bad idea for people.
link |
There are certain populations and certain people
link |
for which it can be relatively safe recreationally.
link |
And there are other populations
link |
for which it can be downright dangerous,
link |
recreationally or medicinally.
link |
And of course, there are medicinal purposes
link |
that are being explored, and we'll talk more about that.
link |
But this is vital to understand
link |
because I think that when we hear,
link |
oh, it's from a plant, it's natural,
link |
and then you also have a receptor for these,
link |
endogenous cannabinoid receptors,
link |
and therefore the marriage of those two, right?
link |
The coming together of the chemical, THC or CBD or both,
link |
with these receptors is somehow supposed to happen
link |
as if this was a purpose of having these receptors,
link |
but it's simply not the case.
link |
In the same way that the nicotinic receptors
link |
are not there because nicotine is good for us.
link |
They're there because there are compounds
link |
that exist within us that are good
link |
to bind to those receptors from time to time.
link |
Now, here's the key thing about,
link |
I guess today I'm saying there are a lot of key things,
link |
but here's another key thing about understanding cannabis
link |
and the way that it works,
link |
which is that THC and CBD,
link |
when they're brought into the brain and body
link |
by smoking or edible, et cetera,
link |
they bind to those receptors,
link |
those endogenous cannabinoid receptors,
link |
and they tap into the same systems
link |
that your endogenous cannabinoids would tap into,
link |
the ones that affect mood and energy and creativity
link |
and relaxation, et cetera,
link |
but they do so with thousand fold greater potency.
link |
And as a consequence of that,
link |
your endogenous cannabinoids are out competed.
link |
They really get no opportunity
link |
to interact with those receptors.
link |
And understanding that can lead
link |
to a very clear understanding of why, for instance,
link |
when people use cannabis to relieve anxiety
link |
or they use cannabis to enter a certain brain state
link |
for creativity or to enter sleep,
link |
why a dependence on cannabis starts to emerge,
link |
because if they don't ingest cannabis,
link |
and again, ingest could mean smoke,
link |
to bring THC in or CBD in or ingest orally
link |
or even transdermal or tincture
link |
or one of the other varieties,
link |
if they don't do that,
link |
then what happens is not only are the receptors
link |
not stimulated to the same degree
link |
or with the same potency that they normally are,
link |
but the endogenous cannabinoids
link |
can no longer have their effect.
link |
So people experience heightened levels of anxiety,
link |
disrupted mood, disrupted brain state, and so on.
link |
Now, again, I want to be very clear
link |
that I'm not trying to paint a picture of cannabis
link |
as all bad or even partially bad.
link |
What I want to do today is give you as much information
link |
I can as to how cannabis works,
link |
how its different component parts work,
link |
how the different types of cannabis work,
link |
and point to some of the valid medicinal uses
link |
and some of the recreational uses,
link |
and then lay out the landscape for you
link |
as to who is really most at risk
link |
in terms of psychoactive components,
link |
immune components, and so on and so forth
link |
so that you can make the most informed choice for you.
link |
I am not here to tell you what to do or what not to do.
link |
As I like to say, do as you wish, right?
link |
I mean, don't do as you wish
link |
if it harms other people or yourself,
link |
but do as you wish, but know what you're doing.
link |
So that's really my goal here.
link |
So as we begin to dive further into the biology,
link |
I think you'll start to get a clearer picture
link |
of why cannabis is so effective in some contexts,
link |
but also why it can create such massive suffering
link |
in other contexts because of the way that it out-competes
link |
your own natural endogenous cannabinoid systems.
link |
So let's talk about those endogenous cannabinoid systems,
link |
what they are and how they work,
link |
because that will give us a lens
link |
into what the higher potency,
link |
sort of maximum impact of the various cannabis plant
link |
varieties and strains and THC and CBD and so forth,
link |
how and why those work.
link |
So what are the endogenous cannabinoids,
link |
these chemical substances that everybody makes?
link |
You make them, I make them.
link |
You've been making them
link |
basically from the time that you were conceived
link |
and you are going to make them until the time that you die.
link |
Whether or not they have the impact
link |
and the biological functions that I'm about to describe
link |
will depend a lot on whether or not
link |
you are using your own endogenous cannabinoids
link |
to park in those receptors that you also have
link |
from birth until death,
link |
or whether or not you are tickling those receptors
link |
or strongly activating those receptors
link |
using some external source like cannabis, THC, et cetera.
link |
The two main endogenous cannabinoids
link |
that we want to consider are anandamide,
link |
which we will refer to as EAE.
link |
So anandamide and another one,
link |
which is arachidinoyl glycerol, arachidinoyl glycerol,
link |
which we will abbreviate 2AG.
link |
So let's just take EAE and 2AG,
link |
lump them together and talk about the endogenous cannabinoids
link |
just to make it simple.
link |
But if you want to do the deep dive on anandamide
link |
versus 2AG, please be my guest.
link |
The endogenous cannabinoids are released from neurons.
link |
Neurons are nerve cells,
link |
and nerve cells should be conceptualized like this.
link |
You have presynaptic neurons and postsynaptic neurons.
link |
Presynaptic neurons basically contain little vesicles,
link |
little bubbles full of neurotransmitter,
link |
which are chemicals.
link |
And when neurons are stimulated electrically,
link |
and that could be from a thought,
link |
it could be from the desire to move,
link |
it could be because of a drug,
link |
it could be because you're hungry,
link |
the relevant neurons will vomit out or will fuse,
link |
as we say, those little packets,
link |
those little bubbles of neurotransmitter
link |
into the gap between the pre and postsynaptic neuron.
link |
We call that a synaptic cleft or the synapse.
link |
It's a little gap, a little space.
link |
And the neurotransmitter flows across that synapse,
link |
and some of it will park in little parking spots
link |
that we call receptors on the postsynaptic neuron side.
link |
Depending on which neurotransmitter it is,
link |
and a bunch of other things,
link |
not worth going into right now,
link |
the parking of that chemical
link |
in those neurotransmitter receptors
link |
will either cause that neuron on the postsynaptic side
link |
to itself release neurotransmitter elsewhere,
link |
or it will quiet it down,
link |
so-called excitation and inhibition.
link |
That's kind of neurotransmission in a nutshell.
link |
If you don't understand it, no big deal.
link |
It's not going to prevent you
link |
from understanding today's discussion.
link |
If you understand even a small fraction
link |
of what I've just said,
link |
then it's going to allow you to understand
link |
not just today's discussion, but a lot of neuroscience
link |
with a lot more nuance and depth of understanding.
link |
The key thing to know about the endogenous cannabinoids
link |
is that unlike most neurotransmitters,
link |
they are released from the postsynaptic side.
link |
So what happens is neurotransmitter
link |
goes from presynaptic neuron to postsynaptic neuron,
link |
but under certain conditions,
link |
the postsynaptic neuron itself releases a chemical,
link |
and that chemical goes backward,
link |
what we call retrogradely, to the presynaptic neuron,
link |
binds the receptors there,
link |
and changes the probability that the presynaptic neuron
link |
will release neurotransmitter.
link |
Put simply, endogenous cannabinoids
link |
tend to decrease the probability
link |
that a neuron will release neurotransmitter.
link |
They are sort of a brake on the system.
link |
They are a way of shutting down
link |
the communication between neurons, regulating it,
link |
not to make it completely quiet,
link |
but to adjust the levels with a lot of nuance.
link |
Now, the other thing that the endogenous cannabinoids do
link |
is sort of a mind-bender
link |
because we're talking about cannabis,
link |
and a commonly known feature of cannabis
link |
and marijuana consumption
link |
is disruptions in short-term memory,
link |
and there is essentially zero debate
link |
as to whether or not that occurs,
link |
and we'll talk about the mechanisms a little bit later,
link |
and yet endogenous cannabinoids,
link |
the chemicals that you naturally release
link |
from these postsynaptic neurons
link |
that travel retrogradely back to the presynaptic neuron,
link |
actually can lead to strengthening of connections
link |
between the presynaptic neuron and the postsynaptic neuron
link |
through a process called long-term potentiation, or LTP.
link |
They can also cause what's called depression
link |
of communication between a presynaptic neuron
link |
and a postsynaptic neuron.
link |
Long-term depression has nothing to do
link |
with depression as a psychological state or as a illness.
link |
Long-term potentiation and long-term depression
link |
simply refer to the probability
link |
that one neuron will be able to stimulate
link |
and activate another neuron,
link |
and as I just told you, the endogenous cannabinoids
link |
can either turn up the dial or turn down the dial.
link |
They can either increase the probability
link |
or decrease the probability
link |
that a given connection between neurons
link |
will function more or will function less.
link |
So if you think about the communication between neurons
link |
as a crosstalk, as a conversation,
link |
well, the endogenous cannabinoids
link |
can dictate whether or not that conversation
link |
is likely to occur or not to occur.
link |
Think of them as either putting someone
link |
at the top of your text chain in your phone,
link |
which would be long-term potentiation,
link |
or essentially blocking their number,
link |
which would essentially be long-term depression.
link |
So if you're getting the impression
link |
that the endogenous cannabinoids
link |
are working in a number of different ways
link |
and it's not very straightforward, you're right.
link |
In fact, that's the message that I'd like you to take away.
link |
The endogenous cannabinoids
link |
are sometimes increasing neuronal communication.
link |
This can lead to increases in mood
link |
or increases in the likelihood
link |
that someone will talk a certain way
link |
or behave a certain way or feel a certain way.
link |
They can also lead to decreases in synaptic transmission,
link |
that is communication between neurons,
link |
in ways that will make somebody's mood lower
link |
or will make them less hungry or more hungry.
link |
And here's the really key thing.
link |
There are two kinds of endogenous cannabinoid receptors
link |
referred to as CB1 and CB2.
link |
And we can say with confidence
link |
that CB1 is highly enriched in the nervous system
link |
and especially within the brain.
link |
It's found not everywhere,
link |
but almost everywhere in the brain
link |
and elsewhere in the nervous system,
link |
so spinal cord and other aspects of the nervous system.
link |
CB2, the cannabinoid receptor.
link |
CB2 is largely located in the tissues of the body,
link |
including the immune system, the liver,
link |
even the genitals, et cetera.
link |
So what this means is that the endogenous cannabinoids
link |
are having these sorts of effects on neurons
link |
that I talked about,
link |
but they are also having effects on immune cells,
link |
on reproductive organs, on liver, on digestion,
link |
on hunger, et cetera,
link |
through mechanisms that are divorced from the function
link |
of the nervous system of neurons.
link |
Now, in reality, no system of the brain and body
link |
is divorced from the nervous system
link |
because the nervous system is controlling everything.
link |
There is really the master controller
link |
and everything's feeding back to the nervous system,
link |
so it's a two-way street.
link |
But the simple way to think about it is CB1 receptors
link |
are mainly in the nervous system
link |
and CB2 receptors are mainly in the body
link |
and endogenous cannabinoids.
link |
Again, EAE, anatomide, and 2AG, arachidinol glycerol,
link |
are impacting CB1 and CB2 receptors.
link |
Today, we're mainly going to talk about CB1 receptors
link |
because they are the ones that are responsible
link |
for most of the familiar effects of cannabis.
link |
But the key takeaway at this point
link |
is to really understand that the major effects
link |
of your endogenous cannabinoids on these receptors
link |
in this particular CB1 are very nuanced.
link |
It depends on context, it depends on which neurons.
link |
It's sometimes increasing communication between neurons,
link |
sometimes decreasing it.
link |
And then along comes cannabis.
link |
And that cannabis, again, can arrive by smoking,
link |
by vaping, by edible.
link |
And cannabis contains THC and CBD
link |
that potently bind the CB1 receptor.
link |
And now the effects of the CB1 receptor
link |
being occupied by THC or being occupied by CBD
link |
are not very nuanced.
link |
In fact, they are very predictable.
link |
And especially important is to understand
link |
that they are so strong and they park in that receptor
link |
with such affinity, with such force and precision
link |
and stubbornness and refusal to leave that receptor
link |
that they completely out-compete
link |
the endogenous cannabinoid system.
link |
In fact, they leave the endogenous cannabinoid system
link |
essentially dysfunctional,
link |
which in some cases may be a good thing,
link |
but in most cases is going to lead to problems
link |
And we'll talk about what sorts of problems.
link |
And again, I feel obligated to say,
link |
this is not me saying don't ingest cannabis or THC or CBD.
link |
That's not what I'm saying.
link |
What I'm saying is if you evaluate the potency,
link |
that is in technical terms,
link |
it would be the affinity with which these compounds,
link |
THC and CBD and CBN bind to these endogenous receptors.
link |
That would be like a howitzer gun,
link |
like a cannon going off as compared to endogenous cannabinoid
link |
whether or not it's EAE or 2AG,
link |
which is more like a cap gun level of activation,
link |
at least in this analogy.
link |
So now you have what at least I would like to think
link |
is a fairly complete understanding
link |
of the different varieties of cannabis,
link |
at least at a broad sweep
link |
and the different biological effects that they can have,
link |
at least in terms of the major receptors
link |
and in retrograde signaling, et cetera, et cetera.
link |
Now let's take a step back into the real world
link |
and evaluate or think about
link |
what happens when somebody smokes cannabis
link |
or ingest cannabis by way of edible
link |
or tincture or something of that sort.
link |
Cannabis is very fast to enter the bloodstream.
link |
In fact, within 30 seconds,
link |
it's going to enter the brain
link |
and permeate throughout the brain and body.
link |
That's very, very fast.
link |
I mean, we contrast that with something like alcohol
link |
or even nicotine, depending on how the nicotine
link |
is delivered, that is a very fast delivery
link |
of the psychoactive and biologically active compound,
link |
which in this case is THC and CBD
link |
and probably some other things as well.
link |
So within 30 seconds,
link |
it reaches the brain and bodily tissues.
link |
And within 30 to 60 minutes,
link |
it's going to reach its peak concentrations
link |
and have its peak biological effects.
link |
Those aren't always the same thing,
link |
but in the case of cannabis,
link |
and again, here I'm using cannabis
link |
as a kind of an umbrella term for THC and CBD,
link |
the effects are going to peak at about 30 to 60 minutes
link |
after bringing those compounds into the body
link |
in some way or another.
link |
And the effects tend to last
link |
anywhere from three to four hours,
link |
although there's some variation on that
link |
depending on individual metabolism,
link |
whether or not somebody is familiar with the compound,
link |
believe it or not, psychologically familiar,
link |
but also biologically familiar,
link |
or whether or not it's a first time use
link |
or occasional use and so on.
link |
THC and CBD and other components of cannabis
link |
are highly what we call lipophilic.
link |
That is they have an affinity toward
link |
and they can actually pass through fatty tissues.
link |
Now, every cell in your body,
link |
but especially neurons have a double layer of fat
link |
And of course, when people hear fat,
link |
they always think, ooh, fat's bad, fat's whatever.
link |
Most of the world seems to want to lose fat or bodily fat.
link |
Here we're talking about the fatty membrane,
link |
the barrier around each tissue.
link |
In this case, we're talking particularly about neurons.
link |
And THC and CBD and the other components of cannabis
link |
are highly lipophilic.
link |
So they can get into essentially all cells
link |
just simply by flowing into them.
link |
They will also remain in those cells for a long time.
link |
So I know that a number of people,
link |
depending on whether or not they get tested for work
link |
or for sport or otherwise for cannabis or CBD and THC,
link |
don't take this as a strict number,
link |
but typically if one ingests CBD or THC,
link |
smokes cannabis, ingests orally, et cetera,
link |
it doesn't matter.
link |
It's going to stay in that fatty tissue
link |
and can be detected for at least as long as 80 days
link |
And there's a whole industry as to, you know,
link |
how to accelerate the clearance.
link |
And I should just tell you that just losing bodily fat
link |
isn't going to eliminate it from your system,
link |
maybe partially in those fat cells,
link |
but certainly intravisceral fat and other fatty tissue
link |
that's in and around the brain and body
link |
is going to harbor that THC molecule and the CBD molecule
link |
for quite a long while, at least 80 days.
link |
Okay, so if someone smokes cannabis
link |
or they ingest cannabis,
link |
very rapidly gets into the bloodstream
link |
and the components that are psychoactive
link |
get into the bloodstream
link |
and are immediately able to access neurons and other cells
link |
and start having these effects of parking
link |
with those endogenous cannabinoid receptors
link |
and impacting the signaling between neurons,
link |
which leads to the subjective effects of cannabis,
link |
including THC and CBD.
link |
So let's talk about what those different
link |
subjective effects are.
link |
Again, this is going to vary depending on whether or not
link |
people are ingesting sativa varieties of cannabis.
link |
Just to remind you, those tend to be elevated.
link |
Mood, alertness, talkativeness,
link |
people who take sativa varieties tend to talk a lot more
link |
than they would otherwise.
link |
Again, there are exceptions to this.
link |
Of course, there are exceptions.
link |
I'm sure there are people out there shouting,
link |
although I guess if you're the quiet people
link |
who don't talk too much, you're probably not shouting,
link |
or if you're not, you're not doing sativa.
link |
But in any event, there are exceptions,
link |
but there are also general rules.
link |
And the sativas tend to meet people
link |
sort of mood elevated, energetic,
link |
again, the sort of head high.
link |
And indica varieties tend to do the opposite,
link |
more of a sedative, relaxant, et cetera.
link |
Why and how would they do that?
link |
Okay, without going into an extensive deep dive
link |
into the different neurotransmitter systems
link |
of the brain and body,
link |
what we know for sure is that CB1 receptors
link |
are present on an enormous number of different neurons
link |
in brain structures and neural circuits,
link |
so that the sativa varieties that act as sort of a stimulant
link |
making people feel happy,
link |
because in general, they do tend to elevate mood,
link |
at least at certain dosages.
link |
Talkative tend to make people feel
link |
like they have ideas that are interesting,
link |
that they might want to share,
link |
tend to narrow their context,
link |
so we tend to increase focus.
link |
This is something that's not often discussed about cannabis,
link |
but it can, especially the sativa varieties
link |
can increase people's level of focus to particular things,
link |
something they're watching or something they're doing,
link |
or music allows them to narrow their sense of focus.
link |
That's going to occur by activation of CB1 receptors
link |
in the so-called prefrontal cortex,
link |
which is just behind the forehead.
link |
And the prefrontal cortex acts as a strong modulator
link |
of so-called limbic circuitry and other circuitry
link |
that is more stress-oriented.
link |
The way to think about the stress and limbic circuitry,
link |
such as the amygdala, which many people have heard about,
link |
is that they aren't really circuits for fear and stress.
link |
They are circuits that are constantly evaluating
link |
one's own internal state, heart rate, et cetera,
link |
and what's happening externally.
link |
And sorry to say, but the default of those systems
link |
is to detect danger, the sort of threat detection systems.
link |
And then the prefrontal cortex largely acts
link |
as a brake on those systems,
link |
sort of like the reins pulling back on a steed of horses
link |
that would otherwise just kind of take off.
link |
And so the sativa varieties tend to increase CB1 activation
link |
in the prefrontal cortex and in other circuitry
link |
that then leads to a kind of overall reduction in stress
link |
because of the way that prefrontal circuitry
link |
can reduce activation of the amygdala.
link |
Now that, of course, does not explain
link |
why some people become very stressed and very paranoid
link |
when they smoke sativa varieties
link |
or other varieties of cannabis
link |
or ingest other varieties of cannabis.
link |
We will talk about the paranoid effect and why that occurs
link |
and who might predict that would occur to them in it
link |
But I just want to give you a sense of how this is working
link |
because as I mentioned before,
link |
THC and or CBD are going to bind that CB1 receptor,
link |
let's say in prefrontal cortex
link |
and neurons of prefrontal cortex is going to bind there.
link |
And then there'll be a retrograde signaling
link |
back to the presynaptic neuron.
link |
And in the case of prefrontal cortex,
link |
what's happening is it's increasing transmission,
link |
increasing the release of neurotransmitter
link |
in prefrontal cortex.
link |
However, at the same time,
link |
the very same THC and CBD that was brought into the system
link |
is binding the very same type of receptors,
link |
CB1 receptors in other brain structures,
link |
such as the amygdala
link |
and causing retrograde signaling
link |
back to the presynaptic neurons in the amygdala,
link |
but it's quieting the activation of those neurons.
link |
So this is interesting, right?
link |
We have the same compounds, THC and or CBD
link |
brought into the body and brain binding the same receptors,
link |
in this case, the CB1 receptors,
link |
but depending on where those receptors are located
link |
and which brain areas we're referring to,
link |
they are either causing heightened levels of alertness
link |
and activation of systems that are designed
link |
to make you talkative and alertness and mood, et cetera,
link |
focus, or they are causing suppression of those circuitries.
link |
So we have kind of a seesaw effect here
link |
where the same compound is increasing mood and alertness
link |
and focus in the prefrontal cortex
link |
and is decreasing stress and threat detection
link |
And that's one of the reasons why,
link |
especially the sativa varieties of cannabis,
link |
allow people to enter these states of focus,
link |
some might even say flow,
link |
although I don't want to go into what flow states
link |
really are, that's for a different discussion,
link |
and it's very poorly defined as it is.
link |
And I certainly don't want to give people the impression
link |
that cannabis increases flow states,
link |
because that's not always the case,
link |
and certainly most often is not going to be the case.
link |
But the idea here is that this molecule
link |
comes into our brain and is shifting everything
link |
towards a state of focus, elevated mood,
link |
of heightened sense of importance
link |
about whatever it is that we happen to be doing.
link |
And now of course, whatever we could happen to be doing
link |
could be writing a song, writing poetry,
link |
communicating with somebody,
link |
but it could also be something as trivial
link |
as watching cartoons or watching a movie,
link |
which is not trivial in its own right,
link |
but in terms of thinking about the creative aspects
link |
or the creativity stimulating aspects of cannabis,
link |
not sort of productivity oriented.
link |
So narrowed focus, elevated mood,
link |
more relaxed and yet energetic.
link |
That's the major effects of the sativa varieties,
link |
except, and this is a really big, bold face,
link |
triple underlined except, except in some individuals,
link |
depending on dosage,
link |
but also depending on preexisting neural circuitry
link |
and propensity for anxiety,
link |
some people ingest or smoke sativa varieties,
link |
and regardless of whether or not it's a type one,
link |
type two or type three variety, okay,
link |
regardless of the ratio between THC and CBD,
link |
people will experience intense anxiety and paranoia.
link |
Now, how do you predict
link |
who will experience intense anxiety and paranoia
link |
and who will experience intense relaxation,
link |
focus and sense of creativity from ingesting or smoking
link |
a type one, type two or type three sativa?
link |
Well, there is no way to predict that.
link |
And there's a lot of kind of what I would call street lore
link |
or dorm room lore or kind of peer, not peer reviewed,
link |
but sort of peer discussed,
link |
I mean, among friends and people in acquaintances,
link |
lore out there that what one needs to do
link |
is simply smoke more, right?
link |
Or just ingest more, you hear that.
link |
Oh, well, listen, if it makes you paranoid,
link |
you simply need to use more.
link |
That is absolutely categorically false.
link |
Everything we know about the way that THC and CBD work
link |
is that they tend to potentiate,
link |
that is increase the effects of these different systems
link |
at given synapses and in different areas
link |
of the brain and body.
link |
That is if someone experiences paranoia or anxiety
link |
from a given strain of the marijuana plant
link |
or from ingesting an edible in a particular way
link |
or a particular kind of edible,
link |
that person is very likely to experience the same effect
link |
every time they ingest that strain or variety.
link |
This is part of what's led to this enormous industry.
link |
I mean, there are a number of different reasons,
link |
but this is part of what's led to this enormous industry
link |
of highly customized cannabis,
link |
where people will spend some time
link |
really seeking out the different strains of cannabis
link |
and hybrids of cannabis that work best for them
link |
and work best for them in particular context.
link |
I wish I could tell you that if you are a person
link |
who is between five foot seven and six feet tall
link |
and you have blue eyes or brown eyes,
link |
that the sativa varieties are going to be right for you
link |
or that the sativa varieties
link |
are going to give you panic attacks.
link |
The only way to determine it would be
link |
to actually experience ingesting those or smoking those,
link |
which is certainly also not what I'm suggesting, right?
link |
I'm not telling you what to do or what not to do,
link |
but there are no good predictors.
link |
In fact, if you look in the literature,
link |
it is not at all clear that people
link |
who have a heightened level of anxiety
link |
when they do not smoke cannabis
link |
will experience cannabis as less paranoia inducing
link |
That's simply not the case.
link |
Now, what we can say for sure
link |
is that general categories of effects,
link |
such as increased focus and reduced anxiety
link |
are largely due to activation of areas
link |
like the prefrontal cortex.
link |
Now, unlike other compounds like nicotine or alcohol
link |
or neurotransmitter systems like dopamine,
link |
when we talk about the cannabinoid system
link |
and I say effects, biological effects, psychoactive effects,
link |
I want you to keep in mind always, please, please, please,
link |
keep in mind that those effects can be varied
link |
and often opposite in direction.
link |
So let's just give an example of that.
link |
I just mentioned that when people smoke or eat sativa,
link |
that it tends to lead to one specific set of,
link |
or generally leads to one specific set of effects,
link |
heightened focus, mood, et cetera.
link |
Whereas when they ingest or smoke indica
link |
and its components, right?
link |
Again, we're still talking about THC and CBD
link |
in varying ratios, but now indica cannabis
link |
and say, well, why would it improve
link |
the transition time to sleep?
link |
Or at least give people the impression
link |
that it improved the transition time to sleep.
link |
We'll talk about what indica actually does for sleep
link |
But indica also tends to suppress activation
link |
of the amygdala and threat detection centers in the brain.
link |
Again, binding the same CB1 receptors
link |
and those retrograde signaling mechanisms
link |
that talked about before.
link |
But it also tends to shut down the hippocampus,
link |
an area of the brain associated with memory,
link |
which is why indica varieties lead to pronounced,
link |
or I should say profound defects in short-term memory
link |
and sometimes in long-term memory as well
link |
if it's consumed over long periods of time.
link |
We'll talk about short, medium and long-term consumption,
link |
occasional consumption going forward.
link |
So what I'd like you to take away
link |
from this component of the discussion is,
link |
first of all, the mechanism of action
link |
by which cannabis impacts the brain and body,
link |
but in particular, the brain is going to be
link |
through CB1 receptors and those CB1 receptors
link |
can lead to either an acceleration or a break
link |
on particular biological mechanisms.
link |
And there are going to be a constellation
link |
of different accelerations and breaking
link |
of different neural systems in the brain and body,
link |
depending on whether or not people ingest sativa
link |
or indica or some hybrid strain.
link |
And perhaps most importantly,
link |
even if you didn't understand anything that I've said
link |
about the biology of these different strains
link |
and the receptors, please do understand
link |
that there is no way to predict what the effect
link |
of a given strain will be on an individual.
link |
There has been extensive exploration
link |
as to whether or not people who are so-called mellower
link |
or more anxious or any number
link |
of different personality dimensions will respond
link |
in one way or the other.
link |
But in fact, there is no way to tell.
link |
Layer on top of that, the fact that dosing THC and CBD
link |
can be fairly straightforward in the form of edibles, right?
link |
Because there can be, at least if it's a controlled source,
link |
a defined number of milligrams of THC,
link |
a defined number of milligrams of CBD,
link |
that's true for ingestibles.
link |
It's much harder to gauge that
link |
from the smokable forms of cannabis,
link |
especially if those smokable forms of cannabis are obtained
link |
through sources where there isn't a lot of clear information
link |
about the total amount of THC in that product.
link |
Now, this is all changing quite a lot nowadays
link |
because of the commercialization of THC and CBD products
link |
and cannabis in a number of different areas,
link |
including in the United States.
link |
But still many people are ingesting cannabis, THC, CBD
link |
through sources where they don't really know
link |
how much they're bringing into their system.
link |
And so whether or not someone gets
link |
incredible anxiety relief, enhanced sense of mood
link |
and focus and wellbeing, pain relief, et cetera,
link |
or whether or not they have full-blown panic attacks,
link |
et cetera, is very hard to predict
link |
based on dosage information alone.
link |
Now, of course, we can create broad categories
link |
and we were going to talk about studies
link |
that create broad categories of low dose,
link |
moderate dose and high dose, frequent use and infrequent use
link |
but unlike alcohol, unlike nicotine,
link |
we can't really point to specificity
link |
of X amount of alcohol, grams of alcohol per week,
link |
which is safe or X amount of alcohol, which is not safe.
link |
And so I know a lot of people out there are wondering,
link |
how often can they smoke cannabis
link |
or how often can they eat cannabis or THC or CBD
link |
in any number of its different forms and products safely?
link |
Well, we have to really define what safely means
link |
and we have to really acknowledge
link |
that there's a pretty loose set of controls
link |
over what one is bringing into their brain and body
link |
as they ingest THC and CBD.
link |
But even under conditions in which it's very controlled,
link |
it's very hard to predict what those effects will be.
link |
So before moving into specifics of taking cannabis
link |
or not taking cannabis, who should, who shouldn't,
link |
what the medicinal purposes are
link |
and what some of the newer exciting data point to,
link |
I just briefly want to make a list
link |
and I promise very briefly, I know I'm not often concise
link |
but I do try to be thorough for your sake.
link |
I want to make a very brief list of the different brain areas
link |
that are impacted by THC and CBD
link |
and why THC and CBD have the various effects they do.
link |
When somebody smokes or ingests cannabis,
link |
doesn't matter what the THC or CBD ratio is,
link |
if they experience deficits in memory
link |
and that's almost always present,
link |
that's going to be because of reductions
link |
in electrical activity within this brain region
link |
we call the hippocampus, okay?
link |
Hippocampus means seahorse, it's shaped like a seahorse,
link |
anatomists like to name things after what things look like
link |
but hippocampus memory, memory is reduced
link |
in particular short-term memory.
link |
That's true regardless of whether or not
link |
one is using sativa, indica or some hybrid.
link |
In general, the prefrontal cortex is going to be activated
link |
by the sativa varieties, which is going to increase thinking
link |
and narrowly constrain focus to some activity
link |
and that's more commonly associated
link |
with the sativa varieties.
link |
The indica varieties, as I mentioned before,
link |
tend to lead to a suppression of activity
link |
in prefrontal cortex, believe it or not,
link |
and turn off thinking and planning.
link |
This is why indica varieties are often used for relaxation
link |
and for promoting sleep.
link |
Regardless of whether or not sativa or indica variety,
link |
and again, regardless of the ratio of THC to CBD,
link |
there is a general suppression of neural circuits
link |
within the so-called basal ganglia and cerebellum.
link |
Basal ganglia and cerebellum are areas of the brain
link |
that are involved in action planning and withholding action,
link |
so that would be the basal ganglia,
link |
so-called go-no-go circuitry,
link |
and the cerebellum, which is involved in balance
link |
but also motor planning and motor sequencing.
link |
This is why people who smoke marijuana,
link |
regardless of the strain,
link |
will tend to be less physically mobile.
link |
Other common effects are reddening of the eyes,
link |
dryness of the mouth,
link |
that's actually caused by the same general mechanism,
link |
which is a reduction in the secretion of saliva
link |
and of sort of tears and lubrication of the eyes
link |
from the lacrimal glands of the eyes
link |
because of the presence of largely CB2,
link |
but also CB1 receptors in the mouth and on the eyes.
link |
And there tends to be,
link |
especially with certain strains of cannabis,
link |
increase in appetite, so-called munchies,
link |
and that has everything to do with very, very high density
link |
of CB1 receptors in the hypothalamus,
link |
and in particular areas of the hypothalamus,
link |
like the arcuate nucleus of the hypothalamus,
link |
other areas as well, of course,
link |
that have tons of CB1 receptors, bind THC and CBD,
link |
and activate the neurons that strongly stimulate appetite
link |
through two mechanisms.
link |
One is a cognitive mechanism of creating a preoccupation
link |
with food and anticipation of taste,
link |
as well as the experience of taste,
link |
so the narrowing of focus to what you want to go eat, right?
link |
You really crave, I don't know, pizza,
link |
it seems to be high fat, high carbohydrate foods,
link |
but really crave pizza and narrowing of focus
link |
so that you're not thinking about anything else,
link |
but also signaling from the hypothalamus to the gut
link |
to neurons within the stomach itself
link |
that regulate blood sugar.
link |
So there are strong effects on blood sugar of THC and CBD
link |
that generally lead to increases in appetite.
link |
So two parallel mechanisms, one within the brain,
link |
one within the body, increasing appetite.
link |
So there's an array of different effects.
link |
And as I mentioned before,
link |
CB1 receptors are present all over the nervous system
link |
in the brain, the spinal cord.
link |
In fact, the presence of CB1 receptors in the spinal cord
link |
largely explains the fact that THC and CBD,
link |
to some extent, although it's not very well studied,
link |
can provide some pain relief.
link |
I say some because a lot of people perceive
link |
or believe that they experience more pain relief
link |
from cannabis than they actually do.
link |
It actually has a lot to do with a perceptual shift
link |
to basically focusing on other things,
link |
but there does seem to be some anti-nociceptive,
link |
meaning anti-pain effects of cannabis, THC in particular,
link |
and that is exerted largely through effects
link |
on CB1 receptors in neurons of the spinal cord.
link |
So a broad array of effects are taking place
link |
regardless of what strain you take
link |
and whether or not you eat the cannabis
link |
or you smoke the cannabis.
link |
And the broad array of effects can be explained by the fact
link |
that that retrograde signaling can lead to activation
link |
or suppression of activity in various neurons.
link |
So now I'd like to take a step back
link |
from the biology of cannabis and THC and CBD
link |
and all the signaling and receptors, et cetera,
link |
and really just focus on cannabis use.
link |
And wherever possible,
link |
I will point to the specific strains that have been studied
link |
and the ratios of THC to CBD.
link |
But I have to say that unfortunately,
link |
most studies of marijuana of cannabis,
link |
while they have been very careful
link |
to detail the amount of THC,
link |
low dose, medium dose, or high dose,
link |
and actually getting very specific,
link |
right down to the number of milligrams
link |
or even how much circulating THC is present
link |
after somebody smokes a joint or ingests cannabis,
link |
most studies have not distinguished
link |
between sativa and indica strains.
link |
And that's unfortunate because in the real world,
link |
people are distinguishing between sativa and indica strains
link |
in their patterns of use and what they prefer
link |
and what they don't prefer,
link |
even what they prefer to smoke during the day
link |
or ingest during the day versus night.
link |
Believe it or not, there are people
link |
who are using certain strains during the day
link |
and other strains at night.
link |
But the science is yet to catch up to that.
link |
Or I should say more accurately,
link |
the general public and the themes that are emerging
link |
and the practices that are emerging around cannabis,
link |
especially in states where it's decriminalized or legalized,
link |
are occurring at such a rapid rate
link |
that there's absolutely no way
link |
that the science could keep up.
link |
This is a naturally occurring experiment.
link |
Not to say that it's natural, like people should do it,
link |
but it's an experiment that's happening in real time
link |
in the real world,
link |
much faster than controlled studies
link |
within university laboratories
link |
and other laboratories can keep up.
link |
So at this point, I think it's appropriate to ask ourselves,
link |
why do people even use cannabis?
link |
I mean, what are they trying to achieve?
link |
Is it always about not feeling pain?
link |
Is it always about reducing anxiety?
link |
Well, sometimes it is,
link |
but oftentimes people are using cannabis
link |
in order to achieve a particular state.
link |
And we could use a broad brush and say,
link |
well, they just like being high,
link |
but while that may be true in a lot of circumstances,
link |
and I have to believe it actually is true
link |
in a lot of circumstances,
link |
there are a lot of people who use cannabis
link |
in a very directed way,
link |
or they get quote unquote high in order to achieve states
link |
that to them are particularly attractive.
link |
And one such state is a state of creativity.
link |
And this brings us to a broader theme,
link |
which is does cannabis increase creativity?
link |
And if so, is it the THC, the CBD?
link |
What's the appropriate ratio
link |
or the best ratio for accessing creativity?
link |
This is an interesting and important discussion, I believe,
link |
because creativity is one of the more sought after
link |
and more elusive states that humans can experience.
link |
And yet, if you look at human evolution,
link |
you look at our progression
link |
in terms of technology development and culture
link |
and music and poetry, et cetera,
link |
we really can look to creativity as the state
link |
that fostered so much of that evolution.
link |
So whether or not you're into technology
link |
or you're into art or music,
link |
whether or not you're just somebody
link |
who wants to expand their understanding
link |
or their experience of life in some way,
link |
creativity is a fundamentally important state
link |
to try and access and to try and access regularly
link |
and to try and tap into
link |
in order to eventually produce something,
link |
in order to create something of meaning that exists,
link |
not just in that creative state,
link |
but to yourself after that creative state has gone away.
link |
So the painting that you paint in the creative state
link |
hopefully is a painting that still inspires
link |
and has impact after you exit that creative state
link |
and that will inspire others.
link |
And this could be true for any number of different things,
link |
not just painting.
link |
So does cannabis increase creativity?
link |
The short answer is it depends.
link |
First of all, we need to define creativity.
link |
Here we are as thinking as scientists,
link |
if not already scientists.
link |
And there are basically two modes of thinking
link |
that are associated with creativity
link |
and they don't completely explain creativity.
link |
But if you look in the research, the psychology research
link |
and the neuroscience research,
link |
you'll hear about convergent thinking
link |
and divergent thinking.
link |
Convergent thinking is taking loose ideas
link |
and kind of braiding them together,
link |
finding a common thread,
link |
synthesizing and organizing those different ideas
link |
into some common or specific framework
link |
in order to get or create some specific outcome.
link |
So convergent thinking is basically the person in the room
link |
who's listening to all the ideas and taking them all in.
link |
Maybe it's a panel of how should we get a certain product
link |
out to market or what are the different motifs
link |
that we should include in a piece of music?
link |
Or what should we do in terms of re-architecting
link |
a given physical space,
link |
taking in those different opinions,
link |
those different ideas from different people,
link |
and then synthesizing them and coming up with one
link |
or a small subset of coherent ideas that incorporate
link |
some or all of the ones that they heard.
link |
Okay, so that's convergent thinking.
link |
It doesn't have to involve a panel of people talking to you.
link |
I use that as an example of what goes on
link |
inside your own head
link |
when you are engaging in convergent thinking.
link |
You're thinking, well, so-and-so said this,
link |
and I think that, and you're kind of braiding them through
link |
and trying to get some common theme,
link |
some common vector to emerge from that.
link |
Divergent thinking on the other hand
link |
is best described as brainstorming.
link |
It's exploring ideas and continuing to move
link |
into the variation and the vastness of ideas
link |
in hopes of eventually being able to converge
link |
on some novel idea or framework, okay?
link |
So these are similar and related,
link |
but typically the creativity process
link |
involves first brainstorming and divergent thinking,
link |
and then in order to arrive at something
link |
to actually create something, right?
link |
The verb create, not just thinking about
link |
what you might create, which occurs during divergent thinking
link |
but actually creating something, a specific painting,
link |
a specific song, a specific body of literature,
link |
a specific scientific project or experiment, and so on.
link |
That usually involves convergent thinking.
link |
Now, these can be explored in the laboratory
link |
and they can be explored in the laboratories
link |
through sets of different types of questionnaires
link |
or even tasks that you can give human subjects,
link |
and this has been done extensively.
link |
And across the entire body of data,
link |
and by that, I mean literally hundreds of studies
link |
that have explored the relationship
link |
between particular neural circuits and neurochemicals,
link |
convergent and divergent thinking,
link |
we can arrive at a principle.
link |
And the principle involves a molecule
link |
that many of you have heard about before,
link |
which is dopamine.
link |
Dopamine is a neuromodulator, it's involved in motivation,
link |
and it tends to direct our attention to things outside of us
link |
but it's also closely related to convergent thinking
link |
and divergent thinking and to the creative process.
link |
And therefore, it should come as no surprise
link |
that diseases of the nervous system, excuse me,
link |
such as bipolar disorder,
link |
which we've done an episode all about bipolar disorder,
link |
or schizophrenia, or mood disorders
link |
that impact the levels of dopamine,
link |
either make it way, way too high or way, way too low,
link |
strongly impact whether or not people will be creative.
link |
And I think the short takeaway
link |
that makes the most sense in terms of framing this,
link |
and we cover this on the episode on bipolar disorder,
link |
sometimes called bipolar depression,
link |
is that in professions
link |
where there's a lot of creativity required
link |
in order to succeed, so again,
link |
musicians, composers, artists, et cetera,
link |
you tend to find more manic depression
link |
and manic depression, at least in the manic states,
link |
the hyperactive states are correlated
link |
with elevated levels of dopamine.
link |
Likewise, it has been seen over and over throughout history
link |
that individuals that have mild forms of schizophrenia
link |
or even full-blown schizophrenia,
link |
many famous painters, for instance, or musicians,
link |
they are known to have elevated levels of dopamine
link |
and they are quite creative.
link |
Now, that doesn't mean everybody who's creative
link |
has elevated levels of dopamine,
link |
although it's likely that their levels of dopamine
link |
are at least not diminished.
link |
And it doesn't mean that non-creative people
link |
have low levels of dopamine,
link |
so don't get carried away with the interpretation here.
link |
But the point is this.
link |
Dopamine levels strongly relate to the probability
link |
that you can engage in convergent and divergent thinking,
link |
and they do so in the following way.
link |
When dopamine levels are high,
link |
divergent thinking is more likely.
link |
That is, when people have a lot of dopamine circulating
link |
they tend to be very expansive with their ideas.
link |
They tend to brainstorm a lot.
link |
They tend to be comfortable and even want to,
link |
or reflexively, throw out a lot of ideas
link |
that sometimes even seem a little disconnected.
link |
Some people might think of this
link |
as kind of attention deficit, but it's not.
link |
It's really the idea of throwing out disparate ideas, right?
link |
You know, you hear sometimes, you know,
link |
you throw things against the wall and see what sticks.
link |
Well, these people, that's obviously an analogy,
link |
but people are throwing lots of things against the wall
link |
and seeing what stick,
link |
and then seeing how the things that stick fit together.
link |
That's divergent thinking,
link |
and elevations in dopamine
link |
tend to increase divergent thinking.
link |
However, they tend to do this
link |
in kind of an inverted U-shape way.
link |
For those of you that are watching on YouTube,
link |
I'm just drawing kind of a hump, obviously,
link |
and for those of you listening, just imagine a U,
link |
the shape of a letter U, and then just flip it upside down
link |
so it looks like a bump.
link |
Turns out that when dopamine levels are very low,
link |
there's a low probability of divergent thinking.
link |
When dopamine levels are high, as I mentioned before,
link |
there's a high level or probability of divergent thinking.
link |
But when dopamine levels go very, very high,
link |
then there's, again, a reduction in divergent thinking.
link |
In other words, there's a kind of a sweet spot
link |
of elevated dopamine for divergent thinking.
link |
And again, divergent thinking
link |
is critical for the creativity process
link |
because creativity, by definition,
link |
is taking a novel set of ideas
link |
and arranging them in a particular way,
link |
or taking existing ideas and arranging them in a novel way
link |
that then you eventually converge on some new product,
link |
new idea, new song, et cetera.
link |
Now, convergent thinking follows a very different pattern.
link |
When dopamine levels are high,
link |
convergent thinking is not very likely.
link |
And when dopamine levels are low,
link |
convergent thinking is very likely.
link |
So here, using arguably a very reductionist view,
link |
we're looking at all of this thing of,
link |
we're calling creativity
link |
through a very neurosciency reductionist lens,
link |
The creative process involves going into a state
link |
where you're willing to consider a lot of options,
link |
many of which seem distantly
link |
or not even connected to one another.
link |
And dopamine facilitates that divergent thinking state
link |
in which you are perfectly happy
link |
and in fact experience a kind of a joy or elation,
link |
a comfort and a pleasure
link |
in organizing all these different ideas
link |
that to anyone else might seem not that related.
link |
But when your dopamine levels are elevated,
link |
these all seem like great ideas
link |
and that maybe there are connections there, right?
link |
You're not accepting all of them as true and valid
link |
and interesting and combining them,
link |
but there's this idea that it's worth entertaining
link |
the possibility, at least for moments.
link |
And then as dopamine levels drop,
link |
there is the process of convergent thinking,
link |
which is taking options down off the wall,
link |
saying, no, no, that doesn't fit with that,
link |
doesn't fit with that,
link |
but ah, that fits with that and that can work.
link |
That feels right or sounds right or looks right.
link |
That's the creativity process.
link |
And so I think this is not just important
link |
for understanding cannabis,
link |
which we'll get back to in a moment,
link |
but it's important for understanding creativity
link |
and brain states in general.
link |
Brain states are not, as we would say,
link |
a square wave function.
link |
You don't just drop into a trench of creativity.
link |
Creativity is not an event, it's a process.
link |
And what I'm telling you is that it's a process
link |
that involves divergent thinking and consideration,
link |
a lot of different ideas.
link |
That's correlated with high, but not too high dopamine.
link |
And then one has to transition into a state
link |
of convergent thinking,
link |
which is really homing in on the ideas
link |
that seem to have validity or that could have validity
link |
and getting rid of everything else.
link |
And that's associated with low dopamine.
link |
It's more about logical implementation and consideration
link |
as opposed to thinking about and considering everything.
link |
So let's now return to the question of whether or not
link |
cannabis and its different components increase creativity.
link |
And when you look at the literature on this,
link |
you find studies that very clearly point to a yes,
link |
it increases creativity.
link |
And it's not surprising therefore
link |
that cannabis can increase dopamine transmission,
link |
that is dopamine levels, in certain brain areas,
link |
in particular brain areas involved in thinking and planning.
link |
Okay, so cannabis increases dopamine in these areas,
link |
elevated dopamine increases divergent thinking,
link |
and divergent thinking is associated with creativity.
link |
And there are studies that support the idea
link |
that cannabis can increase creativity.
link |
However, there are at least as many studies
link |
that say that cannabis does not increase creativity,
link |
that cannabis increases consideration of multiple ideas,
link |
perhaps through elevation of dopamine and related systems,
link |
but that ultimately the ideas that converge from that
link |
are not truly creative ideas.
link |
At least they don't make the criteria
link |
for creative brainstorming and extraction of ideas
link |
that are truly novel.
link |
So it doesn't increase creativity.
link |
So which one is it?
link |
Well, fortunately, there's an entirely distinct set
link |
of literature that has taken all the other literature
link |
into consideration, and here's where we arrive.
link |
So there's a really nice study
link |
that explored creativity in cannabis users,
link |
and we will provide a link to the study.
link |
First author is Emily LaFrance,
link |
and the title of the paper is somewhat amusing
link |
in its own right, which is, it starts with a question.
link |
Inspired by Mary Jane, of course,
link |
Mary Jane being one of the kind of old school versions
link |
or ways of talking about cannabis or marijuana.
link |
Nowadays, people refer to it mainly as pot,
link |
has other names too, of course.
link |
And the title of the paper is Inspired by Mary Jane,
link |
Mechanisms Underlying Enhanced Creativity in Cannabis Users.
link |
And I really like this study for a couple of reasons.
link |
First of all, they looked at people who did not use cannabis
link |
as well as people who use cannabis.
link |
So they had two different groups,
link |
but they did not evaluate creativity of the cannabis users
link |
while they were under the influence of cannabis.
link |
They looked at the level of creativity
link |
in these cannabis users
link |
when they were not under the influence of cannabis
link |
and asked whether or not their ability to be creative
link |
was enhanced by cannabis.
link |
Now we're going to compare this to studies
link |
in which people come into the laboratory
link |
and actually use cannabis,
link |
and then they evaluate creativity under that context.
link |
But this study has some unique takeaways
link |
that I think are really interesting.
link |
First of all, they did, yes,
link |
see evidence for enhanced creativity.
link |
And when I say enhanced creativity,
link |
I mean within the context of this divergent thinking thing
link |
that I talked about a moment ago.
link |
And when I say enhanced,
link |
I mean significantly greater than in non-users,
link |
so people that don't use cannabis.
link |
So right now I can imagine that all the cannabis users
link |
are cheering, yes, cannabis increases creativity,
link |
makes people more creative than they would be otherwise.
link |
Well, this is interesting.
link |
We have to ask ourselves how that was accomplished.
link |
And it turns out that one of the major ways
link |
in which it was accomplished is that cannabis users,
link |
even if they are not under the influence of cannabis,
link |
are far more open to novel ideas,
link |
and they have a more explorative and sort of reduced anxiety
link |
or I should say lower anxiety mode of thinking
link |
when they explore novel ideas,
link |
which is essential for divergent thinking.
link |
So they observe both enhanced divergent and convergent
link |
creative type thinking in cannabis users.
link |
And the source of that, they conclude,
link |
is, and here I'll just quote,
link |
"'Cannabis users' higher levels of openness to experience
link |
are responsible for their enhanced self-reported creativity
link |
and convergent thinking test performance.'"
link |
So it's not necessarily that cannabis is increasing
link |
the capacity of the brain areas
link |
that are associated with creativity,
link |
but rather cannabis appears to be increasing in openness
link |
and probably doing that in part through lowering anxiety
link |
in particular people.
link |
And that openness is leading to inclusion of more ideas
link |
during the divergent thinking process, right?
link |
They're willing to consider throwing up more things
link |
on the wall to see if they stick, so to speak.
link |
So in their conclusions, they have a really nice statement.
link |
Again, I'll just read from the paper
link |
because they said it better than I ever could.
link |
Quote, "'While mainstream media has propagated the idea
link |
that cannabis expands the mind and enhances creativity,
link |
our results show the link between cannabis and creativity
link |
is largely a spurious correlation.'"
link |
Meaning that it's not the case
link |
that cannabis increases creativity,
link |
but, and I inserted the but in this quote,
link |
"'But driven by differences in personality
link |
that are related to cannabis use.
link |
For example, openness to experience
link |
that are related to both cannabis use
link |
and augmented creativity.'"
link |
This is a real chicken egg argument.
link |
What do I mean by that?
link |
What I mean is this paper finds
link |
that people who are more open to experience
link |
are more likely to use cannabis
link |
and people who use cannabis
link |
are going to be more open to new experiences.
link |
And that combination of features, openness to experience
link |
and what that openness to new experiences brings
link |
enhances the convergent and divergent thinking
link |
that is characteristic of the creative process.
link |
So in short, cannabis increases creativity,
link |
but through changes in personality
link |
that tap into the creative process
link |
rather than directly impacting the neural circuits
link |
that for instance, turn on creativity.
link |
And I have to say this study is really important
link |
because by exploring cannabis users
link |
not while under the influence of cannabis,
link |
they were able to tap into this very important,
link |
what I believe to be fact.
link |
Because if you think about a study
link |
in which you would have one group using cannabis
link |
and another group not using cannabis
link |
and then you give them some tasks that taps into creativity,
link |
you will see effects and very likely you'll see effects
link |
where cannabis might even increase divergent,
link |
convergent thinking and creativity.
link |
Those results have actually been published
link |
many times before.
link |
But given the varied effects of cannabis and THC
link |
that we talked about earlier
link |
through all that complex signaling stuff,
link |
you can imagine that there will also be other studies
link |
and in fact, there are
link |
where divergent and convergent thinking
link |
and creativity is not assisted by cannabis
link |
and might even be reduced by ingesting cannabis.
link |
However, if one considers that divergent thinking
link |
is absolutely crucial to the creativity process
link |
and the range of things that one will explore
link |
will be enhanced by openness
link |
and by reduced levels of anxiety.
link |
So a willingness to explore different options,
link |
some of which might seem completely crazy
link |
and cannabis increases the personality types
link |
and reduces the anxiety that create that sense of openness.
link |
Well, then it makes perfect sense
link |
why cannabis would increase creativity
link |
in certain individuals, but not directly.
link |
And this study, the one I just referred to,
link |
which I should say was published
link |
in the journal, Consciousness and Cognition,
link |
and again, we'll provide a link to it,
link |
did a wonderful job of teasing out this impact of cannabis
link |
on personality, which then impacts creativity.
link |
So if somebody asks you, or if you're wondering,
link |
or if you feel like cannabis increases creativity,
link |
in some sense, the answer is yes,
link |
but the answer is yes,
link |
because of the ways that it shapes openness to new ideas
link |
and can, I should say can, because not in everybody,
link |
but can in some individuals reduce anxiety.
link |
What this means is that if you are somebody
link |
who experiences anxiety or increased levels of focus
link |
from cannabis, regardless of the strain,
link |
and here I have to imagine people
link |
are exploring different strains
link |
if they're exploring them at all,
link |
exploring different modes of delivery,
link |
smoking or ingestible, et cetera,
link |
if you're somebody who experiences anxiety,
link |
it's very likely that you won't have the increased openness
link |
to experience and divergent ideas
link |
that will facilitate creativity.
link |
However, if you are somebody
link |
who achieves heightened levels of relaxation
link |
and reduced levels of anxiety from cannabis,
link |
regardless of which strain we happen to be talking about,
link |
well then, yes, it will position you
link |
to be in a heightened state of creativity,
link |
at least as defined by convergent and divergent thinking.
link |
One of the more characteristic,
link |
or I should say stereotype qualities
link |
of people that smoke a lot of marijuana
link |
or ingest cannabis through other means
link |
is their changed patterns of speech.
link |
In fact, there's a kind of a lore in the clinical realm
link |
that you can predict or get some strong indication
link |
as to whether or not somebody is a cannabis user
link |
or a pot smoker based on their voice
link |
and their particular tone of voice
link |
and their lack of inflection.
link |
There's a lot of speculation here,
link |
but fortunately it's been studied.
link |
So I'd like to discuss now
link |
whether or not cannabis can impact patterns of speech,
link |
both acutely, meaning while under the influence of cannabis
link |
and over time in chronic cannabis users.
link |
And when I say chronic cannabis use,
link |
I want to be very specific what I mean.
link |
Chronic cannabis use does not necessarily mean
link |
that people are smoking cannabis
link |
or ingesting cannabis every day.
link |
Although certainly if they are,
link |
that qualifies as chronic use.
link |
Chronic use is regular use over time
link |
of anywhere from twice a week or more.
link |
So using cannabis once a month
link |
would not be considered chronic use,
link |
even if it's for many, many years.
link |
Using cannabis or ingesting cannabis in some way or form
link |
twice a week would be considered chronic use.
link |
And then of course,
link |
some of you out there are going to ask me to split hairs
link |
and say, well, what if somebody uses it twice a month?
link |
Well, listen, the clinical literature
link |
and the scientific literature don't get that specific.
link |
And of course there are an infinite number of ways
link |
to arrange one's cannabis use,
link |
everything from zero, none at all,
link |
to constantly every day, all day and everywhere in between.
link |
But think of chronic use as twice a week or more.
link |
Think of occasional use as less than that
link |
and realize that within the realm of chronic use, excuse me,
link |
that or more can be anywhere from twice a week
link |
to every day to just in the evenings, et cetera.
link |
The effects of chronic use of cannabis,
link |
as I just defined it, on speech have been studied
link |
because of this characteristic drawing out
link |
of certain syllables, a slowing of speech,
link |
and in many cases, a total change or alteration
link |
in the way that people speak and use language,
link |
both when under the influence of cannabis
link |
and when not under the influence of cannabis,
link |
if they are chronic users.
link |
And here, we really want to distinguish between THC and CBD
link |
and just make it really simple and say that CBD
link |
is not responsible for most of the psychoactive effects
link |
of cannabis, whereas THC is.
link |
And again, the ratio of CBD to THC
link |
is going to be relevant there,
link |
but let's just think about cannabis and THC
link |
as one in the same for this portion of the discussion,
link |
realizing that, of course,
link |
they are not exactly the same thing.
link |
There's an excellent study entitled,
link |
adults with history of recreational cannabis use
link |
have altered speech production.
link |
And we will provide a link to that.
link |
First author, Adam Vogel, really liked this paper.
link |
It was published in the journal,
link |
Drug and Alcohol Dependence.
link |
We will provide a link to it for you
link |
if you'd like to peruse it in more detail.
link |
The title itself, adults with a history
link |
of recreational cannabis use have altered speech production
link |
tells you pretty much everything you need to know,
link |
except there's some important nuance in here
link |
because as I mentioned earlier,
link |
people who smoke sativa varieties of cannabis
link |
oftentimes will become more talkative, much more talkative.
link |
However, whether or not people tend to rely
link |
on sativa cannabis use or indica cannabis use,
link |
there is a very consistent finding
link |
that people who are chronic users,
link |
again, twice a week or more,
link |
recreational use or medicinal use,
link |
undergo pretty profound changes in the way that they speak,
link |
but in a very specific set of ways.
link |
Now, first of all,
link |
the changes in speech shouldn't surprise us at all
link |
because both sativa varieties of cannabis
link |
and indica varieties of cannabis
link |
impact those brain centers involved in movement,
link |
the basal ganglia, remember the go-no-go circuitry,
link |
the circuitry that makes you want to do things
link |
and the circuitry that makes you want to withhold action,
link |
and it tends to shift the body and brain
link |
toward more inaction.
link |
And cannabis impacts CB1 receptors in the cerebellum,
link |
which is involved in motor planning, execution, and balance.
link |
So regardless of whether or not people are using cannabis
link |
of the sativa or the indica variety,
link |
there are disruptions in motor circuitry.
link |
And as you may have heard,
link |
if you listen to our episode with Rockefeller professor,
link |
Dr. Eric Jarvis, who works on speech and movement,
link |
speech is movement, right?
link |
The movements of the mouth, the movements of the hands,
link |
those are intimately related in terms of our speech.
link |
In fact, the centers of the brain involved in hand movements
link |
are part of the speech areas and vice versa.
link |
Eric actually pointed out
link |
that if you put your hands behind your back,
link |
provided you normally do have use of your hands,
link |
it actually will reduce your fluidity of speech.
link |
And so I'm going to put them back in front of me now.
link |
The point is smoking marijuana or consuming marijuana
link |
by edible changes one's speech
link |
and does it in a very specific way.
link |
And in this study by Adam Vogel and colleagues,
link |
they explored a huge different variety of aspects of speech.
link |
And this can be done using spectral processing,
link |
which is fancy nerd speak
link |
for looking at how much inflection there is
link |
or looking at how long people hold vowels
link |
or consonants, et cetera.
link |
And again, these are people
link |
not under the influence of cannabis,
link |
but rather people who tend to be
link |
under the influence of cannabis
link |
when not participating in the study.
link |
In other words, chronic recreational cannabis users.
link |
So what are the two major shifts that cannabis causes
link |
on our patterns of speech?
link |
Well, the first one is a change
link |
in what's called spectral tilt.
link |
And that's fancy nerd speak for vocal effort and intensity.
link |
So I'm not a pot smoker, I confess,
link |
but if I were to say the sentence,
link |
vocal effort and intensity
link |
are important components of speech.
link |
That's the way I would say that sentence
link |
if I was striving to enunciate very carefully
link |
and to accent certain words and syllables.
link |
A pot smoker or somebody who uses
link |
recreational cannabis fairly often
link |
would have reduced spectral tilt,
link |
AKA vocal effort and intensity,
link |
and might say spectral tilt is vocal effort and intensity,
link |
and it differed between groups
link |
and appeared to change in line
link |
with the duration of abstinence from cannabis use.
link |
That I think is not a far cry
link |
from the change in spectral tilt that they observed here.
link |
In addition, there are changes in verbal timing.
link |
That is pronunciation of words and accenting
link |
particular syllables of words
link |
in people that consume cannabis or smoke cannabis.
link |
So rather than emphasize particular words within a sentence,
link |
so again, I'll just use a sentence from the paper
link |
so that you can gain more knowledge from the paper.
link |
Cannabis, and I'll say it the way that I would say it,
link |
since I'm not a cannabis user.
link |
Cannabis, marijuana, is the most commonly used
link |
illicit drug in the world
link |
with approximately 4% of adults
link |
aged 15 to 64 years reporting recent use.
link |
And the citation is from the United Nations
link |
Office on Drugs and Crime, 2019.
link |
So that would be the way
link |
that I would typically read that sentence.
link |
And having gone into the data on this paper
link |
and of course evaluated references therein
link |
and listened to some of the spectral analysis
link |
that they include as data,
link |
you can literally go into these papers online
link |
and hear recordings of people who are cannabis users
link |
or non-cannabis users.
link |
And I'll try and give you a clear sense
link |
without picking an extreme example
link |
of how somebody who's a fairly consistent
link |
or even occasional cannabis user
link |
might read that very same sentence.
link |
Cannabis, marijuana, is the most commonly used
link |
illicit drug in the world
link |
with approximately 4% of adults
link |
aged 15 to 64 years reporting recent use.
link |
And the citation comes from the United Nation
link |
Office on Drugs and Crime, 2019.
link |
Now you'll notice that wasn't a dramatic difference.
link |
And of course I could have taken the liberty
link |
to pick an extreme example of the sort
link |
that they did occasionally observe
link |
in evaluating subjects for this paper.
link |
I could have said something like cannabis,
link |
marijuana is the most commonly used illicit drug,
link |
but frankly that would have been
link |
selecting an outlier example.
link |
And I don't want to do that.
link |
I don't want to skew the data as they say.
link |
Rather, if you heard the first time I read the sentence
link |
and the second time I read the sentence,
link |
what's mainly different is the difference
link |
in the amount of enunciation
link |
and accenting of particular words
link |
and symbols within a sentence.
link |
So the total content that's delivered is exactly the same.
link |
And while I wasn't measuring my pace,
link |
the overall rate of communication is essentially the same,
link |
but there's less sort of lilting
link |
and falling of the voice and less accenting.
link |
That's the major consistent effect of cannabis use.
link |
Now, of course, there are examples of people
link |
who are using a lot of cannabis
link |
and it impacts brain centers involved in movement and speech
link |
so much so that they really do have
link |
the really drawn out kind of nah.
link |
And oftentimes this will be detected in the laugh.
link |
You know, there's this sort of stereotypical stoner laugh
link |
as it's sometimes called rather than say ha ha ha,
link |
or that's a fake laugh, obviously.
link |
It's hard to make myself laugh
link |
if something's not actually funny.
link |
I'll have to think of something funny
link |
when people will say ha,
link |
like that's a bit more of the way I might laugh,
link |
like ha, sort of the inspiratory laugh
link |
or the ha, which is expiratory laugh.
link |
People who use cannabis chronically
link |
will often do the ah, right,
link |
which is sort of the back of the throat, ah.
link |
It's sort of the, it's neither inspiratory
link |
nor expiratory laugh.
link |
And believe it or not, there's an entire literature
link |
on inspiratory inhaling versus expiratory laughs.
link |
And there's also a literature on cannabis
link |
altering the pattern of inspiratory and expiratory laughs.
link |
It almost sounds like a sarcastic laugh
link |
when in fact they may not be feeling sarcastic at all.
link |
And I have a very close friend and colleague
link |
who's a phenomenal neurosurgeon and neuroscientist
link |
by the name of Dr. Eddie Chang.
link |
He's the chair of neurosurgery at UCSF and his lab
link |
and him are expert in the study
link |
of neuroscience controlling language and speech.
link |
And he often tells me that he can predict
link |
with almost certainty whether or not somebody
link |
is a regular cannabis user
link |
based not just on the patterns of speech that they use,
link |
but even just by recording specific neurons in their brain
link |
that underlie the laugh reflex
link |
and certain patterns of speech.
link |
So this idea that cannabis use changes your ability
link |
to speak and enunciate clearly does appear to be true.
link |
And the stereotype that cannabis use
link |
tends to create more of a drawl
link |
or kind of a, if you will, a laziness in the laugh
link |
and some of the reflexive enunciations that people use
link |
does also appear to be true.
link |
And I say all that of course with the caveat
link |
that many people out there will know individuals
link |
or perhaps you yourselves are individuals
link |
that may use cannabis, but that have incredible articulation
link |
probably better than mine
link |
and better than other people out there
link |
who speak for a living.
link |
So I'm not saying that 100% of people
link |
that use cannabis regularly can't speak well or clearly.
link |
That's simply not what I'm saying.
link |
And I don't want to communicate that idea at all.
link |
But it is the case that people who are regular cannabis users
link |
are impacting the neural circuits involved
link |
in movement, movement also controls speech
link |
and therefore cannabis is impacting speech.
link |
Now I'd like to turn our attention to whether or not
link |
cannabis can increase sexual activity,
link |
sexual desire and or sexual function.
link |
So we're going to be talking about libido,
link |
about sexual desire and about effects of cannabis
link |
And while this might sound like a discussion
link |
that's purely oriented towards recreational use of cannabis,
link |
that is people using cannabis to heighten
link |
or increase their sense of arousal for sexual activity.
link |
It actually ventures into the clinical realm too,
link |
meaning there have been excellent peer-reviewed studies
link |
that I'll describe to you in a moment
link |
exploring the use of cannabis or THC more specifically
link |
for something called hypoactive sexual desire disorder,
link |
which refers to a persistent or recurrent deficiency
link |
or absence of sexual fantasies and thoughts
link |
and or desire for or receptivity to sexual activity.
link |
This is a disorder that is fairly common,
link |
anywhere from six to 9% of people, both males and females.
link |
It used to be considered higher prevalence in females
link |
than in males, but now those numbers seem to be evening out.
link |
So basically there are anywhere from six to 9%
link |
of people out there who have very diminished sexual desire.
link |
And so a number of those people are interested
link |
in figuring out ways to increase their amount
link |
And of course there are people in the general population
link |
who may not have hypoactive sexual desire disorder
link |
who are interested in using cannabis recreationally
link |
in order to increase their desire for
link |
or their experience of sexual activity.
link |
Now, first we have to acknowledge that sexual desire
link |
and activity is a complex set of processes,
link |
meaning it's not just one event, sex, the verb,
link |
it involves arousal, it involves sex, the verb,
link |
and it involves a whole set of mindsets and emotional states
link |
that vary tremendously between individuals.
link |
But once again, we can distill out a few basic principles
link |
and I should emphasize these are by no means
link |
the only chemicals in neural circuits involved
link |
in the sexual arc, as we'll call it,
link |
desire, the act of sex, et cetera,
link |
but they are central to it, they are vital to it.
link |
They would be considered what I would call necessary
link |
but not sufficient, okay?
link |
So there'll be other chemicals involved too,
link |
but the main chemicals in neural circuits
link |
are those involved in dopamine.
link |
So the so-called mesolimbic reward pathway,
link |
in particular a brain structure called nucleus accumbens,
link |
which we'll talk about more in a moment,
link |
is vital to all motivated behaviors
link |
and to the seeking out of all particular types
link |
of pleasurable experiences and sex is no exception.
link |
So when we hear that the nucleus accumbens is activated,
link |
that almost always means that dopamine has been released
link |
in that area and other areas of the brain and body,
link |
and we can consider dopamine central
link |
to the desire for pursuit of end act of sex.
link |
In addition to that, there are molecules like oxytocin,
link |
which are involved in pair bonding,
link |
and they're going to be neural circuits
link |
specific to the oxytocin circuitry,
link |
but in terms of sexual arousal and sexual behavior,
link |
it's really the dopamine pathway in this nucleus accumbens,
link |
which are especially vital.
link |
That allows us to address the question,
link |
does cannabis increase, decrease,
link |
or have no effect on sexual desire
link |
and or the ability to have sex?
link |
And therein, we will find some very interesting answers
link |
because once again, it will point to the fact
link |
that the effects of cannabis on different individuals
link |
can be highly divergent, meaning in one set of individuals,
link |
cannabis will make them far less anxious,
link |
and in another set of individuals,
link |
the same strain of cannabis at the same dosage
link |
will make them extremely anxious,
link |
the same can be said also of sexual activity.
link |
And this was beautifully illustrated
link |
in the context of sexual desire
link |
in the journal Psychopharmacology
link |
in a paper published in 2017.
link |
The title of this paper is Individual Prolactin Reactivity
link |
Modulates Response of Nucleus Accumbens to Erotic Stimuli
link |
During Acute Cannabis Intoxication, an FMRI pilot study.
link |
So I'll give a little bit of definition
link |
to some of the terms in the title
link |
that will make it easier for you to understand the paper,
link |
but then I'll just march through the results
link |
because they are very straightforward and easy to understand
link |
and very interesting.
link |
FMRI is just functional magnetic resonance imaging.
link |
So basically, subjects in this experiment
link |
came into the laboratory.
link |
They were either people who had not used cannabis before
link |
or who had used cannabis before.
link |
They were placed into a brain scanner,
link |
one of these FMRI devices.
link |
It looks like a tube that people are backed up into
link |
and then they can view images in there
link |
and their brain can be imaged
link |
without having to remove any skull or drill into the skull,
link |
The participants in this study were grouped
link |
according to whether or not they'd experienced
link |
any aphrodisiac effects
link |
during the intoxication with cannabis.
link |
So that would be the first group, group A.
link |
They literally called it group A for aphrodisiac.
link |
And then the second group,
link |
and this is the only thing I don't like about this study,
link |
is rather than call it group B,
link |
they called them group non-A,
link |
which just gets a little confusing.
link |
So I'll try and simplify all this.
link |
There are two groups
link |
and one group experiences sexual arousal
link |
when under the influence of cannabis, THC specifically.
link |
The other group does not.
link |
And it turns out this is a very commonly observed
link |
divergence of effects of cannabis.
link |
Some people experience a lot of sexual arousal
link |
from cannabis and THC in particular,
link |
and some people do not.
link |
In fact, they experience suppression of sexual desire.
link |
And it's always been a little bit mysterious
link |
as to why that is.
link |
Well, in this study,
link |
they showed people in both groups erotic images,
link |
and they measured sexual arousal
link |
through a number of different measures.
link |
We won't go into all that.
link |
It was largely subjective.
link |
There've been other studies
link |
where they've actually measured things like erections
link |
in males and vaginal lubrication in females,
link |
the so-called autonomic responses
link |
that people can't lie about, so to speak,
link |
and that tap into other aspects
link |
of the so-called sexual arousal process.
link |
In this study, they also took blood samples
link |
to look at the concentration of things like cannabinoids.
link |
So this is a really nice study
link |
in that they actually measured how much THC
link |
was in the bloodstream in different individuals
link |
who reacted to these erotic stimuli in different ways.
link |
And they measured hormones, namely cortisol,
link |
which is a stress hormone,
link |
which tends to negatively correlate
link |
with sexual arousal and prolactin.
link |
And the interesting takeaway from the study
link |
was that for people,
link |
and it didn't matter if it was males or females,
link |
because they looked at both,
link |
for people that experienced elevated prolactin levels
link |
under cannabis intoxication, that's how they referred to it.
link |
People take cannabis, they measured prolactin.
link |
Some people had elevated prolactin, some people did not.
link |
For the people that had elevated levels of prolactin,
link |
they did not observe activation of brain areas
link |
associated with sexual arousal,
link |
in this case, the right nucleus accumbens.
link |
So you have two nucleus accumbi, I guess they'd be called,
link |
one on each side of the brain.
link |
And the activation of that brain area
link |
is strongly associated with dopamine and with arousal
link |
and sexual arousal in particular in this study.
link |
And if people had elevated prolactin,
link |
they did not experience activation of nucleus accumbens
link |
and they did not report feeling sexually aroused
link |
to those pictures,
link |
at least not to the same degree as the other group.
link |
So some people's prolactin levels go up
link |
when they ingest cannabis
link |
and those people do not achieve elevated levels
link |
of sexual arousal when under the influence of cannabis,
link |
even if they're looking at erotic stimuli.
link |
That makes sense because prolactin
link |
is mutually inhibitory, as we would say.
link |
It's kind of in a push-pull with dopamine.
link |
When dopamine levels are high,
link |
prolactin levels tend to be low.
link |
And when prolactin levels are high,
link |
dopamine levels tend to be low.
link |
The other group, so-called group A,
link |
that experienced elevated levels of sexual arousal
link |
when under the influence of cannabis
link |
and viewing erotic stimuli,
link |
that group did not show elevated levels of prolactin
link |
in response to cannabis.
link |
So this, I believe,
link |
resolves a longstanding controversy in the field,
link |
which is does cannabis increase sexual arousal?
link |
If you fall into the category of person
link |
who has elevated levels of prolactin in response to cannabis,
link |
then no, actually cannabis will suppress
link |
your sexual response and desire.
link |
If, however, you are in the category of person
link |
that does not have elevated levels of prolactin
link |
in response to cannabis,
link |
well then erotic stimuli can potentially,
link |
and in fact do, increase sexual arousal
link |
in the majority of individuals.
link |
Now, many of you are probably hearing this
link |
and wondering whether or not you fall into
link |
one category of individual or another.
link |
And the key thing here to understand
link |
is that levels of prolactin heading into the study
link |
did not predict, did not predict,
link |
whether or not people would respond to cannabis
link |
with elevated or non-elevated
link |
or even reduced levels of sexual arousal.
link |
It was whether or not people's prolactin levels went up
link |
or did not go up that predicted
link |
whether or not their levels of arousal would go up or not.
link |
So if you are somebody who, yes,
link |
does experience elevated levels of sexual arousal
link |
and function when under the influence of cannabis,
link |
well, that's very likely that cannabis
link |
does not increase your prolactin levels,
link |
at least not to a significant degree
link |
while you're taking it.
link |
And if you are somebody who does not experience
link |
increases in sexual arousal or function
link |
or even diminished sexual arousal and function
link |
when under the influence of cannabis,
link |
it's very likely the cannabis
link |
is increasing your levels of prolactin.
link |
Unfortunately, there's no way to know or predict
link |
based on some other measure.
link |
I think the outcome measure that is increased
link |
or not increased or even reduced sexual arousal
link |
is really the litmus test by which one can figure that out.
link |
While we are on the topic of the effects of cannabis
link |
on sexual function and hormones like prolactin,
link |
it's probably worth mentioning
link |
that cannabis has been studied extensively
link |
for its impact on other hormones.
link |
And we can summarize those literature in the following way.
link |
And here I'm referring to studies only on adults.
link |
We will talk about the developing brain and body
link |
in a little bit, but it is very clear
link |
that smoking cannabis increases prolactin levels.
link |
Now you might say, didn't you just describe a study
link |
about a set of individuals whose prolactin didn't increase
link |
and as a consequence, their level of sexual desire went up?
link |
Yes, there are a subset of individuals
link |
for which that's true.
link |
But people who smoke cannabis do experience increases
link |
in prolactin and that's especially pronounced
link |
in people that smoke cannabis more than twice a week.
link |
So this is important.
link |
Prolactin, as I referred to earlier,
link |
is reciprocal or mutually inhibitory with dopamine.
link |
One way to think about this is in the context
link |
of the normal sexual arousal arc
link |
whereby dopamine is increased
link |
when people are sexually aroused,
link |
but then after orgasm, both in males and females,
link |
prolactin levels skyrocket.
link |
This is actually what creates the so-called refractory period
link |
for males during which they cannot achieve erection again
link |
for some period of time.
link |
That relates directly to how long
link |
the prolactin increase lasts, okay?
link |
Prolactin is also increased in new parents of all species,
link |
including humans, which at least partially explain
link |
some of the reported or typical reductions
link |
in sexual desire and activity in new parents.
link |
Now there are other reasons for that too, sleep deprivation,
link |
but nature is smart and has arranged a set of hormones
link |
and circuits in the brain and body
link |
such that when tending to a newborn
link |
is the most important thing, it relegates,
link |
it reduces the importance of producing more children
link |
and sexual activity in those moments
link |
and days and weeks, sometimes longer.
link |
So when prolactin levels are up, dopamine levels are down.
link |
Smoking marijuana more than twice a week
link |
significantly increases prolactin.
link |
There are fewer studies exploring whether or not
link |
edible marijuana has the same effect,
link |
although the preliminary evidence suggests that it does not.
link |
I get into this in a lot more detail in a future episode,
link |
all about hormones with Dr. Kyle Gillette,
link |
who's been on this podcast before,
link |
but he verified that and my read of the literature
link |
is that the edible forms of marijuana,
link |
cannabis, probably, again,
link |
let's put an asterisk next to this,
link |
but it appears do not have as much
link |
of a prolactin elevating effect
link |
and therefore not as much of a dopamine suppressive effect
link |
and therefore not as much
link |
of a testosterone suppressing effect.
link |
And that gets to the issue of testosterone.
link |
Does cannabis marijuana suppress testosterone?
link |
And this is a very controversial literature and here's why.
link |
Some studies say, yes, it suppresses testosterone
link |
in males and females.
link |
And keep in mind that testosterone in females
link |
is vital for libido and cognitive function,
link |
cellular repair, et cetera.
link |
So it's not just important in males, of course.
link |
However, other studies say that cannabis
link |
does not decrease testosterone.
link |
And it seems to depend on whether or not
link |
the cannabis is brought into the system
link |
by way of smoking or edible.
link |
And it seems to depend on whether or not the cannabis
link |
is used chronically by an individual or acutely.
link |
And here, I just want to zoom out and say that studies
link |
on cannabis or drugs of any kind in humans
link |
are really complicated.
link |
If you think about it,
link |
someone has to come into the laboratory.
link |
And let's say you want to study chronic cannabis use.
link |
Well, you can't keep them in the laboratory all the time.
link |
So you have to rely on their self-report
link |
of how often they use cannabis and in what form.
link |
And you can't really control from one individual
link |
to the next of how much cannabis and THC
link |
they're bringing into their system.
link |
One person might smoke cannabis out of a bong
link |
and take big, deep lungs full bong inhalations or such.
link |
Other people might smoke joints.
link |
Other people might use edibles.
link |
It becomes very complicated to know what people have done
link |
and that they're reporting it accurately.
link |
And no joke here, especially if marijuana
link |
is impacting the short-term memory systems.
link |
They might not actually remember.
link |
They might not be tracking it that well.
link |
Contrast that with studies of the acute use of cannabis
link |
and THC, where people who are not regular users
link |
come into the laboratory.
link |
And now suddenly with institutional guidelines
link |
and safety protocols are under the influence
link |
of THC and cannabis.
link |
Well, now you're dealing with a person
link |
who may not have experience with the elevated heart rate
link |
and blood pressure that's characteristic of cannabis
link |
because it is a stimulant,
link |
at least when initially brought into the system,
link |
even if it might eventually lead to relaxation.
link |
So now you've got someone who's anxious
link |
or somebody who's not anxious, who's deeply relaxed,
link |
and you're trying to study these effects.
link |
So it's a moving target of sorts.
link |
It's very complicated to study marijuana and cannabis
link |
and its various derivatives in this way.
link |
Now you can probably appreciate better
link |
as to why there's so little nuanced data
link |
about sativa versus indica
link |
versus different ratios of CBD and THC.
link |
It's really difficult to do these studies
link |
in the first place.
link |
That said, the general rules are smoking marijuana
link |
increases prolactin in men and women,
link |
which will reduce dopamine and testosterone.
link |
Smoking marijuana chronically,
link |
meaning more than twice a week,
link |
does appear to reduce testosterone significantly
link |
and elevate so-called aromatase enzymes,
link |
which are the enzymes that convert testosterone
link |
This might partially explain the effect
link |
that occurs in about 35% of males,
link |
which is gynecomastia,
link |
which is a development of breast tissue in males,
link |
in particular young males
link |
who have elevated levels of testosterone
link |
or who are taking exogenous testosterone
link |
for testosterone replacement therapy,
link |
or if they're taking high doses, anabolic steroids,
link |
or in females, the increase in breast size,
link |
which is due to additional estrogen
link |
from testosterone converted to estrogen.
link |
So it does appear that marijuana and cannabis
link |
increase estrogen, reduce testosterone,
link |
increase prolactin, especially in chronic users.
link |
Now I'm sure that some people out there will say,
link |
well, their testosterone levels are exceedingly high
link |
meaning the constellation of symptoms
link |
associated with low testosterone and elevated estrogen
link |
are not present in them.
link |
That probably means one of two things or both.
link |
They either had elevated levels of testosterone
link |
to begin with, so their ceiling was higher,
link |
so bringing it down didn't have that much of effect,
link |
or that they have very low levels
link |
of aromatase in their system.
link |
There are some anecdotal evidence
link |
that smoking particular parts of the marijuana plant,
link |
in particular the seeds,
link |
can increase aromatase
link |
in the conversion of testosterone to estrogen.
link |
I think in the old days,
link |
the lower was the seeds make you sterile,
link |
and I think that was related to what I just told you,
link |
this increase in conversion of testosterone to estrogen.
link |
There's a vast literature
link |
on the effects of cannabis on fertility.
link |
It does seem, yes, it does seem to alter sperm motility
link |
and sperm health and function
link |
when taken chronically more than twice per week,
link |
in particular high doses of high potency THC.
link |
This is something we will cover in far more detail
link |
on a future episode all about fertility.
link |
And in females, there's an increase in estrogen
link |
as a consequence of smoking marijuana
link |
and increasing prolactin and estrogen in parallel.
link |
Whether or not that's detrimental isn't clear,
link |
although I point out that elevated estrogen and prolactin
link |
can be associated, again, can be associated,
link |
not necessarily, and certainly not causative,
link |
but can be associated with elevated levels
link |
or frequency of breast cancer detection.
link |
So cannabis and its effects on hormones
link |
are not without consequence.
link |
There are effects of cannabis on cortisol.
link |
In some individuals, it greatly increases cortisol
link |
due to the anxiety and paranoia it can create,
link |
and in other individuals, it reduces cortisol.
link |
Again, we have these divergent effects,
link |
but I want to be very clear.
link |
The effects on prolactin, meaning elevated prolactin,
link |
the effects on testosterone, meaning,
link |
at least most studies point to reduced levels of testosterone
link |
and increased estrogen,
link |
that seems to be true for most all individuals
link |
that chronically use cannabis.
link |
Whereas the effects on cortisol tend to be divergent,
link |
cannabis increases cortisol in some individuals
link |
and decreases cortisol in others.
link |
In general, increases in cortisol that are ongoing
link |
are not healthy for us and so on.
link |
And then of course, there are other effects on hormones,
link |
and I'll just briefly summarize those,
link |
that THC in particular, not CBD, but THC in particular,
link |
is known to be strongly inhibitory
link |
for something called gonadotropin-releasing hormone.
link |
This is a hormone that's released from the brain,
link |
from the hypothalamus, that then feeds onto,
link |
or I should say, signals to the pituitary gland,
link |
which is also near the roof of your mouth.
link |
A lot of stuff happening near the roof of your mouth,
link |
it turns out, biologically.
link |
And reduced levels of gonadotropin-releasing hormone
link |
caused by cannabis use,
link |
reduced levels of LH, luteinizing hormone, and FSH,
link |
which reduce levels of testosterone
link |
and sperm production in males,
link |
and egg health and ovulation
link |
and menstrual function in females.
link |
Now, I'm sure there are a number of women out there
link |
who will say they have perfectly normal menstrual cycles
link |
despite using cannabis.
link |
I'm certainly not going to dispute that.
link |
But if you are somebody who's trying to maximize fertility
link |
or regulate or balance hormones,
link |
marijuana and cannabis reduces GnRH,
link |
that is the gonadotropin released from the hypothalamus,
link |
and thereby reduces luteinizing hormone
link |
and follicle-stimulating hormone,
link |
which are released from the pituitary
link |
and travel in the bloodstream
link |
to support normal ovarian function and health
link |
and normal testicular function and health
link |
in females and males, respectively.
link |
Up until now, I've been discussing the biological
link |
and psychological effects of cannabis.
link |
Now, I'd like to shift our attention
link |
to some of the negative health effects of cannabis
link |
and shine light on some of the individuals
link |
or groups out there that need to be especially wary of
link |
and probably avoid cannabis use entirely,
link |
including ingestion of cannabis by way of edible.
link |
And I frame things that way
link |
because I think there is an increasingly large number
link |
of people out there that appreciate
link |
that smoking tobacco or smoking cannabis,
link |
vaping tobacco, yes, vaping tobacco or vaping cannabis,
link |
each and all have negative health consequences
link |
on the lungs and on the so-called endothelial cells
link |
of the body, the cells that make up the vasculature,
link |
the capillaries and blood vessels.
link |
If you don't already know this,
link |
I'll make it very clear and I'll make it very brief.
link |
Whether or not you smoke or vape tobacco or cannabis,
link |
you are severely impairing the function
link |
of endothelial cells that make up the capillaries
link |
and blood vessels of your brain and body.
link |
And that is known to decrease cognitive capacity over time,
link |
increase probability of strokes,
link |
severely impact lung function,
link |
and also lead to things like peripheral neuropathies.
link |
It leads to sexual dysfunction
link |
because of lack of blood flow to the genitals,
link |
can lead to other aspects of reproductive damage,
link |
including to the ovaries and testes.
link |
Essentially, there is no other way to state it
link |
except that smoking and vaping
link |
have negative health consequences
link |
that are independent of the substances
link |
that people are trying to get into their bloodstream
link |
by smoking or vaping.
link |
So people smoke and vape tobacco
link |
and people smoke and vape cannabis.
link |
And in both cases,
link |
if we just set aside the direct effects of tobacco
link |
and the direct effects of cannabis,
link |
we can confidently say that the process of smoking,
link |
of inhaling smoke into the lungs,
link |
and yes, also vaping,
link |
bringing the chemicals that transport nicotine,
link |
or in this case, cannabis into the lungs by way of vaping,
link |
are both severely detrimental to endothelial cells.
link |
I think a few years ago when vaping wasn't as prominent,
link |
there was this question and this idea
link |
that maybe vaping was going to be far healthier
link |
or at least not as bad as smoking,
link |
but now we can see a huge number
link |
of negative health effects of vaping,
link |
some of which are distinct from the effects of smoking.
link |
So if you'd like more information on smoking versus vaping,
link |
please see the episode that I did on nicotine.
link |
We will also do an entire episode
link |
all about vaping in the future,
link |
but there's really no way to slice it and dice it
link |
The fact of the matter is that smoking has clear
link |
and severe negative health consequences,
link |
regardless of whether or not you're smoking tobacco
link |
and vaping has negative health consequences,
link |
whether or not you're using the vape
link |
to bring in nicotine or THC
link |
or some combination of THC and CBD.
link |
That's simply the way it is.
link |
With that said, now I'd like to focus our attention
link |
on the direct effects that cannabis has,
link |
either by way of THC action or by way of CBD action
link |
in terms of positive or negative health effects
link |
on the brain and body.
link |
And we're going to explore that first as a function of age.
link |
And the reason we're going to do that is related to a fact
link |
that I mentioned at the beginning of the episode,
link |
which is that the CB1 and the CB2 receptors,
link |
the two receptors for cannabis
link |
to which THC and CBD and CBN
link |
and all other psychoactive compounds in cannabis bind to
link |
to have their actions are present throughout development.
link |
Believe it or not,
link |
they are present very soon after conception
link |
and the CB1 and CB2 receptors actually play a critical role
link |
in the development of the fetus.
link |
Now you might wonder why that is
link |
because of course the developing fetus
link |
doesn't necessarily expect to see cannabis
link |
or to be exposed to cannabis and THC and CBD.
link |
But as you recall, endogenous cannabinoids are present
link |
in the adult brain and body
link |
and endogenous cannabinoids it turns out
link |
are also present in the developing fetus.
link |
In fact, endogenous cannabinoids are present
link |
at much greater levels than the developing fetus
link |
than they are after a child is born.
link |
And levels of endogenous cannabinoids
link |
actually go down across development.
link |
I find this really interesting.
link |
What this means is that endogenous cannabinoids
link |
and activation of the CB1 and CB2 receptors
link |
are an integral part of neural development.
link |
And this is going to become especially relevant
link |
in considering whether or not pregnant mothers
link |
should or should not use cannabis or CBD.
link |
And it also points to some very interesting biology
link |
in terms of how the brain develops
link |
and how the body develops.
link |
Now the development of the brain and nervous system and body
link |
is a fascinating and vast literature,
link |
certainly far too vast to cover in today's episode,
link |
especially at this late hour, as it were.
link |
But we will have a future episode
link |
all about brain development.
link |
In terms of the effects of cannabis,
link |
it's sufficient to say that cannabinoid receptors
link |
are present and active in the developing fetus.
link |
They are present and active in the newborn.
link |
They are present and active in adolescents.
link |
And across that time from conception until adolescence,
link |
endogenous cannabinoids are mainly responsible
link |
for the actions of those cannabinoid receptors.
link |
During that time, the cannabinoid receptors
link |
are having very specific effects
link |
that are distinct from their effects later in life.
link |
And those effects can largely be explained
link |
in terms of neural development.
link |
Again, we don't have time for an entire lecture on this now,
link |
but during development,
link |
your body was a collection of a bunch of cells.
link |
It's actually called a blastula,
link |
which means a ball of cells.
link |
And then those cells actually have to grow out connections
link |
and duplicate themselves.
link |
And this is a very interesting process
link |
by which neurons initially are situated far apart,
link |
and then they grow out connections
link |
and make contacts with one another.
link |
They remove certain connections,
link |
depending on what kind of life events you're exposed to.
link |
If you have a wonderful event early in life
link |
or a traumatic early life,
link |
those connections change, et cetera.
link |
The important point for today's discussion
link |
is that the CB1 receptor in particular
link |
is expressed on every neuron in the developing brain
link |
and has been shown to be important
link |
for every aspect of neural development,
link |
from the proliferation of cells,
link |
meaning getting enough cells to create a brain,
link |
to the outgrowth of the so-called axons,
link |
the little wires that connect up neurons with one another,
link |
to the steering, the direction
link |
at which those axons go in development, which is essential.
link |
And even so far as to explain the connections
link |
that form between neurons, the so-called synapses,
link |
and then how those synapses work.
link |
So the basic statement here is that endogenous cannabinoids
link |
and CB1 receptor activation are critical
link |
for every aspect of brain wiring and development.
link |
With that in mind, the statement I'm about to make
link |
is absolutely terrifying, at least to me,
link |
and frankly, it should be terrifying to you as well.
link |
And the statement is the current statistics
link |
on cannabis use in pregnant mothers
link |
is absolutely shocking.
link |
The most recent survey of pregnant mothers
link |
in the United States show that 15%, one five,
link |
15% of pregnant mothers report using cannabis
link |
in some form or another, either smoking it
link |
or more likely ingestion of an edible,
link |
because they are aware of the negative effects of smoking
link |
on the developing fetus, ingestion of an edible
link |
to increase THC and or CBD during pregnancy,
link |
which to me, I have to say as a developmental neurobiologist
link |
is frankly, it's scary.
link |
It's absolutely scary because that CB1 receptor
link |
is not just a minor player in neural development,
link |
it is absolutely central to every critical aspect
link |
of brain wiring and development.
link |
Now, the long-term implications
link |
or even the short-term implications of this 15%
link |
of mothers self-reporting the use of cannabis
link |
at some point during pregnancy are not yet known.
link |
This is, as we would say, it's an experiment that's ongoing,
link |
but I'd be remiss if I didn't point out these data
link |
and just implore you, please, please, please,
link |
if you are pregnant or considering getting pregnant,
link |
you're a cannabis user, whether or not you're using edibles,
link |
if you're a CBD user, please do whatever is necessary
link |
to not ingest cannabis or smoke cannabis
link |
or ingest CBD during pregnancy.
link |
Now, there may be certain clinical indications
link |
by which your physician and your OBGYN
link |
and the pediatrician that will eventually
link |
be the pediatrician for your child will prescribe CBD,
link |
although it's hard to imagine what those are.
link |
I contacted a number of different pediatricians and OBGYNs
link |
and not a single one said they would ever suggest
link |
and in fact would strongly discourage their patients
link |
from using cannabis during pregnancy.
link |
But I think that the advent of edible forms of cannabis
link |
and the combination of THC and CBD in certain products
link |
and the fact that most people view CBD as safer
link |
because it does not include as, or does not have,
link |
I should say, the psychoactive effects that THC does
link |
has led to a situation where you have 15%
link |
of pregnant mothers using cannabis
link |
at some point during pregnancy
link |
and maybe even frequently throughout pregnancy
link |
and the effects on the developing fetus
link |
are completely unknown,
link |
but recall that cannabis and THC and CBD out-compete,
link |
meaning they park in the receptor
link |
for endogenous cannabinoids
link |
and prevent endogenous cannabinoids
link |
from having their normal level and pattern of action.
link |
So this is absolutely critical.
link |
I cannot encourage you enough, or rather I should say,
link |
I cannot discourage enough the use of cannabis
link |
and any related compounds in cannabis,
link |
edible or smoked, certainly not smoked,
link |
but even edible during pregnancy.
link |
And certainly in breastfeeding lactating mothers,
link |
the same is also true.
link |
Recall that cannabis and THC and CBD
link |
are incredibly lipophilic.
link |
They are fat soluble and they get into cells very readily
link |
and they cross the blood brain barrier,
link |
they cross the blood placental barrier.
link |
So when I encountered this statistic,
link |
I had to kind of wipe my eyes a few times.
link |
I could not believe it.
link |
And yet I cross-checked that number
link |
with a few other studies.
link |
A few others have come in a little bit lower at,
link |
somewhere like 13 to 14%
link |
and a few have come in a little bit higher,
link |
but the average of 15% is both striking and shocking.
link |
So I don't know how to make the message more clear.
link |
I hope that is clear.
link |
Please do not use any cannabis, THC or related things,
link |
including CBD, smoked or edible.
link |
If you're pregnant, lactating, et cetera.
link |
Now we are at the point where we need to consider
link |
some of the negative health effects of cannabis
link |
that have been well-documented in peer-reviewed studies.
link |
And before I do this,
link |
I want to return to a point that I made earlier,
link |
which is that nothing that I am about to say
link |
relates directly to issues of legality.
link |
If we consider alcohol, for instance,
link |
alcohol is legal in most areas of the world.
link |
It's certainly legal in the US
link |
and yet there's an age limit for its use.
link |
Typically it's not available to people
link |
until they're 21 or older.
link |
It's not to say that certain people don't use it
link |
before age 21, but it's not legal.
link |
It is illegal to buy or possess alcohol,
link |
consume alcohol before age 21.
link |
And I think with good reason,
link |
because the brain is still developing.
link |
Likewise, we can have a informed discussion about cannabis
link |
and its various components
link |
that can fully acknowledge the reality,
link |
which is that one of the major harms of cannabis in the past
link |
has been the legal ramifications of cannabis being illegal.
link |
That's a statement that is no longer controversial.
link |
And this is not a discussion about legalization
link |
or non-legalization.
link |
If you look to the scientific literature,
link |
the epidemiological literature,
link |
there are wonderful data out of Carleton University
link |
and elsewhere in Canada showing that
link |
many of the negative effects of marijuana
link |
and THC are due to the criminal justice system itself.
link |
That is the creation of illicit drug businesses,
link |
the creation of organized crime,
link |
the creation of a number of different features
link |
related to the illegality of cannabis.
link |
And again, this isn't the topic of today's episode,
link |
but that should be acknowledged.
link |
And at the same time, we need to acknowledge that
link |
when a compound, a drug or whatever you want to call it,
link |
becomes legal, there's a tendency to assume
link |
that it's safe and safe for everybody.
link |
And with respect to cannabis and THC and perhaps even CBD,
link |
but certainly for THC and cannabis that's smoked or vaped
link |
or consumed in edible form, that is simply not the case.
link |
There are clear data pointing to negative health effects
link |
of cannabis use and THC use,
link |
which again is not to say that there are not
link |
positive effects on mood, anxiety, pain relief, et cetera.
link |
Those are out there and they exist,
link |
and we will mention some of those, of course,
link |
and we've talked about some of those,
link |
creativity, for instance, et cetera.
link |
But if we do not acknowledge the negative health effects
link |
that are documented in the literature,
link |
then we are overlooking some very important data,
link |
especially as it relates to the development of psychosis
link |
in certain individuals.
link |
So with that said, there are very strong data,
link |
and I will provide links to these resources,
link |
pointing to the fact that for people
link |
who are chronic users of cannabis,
link |
that is using it twice a week or more,
link |
that over time their levels of anxiety actually increase.
link |
And this is true even for individuals
link |
that are using strains of cannabis
link |
that while under the influence of cannabis, reduce anxiety.
link |
Over time, meaning over the course of 12 or more months,
link |
there is a well-documented effect
link |
of the anxiety relief that cannabis and THC initially brought
link |
being less and less potent.
link |
That is, people need to smoke more of it or ingest more THC
link |
in order to achieve the same level of anxiety relief.
link |
And in some cases, a switch from anxiety relief
link |
to increase in anxiety.
link |
And again, that's increase in anxiety,
link |
not just when the drug is not being consumed,
link |
but also while under the influence of the drug.
link |
Why would that be?
link |
We have to go back to our understanding
link |
of the CB1 receptor and the potency
link |
with which THC binds to that CB1 receptor.
link |
When THC is brought into the system over and over again,
link |
meaning twice a week or more,
link |
the binding of THC to that CB1 receptor
link |
eventually causes a sort of habituation or attenuation
link |
of the entire process of binding the receptor
link |
and creating the psychoactive effects.
link |
So initially it creates anxiety relief,
link |
but over time the affinity for the receptor doesn't change,
link |
meaning it can still park in that slot
link |
with a lot of affinity, a lot of strength,
link |
but there are fewer receptors available.
link |
And then the signaling that's downstream of those receptors
link |
becomes less and less robust.
link |
Now, this is a topic we didn't get into
link |
in too much detail today,
link |
because I didn't want to include even more biological detail,
link |
but the CB1 receptor
link |
is a so-called G protein-coupled receptor.
link |
That's a mouthful, but a G protein-coupled receptor
link |
basically is like a bucket brigade.
link |
So while some receptors in the brain and body
link |
are such that when something, a chemical binds to them,
link |
that receptor has a direct action,
link |
like it opens and allows stuff to rush into the cell,
link |
increases the excitability of the cell,
link |
so-called fast effects.
link |
These G protein-coupled receptors,
link |
and CB1 is a G protein-coupled receptor,
link |
they are more like a bucket brigade,
link |
where they kick off a process through one molecule
link |
that then is handed off to another molecule,
link |
that this then is handed off to another molecule.
link |
It's a long chain or cascade of events.
link |
Those long chains or cascades of events
link |
have a lot of opportunity for regulation, for adjustment.
link |
You know, receptor systems in the brain and body,
link |
especially receptor systems like the cannabinoid system
link |
that are used to being kind of tickled, not punched,
link |
you know, tickled by endogenous cannabinoids
link |
every once in a while, some binds, has an effect,
link |
but certainly not bound with incredible potency
link |
and over and over again,
link |
as they are when THC is coming into the system.
link |
Well, those systems, eventually over time,
link |
they adjust themselves so that the body and those cells
link |
can achieve so-called homeostasis.
link |
So when people are using THC more than twice a week,
link |
what ends up happening is those G protein-coupled receptors
link |
and the downstream signaling mechanisms
link |
start to adjust themselves,
link |
and it requires more and more drug,
link |
so either higher dosages or more frequent use.
link |
And a lot of the positive effects,
link |
the so-called decrease in anxiety,
link |
increased focus, increased creativity,
link |
some of that starts to wane.
link |
It starts to dissipate,
link |
and people wonder why they have to use so much cannabis
link |
just to achieve a fraction of the effect
link |
that they used to be able to achieve with even a lower dose.
link |
So anxiety is getting worse over time,
link |
and that's anxiety during the drug use
link |
and outside of the drug use.
link |
Some people work around that or try to work around that
link |
by using varying strains of cannabis
link |
or changing the pattern of delivery from smoking to vaping
link |
or from vaping to edible and from edible to transdermal.
link |
Anyway, they go through a lot of gymnastics
link |
and writhing and seeking,
link |
but nonetheless, anxiety increases over time.
link |
Also, it's very clear that depression increases over time,
link |
and especially, this is surprising to me,
link |
but especially for individuals that were not depressed
link |
at the outset of their use.
link |
In other words, they didn't start using cannabis
link |
because they were depressed,
link |
but rather the depression starts to emerge
link |
as a consequence of the cannabis and THC use.
link |
So that's serious.
link |
In fact, we now know,
link |
based on really solid epidemiological evidence,
link |
that depression is not a strong predictor
link |
of seeking out cannabis.
link |
It doesn't drive terribly many people
link |
to seek out cannabis use,
link |
but cannabis use itself makes people four times likelier
link |
to develop a chronic major depression.
link |
So anxiety is increasing, depression is increasing,
link |
and this turns out to be especially relevant
link |
and important to young people.
link |
Why do I say that?
link |
Well, if you look at the data,
link |
and again, I think some of the strongest data
link |
or data to come out of the Canadian system,
link |
they've done some really beautiful controlled studies.
link |
I really hope to invite some of the people
link |
who arranged and ran those studies
link |
as guests onto the Huberman Lab Podcast.
link |
But if you look at the data out of Canada
link |
or you look at some of the data
link |
out of Northern Europe and the US,
link |
what you find is that the probability
link |
that somebody will use cannabis
link |
and then go on to use it chronically
link |
correlates very strongly with age.
link |
So for instance, some of the highest degree of cannabis use
link |
is among individuals 16 to 24 years old.
link |
In fact, in individuals who are 16 to 24 years old,
link |
and in particular in students
link |
and people who are working, surprising,
link |
more than in unemployed populations,
link |
being young, 16 to 24, at least to me that's young,
link |
and being a student or working doubles the likelihood
link |
that somebody is going to use cannabis on a regular basis,
link |
twice or more per week.
link |
The typical age of initiating cannabis use nowadays
link |
is about 19 years old, so 18.7,
link |
and about 20% of people in that age bracket
link |
of 16 to 24 years old are using cannabis daily,
link |
either by vaping, by smoking, or by edible.
link |
That's an enormous number, at least by my read,
link |
it's an enormous number,
link |
and here's why it's of really serious concern.
link |
During the ages of 16 to 24,
link |
the cannabinoid receptors are still available.
link |
They are not being as strongly driven
link |
by endogenous cannabinoids,
link |
but by ingestion of THC and or CBD,
link |
there are downstream effects
link |
on the signaling within those cells
link |
that all the data point to creating
link |
a much, much higher likelihood
link |
of developing major depression, severe anxiety,
link |
or psychosis at later ages.
link |
So to be very clear,
link |
cannabis use between the ages of 16 to 24
link |
in both males and females is increasing anxiety,
link |
increasing depression in the immediate years,
link |
and within the one year's time or so,
link |
so much so that people are using cannabis ongoing
link |
in an attempt to reduce that anxiety
link |
and reduce that depression.
link |
But in addition to that,
link |
and because of the signaling mechanisms involved,
link |
are predisposing those individuals
link |
to psychosis later in life.
link |
If you look at individuals who start using cannabis
link |
even younger, age 14, or even as young as 12,
link |
the probability of psychosis later in life,
link |
in particular schizophrenic or schizophrenic-like episodes,
link |
more than doubles.
link |
So this is a really serious concern,
link |
and this is completely aside
link |
from any so-called positive effects
link |
or beneficial effects of cannabis
link |
that people might derive from occasional use as adults,
link |
meaning people older than 25.
link |
So for the person who's older than 25,
link |
who eats an edible every once in a while,
link |
or who smokes cannabis every once in a while,
link |
and people love to make the argument,
link |
it's not as bad as alcohol,
link |
which frankly is a terrible argument,
link |
because if you saw our episode on alcohol,
link |
alcohol is pretty bad.
link |
But even so, it's just not a good argument.
link |
Saying that something is good
link |
because it's not as bad as something else
link |
is simply just not a good or valid argument,
link |
at least not biologically speaking.
link |
The use of cannabis in young populations
link |
is very strongly predisposing people to psychotic episodes.
link |
And we know the mechanism by which this occurs.
link |
This occurs by a thinning of the so-called gray matter.
link |
And it's called gray matter because with neurons,
link |
nerve cells, they have a so-called cell body.
link |
That's the part that contains the DNA
link |
and manufactures all the neurotransmitters, et cetera.
link |
And those are shipped out to the other parts of the neuron
link |
that include the axon, the wires between axons.
link |
And those axons under the microscope
link |
because they have a lot of fatty tissue around them,
link |
and this is healthy fatty tissue
link |
that allows electrical transmission to be fast.
link |
That fatty tissue, those portions of the cells
link |
are called white matter.
link |
So you have gray matter and white matter.
link |
Gray matter are the so-called cell bodies
link |
where the DNA and all this stuff is manufactured.
link |
White matter are the axons or the wires
link |
through which all the key components
link |
are shipped out to the synapse, et cetera.
link |
Wonderful data, and I do say wonderful
link |
because this is part of a large-scale consortium,
link |
and we will provide a link to the paper.
link |
This was published in Translational Psychiatry
link |
just this year, point to the fact
link |
that adolescent cannabis use accelerates the thinning
link |
of the prefrontal cortex and the gray matter in particular.
link |
So what this means is while during normal development,
link |
the gray matter, the prefrontal cortex,
link |
and all the cells there are indeed intended,
link |
it's a normal process for it to thicken
link |
and then thin a little bit as connections are adjusted
link |
and people learn and mature and grow up.
link |
This is part of the normal, healthy maturational process,
link |
independent of cannabis use.
link |
When kids, because these really are kids, use cannabis
link |
and it doesn't matter the mode of cannabis delivery,
link |
whether or not it's vaping or smoking or edible,
link |
that gray matter thins at a much, much greater rate.
link |
And the reason I like this paper published
link |
in Translational Psychiatry this year so much
link |
is that they link the amount of cannabis use,
link |
heavy, moderate, light, or no cannabis use
link |
to the rate of prefrontal cortical thinning.
link |
And it's absolutely clear from these data
link |
that the more often young people,
link |
meaning individuals between the age of 14 and 25,
link |
the more often they consume or smoke or vape cannabis,
link |
the faster and the more extreme that cortical thinning is.
link |
And the cortical thinning is occurring
link |
in exactly the area of the brain that's involved in planning,
link |
in control over one's emotions, in reflexes,
link |
in organizing one's life in a number of different ways,
link |
anywhere from cleaning one's room, literally,
link |
you know, knowing what goes where,
link |
to making plans that extend out through the day,
link |
through the week, through a year,
link |
essentially becoming a functional human being
link |
involves using your prefrontal cortex
link |
in a variety of different contexts
link |
and different sort of time domains,
link |
the time domain of an hour, the time domain of a day.
link |
Making plans and being able to execute plans
link |
is fundamental to being a healthy human being.
link |
And it's absolutely clear from these data
link |
that the more cannabis one uses,
link |
the more impaired those neural circuits are.
link |
There's simply no other way to view these data.
link |
In fact, so much so that even small amounts of cannabis use
link |
are associated with rates of cortical thinning
link |
and degrees of cortical thinning
link |
that are really detrimental and concerning
link |
for normal cognitive processes.
link |
If you were somebody who smoked marijuana
link |
or consumed cannabis in any form or another
link |
during adolescence,
link |
does that mean that your prefrontal cortex
link |
can never be rescued, that it can't come back?
link |
Well, the short answer is
link |
it probably can be rescued to some degree.
link |
It will depend on how much cannabis you were using
link |
and how often and what strains of cannabis, et cetera.
link |
There's really no traveling back in time.
link |
As my graduate advisor used to say,
link |
you know, time machines are broken.
link |
At least for now, we don't have time machines.
link |
So all you can really do is try and emphasize,
link |
first of all, quitting cannabis in any form
link |
and focusing on behaviors that emphasize endothelial cell,
link |
blood flow, health to the brain.
link |
So that would be cardiovascular exercise,
link |
adequate nutrition, not smoking nicotine.
link |
And there are a number of other things that one can do.
link |
We will do an entire episode
link |
all about trying to reverse the effects of cannabis
link |
and other drug use during adolescence.
link |
We don't have time to do a deep dive on that right now,
link |
but all the things that standardize
link |
and kind of promote health, adequate sleep,
link |
good social connection, regular cardiovascular
link |
and weight training exercise, healthy nutrition,
link |
what that represents to you,
link |
healthy metabolic function and weight, et cetera.
link |
Those are all going to facilitate some recovery
link |
of brain function in particular prefrontal cortical function
link |
by way of all the positive effects
link |
that those behaviors and choices have.
link |
But with that said, if you are in the age bracket
link |
that I've been referring to,
link |
this 14 to 25-year-old age bracket,
link |
and you are a occasional even or chronic cannabis user,
link |
you should be very, very careful and concerned
link |
about the long-term effects that could potentially have.
link |
That statement is bolstered by another statistic,
link |
which is that unlike a lot of other drugs,
link |
the rate of cannabis use is strongly related
link |
to how dangerous people perceive cannabis to be.
link |
And that might seem obvious on the one hand.
link |
If you think something is very, very dangerous,
link |
you would expect that the probability
link |
that somebody would use it would be very, very low.
link |
And if they think something is safe,
link |
the probability would be high.
link |
But that isn't necessarily the case.
link |
If you think about it, cannabis is a unique instance
link |
in which nowadays we are hearing,
link |
yes, it's becoming legal in a number of areas.
link |
And we talked earlier about
link |
why that's probably a good thing in most circumstances,
link |
but that we aren't just hearing that cannabis is safe,
link |
or it's not just being implied that cannabis is safer,
link |
but many more people are talking
link |
about the positive effects of cannabis
link |
without a lot of discussion
link |
about the negative effects of cannabis.
link |
And I realize that saying this
link |
is going to upset some people out there
link |
because I know that there are a number of people
link |
who fought very hard for the legalization process,
link |
and I want to acknowledge that.
link |
I also want to acknowledge
link |
the many known positive effects of cannabis in adults
link |
with very occasional use,
link |
provided it is delivered safely
link |
and in the safe context and setting and with legality.
link |
That is entirely distinct from the issue
link |
of whether or not cannabis is safe
link |
for the developing brain and body.
link |
Again, I'm not demonizing anybody for using cannabis,
link |
but I want to make the point very simply and very directly.
link |
It is far and away a different circumstance for the brain
link |
for an individual to be 25 years or older
link |
and using cannabis in whatever form occasionally,
link |
or maybe even frequently,
link |
than it is for a young person aged 14 to 25
link |
to be using cannabis either by smoking or vaping
link |
or by edible or any other form on the brain and body.
link |
It's absolutely clear that the brain continues to develop
link |
at least until age 25,
link |
and that a huge number of systems
link |
related to mood regulation, so-called executive function,
link |
the ability to organize one's thoughts,
link |
plan and execute plans,
link |
essentially to become a functional human being, right?
link |
That's one portion of becoming a functional human being,
link |
but certainly is an essential one.
link |
All of that relies on the fine tuning
link |
of this neural circuitry
link |
that we've been talking about up until now.
link |
And it's abundantly clear
link |
that cannabis and THC in particular
link |
dramatically disrupt those processes.
link |
So if this isn't clear enough just from my statements,
link |
I'd like to point to a particular paper.
link |
This is one of the more impactful papers
link |
in this area in recent years.
link |
This is a paper published in Lancet Psychiatry in 2022.
link |
Title is Association of Cannabis Potency
link |
with Mental Ill Health and Addiction, a Systematic Review.
link |
There are a number of very important points
link |
in this very fine paper.
link |
Lancet Psychiatry is one of the premier
link |
medical journals out there,
link |
and they evaluated a huge number of studies.
link |
They actually looked at more than 4,000 studies.
link |
They selected the ones that were only the most rigorous
link |
in terms of study design and analysis
link |
and rigor of conclusions.
link |
And they looked at how early use of cannabis
link |
impacted later probability of development of psychosis
link |
and other psychiatric conditions.
link |
And the takeaways from this study are very clear.
link |
First of all, chronic cannabis use,
link |
so more than twice per week,
link |
has consistently been associated
link |
with mental health disorders.
link |
I'm pulling some phrases directly from the paper.
link |
Heavy cannabis use,
link |
meaning cannabis use more frequent than twice per week,
link |
has been associated with four times the risk
link |
of psychosis later in life.
link |
In particular, schizophrenia and bipolar-like episodes.
link |
Now we've done an episode on bipolar disorder,
link |
so-called bipolar depression.
link |
We have not yet done one on schizophrenia,
link |
but both bipolar disorder and schizophrenia
link |
have a very, very strong genetic component.
link |
There's a 30, three zero, 30 times greater likelihood
link |
that you'll have bipolar disorder
link |
if you have a first relative who has bipolar disorder.
link |
And then it's also the case
link |
that using cannabis, especially during adolescence
link |
and the teen years and up until age 25,
link |
create a four times greater risk of psychosis
link |
for those that have a predisposition
link |
to bipolar disorder and or schizophrenia.
link |
Now, I don't hear very much about this in the media.
link |
This paper got some attention
link |
and then it sort of got swept away.
link |
I don't think that was an intentional sweeping way.
link |
There's just a lot of events in the world,
link |
But I think it's a particularly important set of findings
link |
because obviously in looking at so many studies,
link |
it distills out the strongest findings that are out there
link |
and really pulls the consistent messages
link |
that are arriving from all these different studies.
link |
And as they point out, and again, I'm paraphrasing here,
link |
this is the first systematic review
link |
of the Association of Cannabis Potency.
link |
And all of the data point to a very clear conclusion,
link |
which is the more potent the THC concentration,
link |
the higher probability of developing psychosis
link |
or a major depressive episode
link |
or a major anxiety disorder later in life.
link |
That should be of particular concern
link |
because we know we are absolutely clear
link |
about the fact that with the advent
link |
of all these new strains of cannabis
link |
and with the engineering and availability of cannabis
link |
at much higher potency, meaning THC potency,
link |
the risk of psychosis is going up and up
link |
and is likely to continue going up
link |
unless something is done to reduce
link |
the frequency of cannabis use to zero ideally
link |
or to very low frequency, very low potency
link |
in adolescents and teens and people aged 25 or younger.
link |
I know a lot of people don't want to hear this message
link |
because first of all, it's alarming.
link |
And second of all, as I mentioned earlier,
link |
the statistics tell us that the greatest number of people
link |
that are starting to use cannabis
link |
are in the age bracket of 16 to 24.
link |
Many of them are functional in other areas of life.
link |
They are students, they are employed, et cetera.
link |
But when you couple that with the fact
link |
that the most frequent adopters of cannabis use
link |
are in this age bracket of 16 to 24,
link |
they're twice as likely to use as other individuals
link |
or to start using cannabis as our other individuals.
link |
Plus the general perception out there
link |
because of the way that cannabis is discussed in the media
link |
and by sports figures and by celebrities
link |
and by politicians, et cetera,
link |
that it's not as bad as alcohol and maybe not that bad
link |
and maybe even has health benefits,
link |
then you're essentially setting up a system
link |
where young people are far more likely
link |
to adopt and continue cannabis use
link |
without realizing these serious health consequences
link |
that await them later.
link |
With all of that said, I of course, again,
link |
want to acknowledge that there have been
link |
well-demonstrated effects of cannabis for reducing pain,
link |
in particular in chemotherapy
link |
and in the context of reducing nausea
link |
in people suffering from cancer or chemotherapy.
link |
There is a well-known effect
link |
that one can generally point to as positive
link |
using cannabis for things like glaucoma,
link |
for lowering intraocular pressure
link |
and offsetting the loss of neurons
link |
that would lead to blindness.
link |
Although there are other tools, of course,
link |
that don't involve cannabis use
link |
that can accomplish that as well,
link |
so-called intraocular pressure-lowering drugs or drops.
link |
There is a list of probably a dozen or more
link |
psychological and bodily ailments
link |
that can be aided by cannabis use,
link |
in particular edible cannabis use of particular strains.
link |
Of course, I'm going to address each and every one of those
link |
in episodes where I'm talking, for instance,
link |
about eye disease or about chronic pain.
link |
I am in no way, shape, or form
link |
trying to rob the incredible efforts of the laboratories
link |
and people that have worked very hard
link |
to study and establish the valid uses of cannabis
link |
for treating various ailments
link |
and that continue to study cannabis
link |
in order to try and ameliorate
link |
the symptoms of different ailments.
link |
But today I really wanted to emphasize
link |
the biology of cannabis.
link |
Some of the often discussed effects,
link |
I guess one could call them positive effects,
link |
things like enhanced creativity
link |
and really point to the nuance
link |
and actually the divergence of people who take cannabis
link |
and some experience heightened levels of creativity
link |
Some people experience heightened levels of sexual arousal
link |
and some people experience the exact opposite
link |
and so on and so forth,
link |
rather than focus on all the potential positive
link |
and sort of emerging positive data about cannabis
link |
in different medical contexts.
link |
And at the same time,
link |
I strongly feel that it's important
link |
to acknowledge the shocking,
link |
because there's really no other way to describe it,
link |
the shocking effects of cannabis use
link |
on the developing fetus
link |
and the fact that so many pregnant
link |
and lactating mothers are using cannabis.
link |
I mean, that number 15% still has me dizzy
link |
with kind of disbelief
link |
and yet we need to acknowledge this
link |
and address this immediately.
link |
And I think it's vital to understand
link |
that cannabis use through any delivery mechanism,
link |
smoking or vaping or edible or otherwise
link |
is very, very concerning.
link |
In fact, dangerous to the developing brain,
link |
certainly for the fetal brain and for the baby brain,
link |
but also for the adolescent brain
link |
and for the teen and young adult brain,
link |
not just because of the effects that it can have
link |
in the immediate term,
link |
those slow creeping increases in anxiety and depression
link |
brought on by cannabis use,
link |
but also the time release, if you will,
link |
on the development of psychosis
link |
and other types of major psychiatric disorders
link |
I acknowledge we've covered a lot of ground today
link |
and yet there's still far more ground
link |
that we could have covered
link |
and that we will indeed cover in future episodes.
link |
Nevertheless, if you are learning from
link |
and are enjoying this podcast,
link |
please subscribe to our YouTube channel.
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That's a terrific zero cost way to support us.
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In addition, please subscribe to the podcast
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And on both Spotify and Apple,
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You can subscribe to that
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has partnered with Momentous Supplements.
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If you'd like to see the supplements
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you can go to Live Momentous spelled O-U-S,
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And there you'll see a number of the supplements
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I should just mention that that catalog of supplements
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If you haven't already signed up
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this is a monthly Huberman Lab podcast newsletter
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Many people find these very useful
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So for instance, if you go to HubermanLab.com,
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click to Neural Network newsletter or simply newsletter,
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We do not share your email with anybody.
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I cover many of the tools that are discussed
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Again, it's Huberman Lab on all platforms.
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So once again, thank you for joining me
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for today's discussion all about cannabis.
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And as always, thank you for your interest in science.
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I'll see you next time.