The Tim Ferriss Show Transcripts: Dr. Andrew Huberman — A Neurobiologist on Optimizing Sleep, Performance, and Testosterone (#521)

Please enjoy this transcript of my interview with Dr. Andrew Huberman (@hubermanlab), a neuroscientist and tenured professor in the Department of Neurobiology at Stanford University’s School of Medicine. Andrew has made numerous important contributions to the fields of brain development, brain function, and neural plasticity. He is a McKnight Foundation and Pew Foundation fellow and recipient of the 2017 Cogan Award for his discoveries in the study of vision. Work from the Huberman Laboratory at Stanford Medicine has been consistently published in top journals including Nature, Science, and Cell.

Andrew is host of the Huberman Lab podcast, which he launched in January of this year. The show aims to help viewers and listeners improve their health with science and science-based tools. New episodes air every Monday on YouTube and all podcast platforms. 

Transcripts may contain a few typos. With some episodes lasting 2+ hours, it can be difficult to catch minor errors. Enjoy!

Listen to the episode on Apple Podcasts, Spotify, Overcast, Stitcher, Castbox, Google Podcasts, or on your favorite podcast platform.

#521: Dr. Andrew Huberman — A Neurobiologist on Optimizing Sleep, Performance, and Testosterone


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Tim Ferriss: Hello, boys and girls, ladies and germs, this is Tim Ferriss. Welcome to another episode of the Tim Ferriss Show, where it is my job to interview world-class performers from all different disciplines to tease out the habits, routines, influences, life lessons, and so on that you can apply to your own lives. My guest today is Andrew Huberman. That’s H-U-B-E-R-M-A-N, PhD. You can find him on Twitter and Instagram at hubermanlab. Andrew is a neuroscientist and tenured professor in the department of neurobiology at Stanford University School of Medicine. He has made numerous important contributions to the field of brain development, brain function and neuroplasticity.

Andrew is a McKnight Foundation and Pew Foundation Fellow and recipient of the 2017 Cogan, that’s C-O-G-A-N, Award for his discoveries in the study of vision. Work from the Huberman Laboratory at Stanford Medicine has been consistently published in top journals, including Nature, Science and cell. Andrew is the host of the Huberman Lab podcast, which he launched in January of this year. The show aims to help viewers and listeners improve their health with science and science-based tools. New episodes air every Monday on YouTube and all podcast platforms. As mentioned, you can find him on Instagram and Twitter at hubermanlab. You can find him on the web at

Andrew, many people have been trying to matchmake for five or six years. And finally, here we are. Welcome to the show.

Andrew Huberman: Well, thanks so much for having me here. Yes. We’ve crossed paths, near misses for a long time, and it’s great to finally sit down and chat.

Tim Ferriss: I thought I would start right in your wheelhouse and use a headline to introduce the subject of vision. Scientific American interviewed you not long ago and they titled the piece, quote, Vision and Breathing May Be the Secrets to Surviving 2020, end quote. So breathing, I think for a lot of folks, might seem self-evident. Stop that, you have a lot of problems on your hands, or if you do it incorrectly. We can certainly dive into that later on. Vision, I think, will jump out as perhaps odd to a lot of folks. Why vision? Why is vision perhaps a secret or a key to surviving 2020, or any year for that matter?

Andrew Huberman: Yeah. The vision and our visual system is perhaps the strongest lever by which we can shift our state of mind and body. And that might at first come as a surprise because we think of vision as this thing that we have to see colors and motion and recognize faces, et cetera. But the two little goodies in the front of our skull, our eyes, are actually part of our central nervous system. So a lot of people don’t realize this, but your neural retina, the little light-sensing piece of the eyes in the back of the eye, kind of lines it like a pie crust, are actually two pieces of your brain that were deliberately squeezed out during early development. So they’re the only two pieces of your brain that are outside the cranial vault, as we say. And those little pieces of brain have an enormous impact on the state of the rest of your brain.

So it’s fair to say that what you see and how you view the world, literally, has an incredible impact on your state of mind. Respiration, breathing, also on your state of mind and body. But the reason is the following. Our visual system is not just for seeing objects, shapes, and colors, et cetera. Our eyes have two functions. So much in the same way that our ears are responsible for hearing, but also there’s a balance mechanism in there, our eyes are responsible for detecting shapes and colors, et cetera. But also for telling the rest of the brain whether or not to be more alert or more relaxed. And the most fundal fundamental way that our eyes do that is communicating time of day, the presence or absence of sunlight, to our central circadian clock. And then the central circadian clock, which is really just an aggregation of neurons, communicates to the rest of the brain and body whether or not, for instance, metabolism should be high or metabolism should be low, whether or not we should feel like moving or feel like lying down and not moving at all.

But there are a number of ways in which the visual system works on fast time scales to adjust our inner state. And one of the most simple ways that it does that is one that normally happens when we’re stressed or relaxed, but we don’t recognize it. So for instance, if we are very relaxed, our pupils change, the shape of our lens changes such that we actually have dilated vision. We see the entire environment we’re in, so-called panoramic vision. When we are stressed or we are excited about something, the pupils dilate, the shape of our lens changes. Literally, the optics of our eye changes, and the information about the outside world that’s delivered to the rest of our brain and body changes. The aperture of our experience, our entire experience, shrinks. We get so-called soda straw view of the world. We’re looking through soda straws, essentially, when we are alert or stressed. And we’ve experienced this, but we don’t normally notice it happening.

So much like breathing, our experience of life, whether or not we’re alert or stressed, excited or calm, changes our patterns of breathing. We’re all accustomed to that. Our breathing speeding up, or holding our breath in anticipation. But as well, our inner state drives changes in our visual system, the aperture of whether or not we see the big picture or we have a very contracted view of the world. But both of those things, breathing and vision, also run in reverse. Meaning, if we change our pattern of breathing, we change our inner state. If our state changes, our breathing changes. So it’s reciprocal. It’s bi-directional. Likewise with vision, when we’re excited or stressed, the aperture of our visual window shrinks. We get that soda straw view of the world. When we are relaxed, the aperture of our vision expands. But as well, it runs in both directions.

If we expand our view of the world, literally force our visual field, or just — it’s very easy, actually. You can do it no matter where you are right now. If you just try and expand your visual field, not by looking around or moving your head or eyes, but by trying to see yourself in the environment that you’re in. So you literally dilate your view so you could see the ceiling and the floor and the walls if you’re inside. Or if you’re outdoors, seeing as big an aperture of your visual field or your visual environment as possible.

Tim Ferriss: So you’re directing your attention to, even though you might remain looking straight ahead, you’re just directing your attention to as wide a peripheral view, horizontally and vertically, as possible? Is that what you mean?

Andrew Huberman: That’s right. Exactly. So essentially, if you keep your head and eyes mostly stationary, you don’t have to be rigid, you know, rock steady. But if you look forward and you expand your field of view, so you kind of relax your eyes so that you can see as much of your environment around you as possible to the point where you can see yourself in that environment, what you do is you are turning off the attentional and, believe it or not, the stress mechanisms that drive your internal state towards stress.

This is why when you go to a vista or you view a horizon, it’s very relaxing, because you naturally go into panoramic vision. When you are indoors, you’re looking at your phone, you’re looking at a computer or a camera or something of that sort, or you’re talking to somebody or an intense conversation, you may not notice it, but your entire visual field shrinks to a much smaller aperture, and that drives an increase in alertness and internal state. And we sometimes call that stress if it’s a negative experience. If it’s a positive experience, we might call that love or obsession or fascination.

But the important thing to realize is that both vision and breathing have a profound and very rapid effect on our internal state of mind and body, and it runs in both directions. Our internal state, that could be triggered by a text message or hearing something that somebody says, it drives changes in our breathing and our vision. But our breathing and our vision can also drive changes in our internal state. And so that article in Scientific American was a discussion about how we can leverage the visual system and the respiration, the breathing system, in order to take control over our internal state, because it’s not just that 2020 was stressful, it’s that our internal state determines everything. It doesn’t just determine if we feel like we’re having a hard time falling asleep, or we’re having a hard time focusing, for instance. It also determines how we batch time, how we analyze where we are in the world in terms of our lifespan.

A good example of this would be when we are very stressed, we fine-slice time. This is why when people are in a car accident or something, they might report that things were in slow motion. They’re actually, your frame rate increases. Whereas when you’re very relaxed, your frame rate slows down. And when we are relaxed, we get so-called perspective. We are able to say, “Well, this too shall pass.” Or, “I can place this stressful event in a context.”

So one thing that’s just fundamental to how our nervous system works is that we are constantly placing our experience, both our immediate and past experience, as well as our anticipation of the future, into some sort of larger context, and our visual system, literally how we are viewing the world at that moment, dictates how we create perspective in terms of states of mind. Sounds a little bit abstract, but actually, it boils right down to optics of the eye and very concrete things, like how you move your eyes and how you view the world.

Tim Ferriss: This is super fascinating to me because I’ve thought a lot about breathing and how, on one hand, breathing is a function of the autonomous nervous systems. When you’re asleep, you don’t have to consciously inhale and exhale. But simultaneously it’s this almost API into your autonomic nervous system, because while you’re awake, you can control and direct and modify your breathing for that directionality. But I’ve never thought about it from the visual perspective.

And just a quick bit of trivia that is out of left field, but nonetheless came to me that people might find interesting, is that the dilation, or this hyper dilation of pupils is — I don’t know how much it is associated with arousal or sexual arousal, but for those who’ve ever heard the word belladonna, it is a plant. And the reason it’s called belladonna, beautiful woman in Italian, is that it used to be turned into a tincture. And it is a psychotropic, and it is also very dangerous. I don’t recommend people consume it. But many, many years ago, hundreds of years ago, women in certain parts of Europe would create a tincture and put it into their eyes to hyper dilate their pupils because it was thought to be very, very attractive. Hence, beautiful woman.

Could you speak to how one can think about using their visual apparatus, or stimulating or not stimulating their eyes, their visual system, for, say, sleep. If one wants to optimize for sleep, what are some considerations? And it could be that it could be other inputs, but I’d just be curious to know how this fits into sleep for you, personally.

Andrew Huberman: Our light-viewing behavior has perhaps the strongest effect on our levels of alertness and our capacity to fall asleep and get a good night’s sleep. And this is because, at the fundamental layer of our biology, every cell in our body needs information about time of day. It’s no coincidence that we have a collection of neurons over the roof of our mouth. The so-called suprachiasmatic nucleus. That’s our central circadian clock. It informs every cell in our body about time of day. But it is deep in our brain. It has no access to light. So there are a collection of neurons in the eye, the so-called melanopsin ganglion cells, or sometimes called intrinsically photosensitive ganglion cells. These are just neurons in the back of your eye. Remembering of course, that the eye is actually part of the brain that’s outside the skull. And those neurons communicate to the central clock when it’s daytime and when it’s night.

So the simple behavior that I do believe everybody should adopt, including many blind people, we’ve talked about why that is, is to view, ideally, sunlight for two to 10 minutes every morning upon waking. So when you get up in the morning, you really want to get bright light into your eyes because it does two things. First of all, it triggers the timed release of cortisol, a healthy level of cortisol into your system, which acts as a wake-up signal and will promote wakefulness and the ability to focus throughout the day. It also starts a timer for the onset of melatonin, this sleepiness hormone, or the hormone of darkness, as they say. Melatonin is inhibited by light. So by viewing light first thing in the day, you set in motion these two timers — one for wakefulness that starts immediately and one for sleepiness that starts later.

The key thing here is that people are hearing a lot nowadays about avoiding blue light. Blue light is so terrible. Well, it turns out that blue light is exactly the wavelength of light that triggers activation of these cells. And that’s exactly what you want early in the day. So people generally will say, “Well, maybe I should just look at my computer or my phone first thing in the day.” Well, it turns out that these cells are very hard to activate early in the day and very easy to activate at night. So it’s kind of like the biology is encouraging us, if you will, to take on the right behaviors, which are to get outside. Even if there’s cloud cover, there’s a lot more light energy, a lot more photons coming through cloud cover then you’re going to get off your phone or a computer. And early in the day, two to 10 minutes outside without sunglasses is going to be really beneficial for a huge range of biological functions and brain state.

Tim Ferriss: I have made a practice, I’m in the middle of nowhere in the country right now, of getting up and not necessarily doing a full workout, but just jumping rope for literally like two to five minutes, two to 10 minutes, outside, facing the sun, when the sun is rising.

Andrew Huberman: Perfect.

Tim Ferriss: And there’s surely an effect. I am moving, so there’s an effect on cortisol. And as you noted, cortisol gets this ridiculously bad rap across the board. And it’s like, guys, if you don’t have cortisol, you’re dead.

Andrew Huberman: Exactly.

Tim Ferriss: If you like storing glycogen and breaking it down into glucose and so on, it’s important to have some cortisol. There’s a tremendous, for me, mood-elevating effect of this exposure. And I really have never familiarized myself with the mechanism by which that would be the case. And certainly, if it’s placebo, I’m happy to just take placebo. But do you have any explanation for why that exposure can have such a mood-elevating effect?

Andrew Huberman: Yeah. It’s definitely not placebo. That morning light exposure is going to also trigger the activation of dopamine release, dopamine being this, essentially, feelgood neuromodulator. The best way to conceptualize dopamine is that, yes, it’s part of the reward system, but it’s really the molecule of motivation and of positive anticipation. That’s really what it’s about. And I should mention that cortisol is going to be released in a pulse once every 24 hours, no matter what. That’s coming. It’s, as we call it, an intrinsic rhythm. But you can time it by viewing light and/or by getting exercise early in the day.

There are actually data, to just kind of emphasize what happens when you don’t do this, there are really nice data from my colleague, David Spiegel’s lab. He actually co-published this with the great Bob Sapolsky a few years ago. David’s our associate chair of psychiatry at Stanford. And they showed that if that cortisol pulse shows up later in the day, and especially if it’s around 8:00 or 9:00 p.m., then it’s associated with depression. By shifting that cortisol pulse earlier in the day, you ameliorate some of the symptoms of depression. And because of the dopamine release, you get this overall mood enhancement.

There are four things that really time our circadian biology and these mood mechanisms properly, and align us for sleep. And the most powerful timekeeper, as they say, zeitgeber, because Germans discovered this mechanism initially. So the most powerful timekeeper. Whereas — 

Tim Ferriss: Zeitgeber. Time giver.

Andrew Huberman: There it is. I knew you did better than I would. Is light. When you view light, and light is the most powerful stimulus for your biology and central circadian clock. Then it’s exercise. So it’s your protocol of jumping rope facing the sun. You’re layering on timekeepers. You’re giving more signals to the central clock and the rest of your body about when to be active. And you’re also indirectly signaling when you want to be asleep later.

Then, it’s feeding. I know a lot of people fast through the early part of the day now. That’s very fashionable and I do that as well, but were you to eat early in the day, that can also help. And then the other one is social cues. So interacting with people early in the day, or with your dog early in the day. I have a dog. I live alone with my dog. So that’s how I interact with the world socially. But those things are going to create wake-up signals and your body will start to anticipate them, and your brain will start to anticipate them such that if you miss it for a day, you’re still going to wake up and feel that alertness signal early in the day. So this is not something that you have to do every day, but ideally, you do it every day, because it’s like setting a clock or a watch properly.

And I should mention that for people that live in areas with very dense cloud cover, you can use lightboxes and things of that sort. But irrespective of that, in the morning and during the day in any time you want to be alert, you want to flip on as many overhead lights as possible. This is because these cells in the eye that trigger activation and alertness of the rest of the brain and nervous system reside in the lower portion of the eye. They view the upper visual field.

Now the inverse of all this is also important. As you approach the evening or nighttime and you want to go to sleep, that is a time to start avoiding bright lights of any color, not just blue light, and if possible, to place whatever lights are present in your environment lower in your visual field. So this would be desk lamps. Most people don’t have floor lighting. Dim the lights. If you want to wear blue blockers or do something of that sort, that’s fine. But I think people have taken the blue blocker thing a little too far by wearing them all day. That’s actually going to disrupt your circadian clocks. So in the evening, you really want to avoid bright light of any kind.

And again, it’s an averaging. If you do this every once in a while, you go to the bathroom in middle of the night, or you have an emergency and things are really bright for one night, it’s not going to screw you up. However, there was a paper published in the journal Cell a few years ago by my good friend and colleague at the National Institutes of Mental Health. His name is Samer Hattar. He’s the head of the chronobiology unit at the National Institutes of Mental Health. And what Samer’s lab showed is that bright light exposure of any wavelength between the hours of about 11:00 p.m. and 4:00 a.m. causes a serious disruption in the dopamine system, such that in subsequent days, you have a disruption in a lowering of mood, difficulty in learning. There’s a cascade of things that happen. In other words, we get punished for light viewing at the wrong times of the circadian cycle, and we get rewarded for light viewing at the correct times of the circadian cycle.

Tim Ferriss: Let’s let’s talk about the latter portion of the day. Before I get to that, though, just for my understanding. If one, say, wants to target, going to bed, or more accurately, feeling sleepy enough to go to bed easily with rapid onset at say 10:00 p.m., is there a preferred time to get that exposure? Early in the day? In the sense that if I’m doing my 10 minutes of jumping rope facing the sun, is it best to have it a certain distance, temporarily, from when I want to go to sleep?

Andrew Huberman: Yes. It’s about 14 to 16 hours prior to when you want to sleep is the ideal time to get that morning light exposure. And if we want to get a little bit technical about this, we can, and I’ll do my best to make it clear, because there’s also a way that you can use this mechanism to shift your circadian clock if you are to avoid jet lag and shift work. So I’ll just do this as a — I’ll just ask you. So what’s your typical wake-up time? Not getting up in the middle of the night and using the restroom, necessarily, and then going back to sleep. But when you finally get up and get out of bed? What time is that, typically?

Tim Ferriss: I would say when I’m living my best life and not being Marty from Back to the Future, it’s usually seven o’clock, let’s just say.

Andrew Huberman: Okay. So if seven o’clock is your average wake-up time, then we can be pretty sure that two hours prior to your natural wake-up time is what’s called your temperature minimum. It’s when your body temperature was lowest. That temperature minimum, and I should be clear, we don’t need to know your actual temperature. No one needs to know their actual temperature minimum. But you can count on the fact that two hours before waking up, your body temperature is close to or at its lowest point.

Tim Ferriss: And to be clear, this would be if you are waking without an alarm clock, right?

Andrew Huberman: Correct.

Tim Ferriss: That would be if you’re following natural rhythms.

Andrew Huberman: Correct. So if you view light, and I should mention, you have to do this with your eyes. And that might seem obvious, but some years ago there was a paper published in the journal Science, which is one of the three apex journals, Science, Nature, Cell. And it stated that light presented to the back of the knee of humans could shift their circadian clocks. And that paper was retracted by the same authors that published the study. There was a technical flaw. Humans have no extraocular photoreception. So we need to tell the cells of the body what time of day it is, essentially where we are in time, by light viewing behavior with the eyes. Blind people do this a little bit differently. Some blind people actually still retain these so-called melanopsin cells. People without eyes at all, maybe from a burn victim or something, they are going to use social cues and exercise and other things. But most everybody on the planet does this through light viewing behavior.

So when I say get light, what I mean is get light in your eyes. Obviously never so bright that it’s going to damage your eyes. You’ll know if a light’s too bright because you’ll want to close your eyelids. So that’s a simple rule of thumb. But the key thing here is that if you view light, in particular, bright light, in the hour or two before that temperature minimum. So for you, Tim, that would be between around 3:00 a.m. or 4:00 a.m., it’s going to have the quality of delaying your circadian clock. What it’ll effectively do is make you want to stay awake later and it will make you want to sleep in later the following nights. However, if you view light in the hour or so immediately after that so-called temperature minimum, so this, for you, this would be 6:00 a.m. or 7:00 a.m., it’s going to shift your clock in the other direction. You’re going to want to go to bed a little bit earlier, and you’re going to want to wake up a little bit earlier the next night.

Now if you hear this, you’re probably thinking, well, my clock is always more or less in the same place. How come it doesn’t jump around? I wake up. I view light. How come I’m not going to bed earlier and earlier every night, and waking up earlier and earlier? The reason is there’s a second time of day, which is in the evening as the sun sets, where your circadian clock is also vulnerable again to these shifts. And typically, because most of us are viewing light in the late afternoon, all of us are naturally having our clock shifted so that we want to get up earlier and go to bed earlier the next night and morning. But we’re also delaying our clock a little bit in the afternoon.

Now we can make this all very simple. The simple thing to do is within 30 minutes of waking up, get bright light exposure in your eyes, and not from a phone or from a screen because it won’t be sufficiently bright. Get it from sunlight. And if you can’t get it from sunlight, you can use one of these light pads. I don’t use one of these expensive wake-up clocks or something like that. I bought an LED drawing pad. It’s like a trace table. It’s like the artist’s cheat mechanism. And it actually says on it, I forget the company, but it says 930 lux. You can find these very inexpensively online, and that’s going to work great. I just set it at my desk in the morning if it’s very overcast, and I’ll work.

Now it is important to get outside because, even though your windows or the windshield of your car is optically clear, it filters out a lot of that blue light that’s important for setting your circadian clock. So two to 10 minutes of light viewing early in the day. And then you can do yourself a great favor as well by going outside in the evening or late afternoon as the sun is approaching this, what we call low solar angle, because that will also send another signal to the brain that it’s evening. So there’s a morning stimulus and an evening stimulus. This only takes a few minutes each day.

And what’s key to understand is that the cells of your body, they’re going to have all these rhythms of liver function and metabolic function, your brain is going to have its rhythms of alertness and anxiety and sleepiness, providing multiple signals. So for you, exercise and light in the morning, and then in the afternoon, a little bit of light, is going to tell your system in a redundant way, but in a powerful way, these are the times to be awake. These are the times to be asleep. And then if you like, we can talk about evening behavior.

But that temperature minimum is worth knowing because if ever you are traveling, for instance, to Europe, what you can do is, in the two or three days before, you can just set your alarm, wake up around your temperature minimum, maybe an hour before, turn on some bright lights in your home, so you get bright light exposure, and you will start to shift your clock forward. That nine-hour jump can be accomplished in about two days if you do this correctly. And the reverse is also true. You could shift your clock earlier, if you like.

And when you land in Europe, if we want to get him down into the weeds, when you land in Europe, you have to be cognizant of what your clock is back home. Remember your temperature minimum. It’s much more important than where you are in your new environment. That temperature minimum is an anchor point. Remember, light viewed in the hour or two before that temperature minimum will make you want to go to sleep later and wake up later. Light viewed after that temperature minimum will make you want to go to sleep earlier, and wake up earlier.

Tim Ferriss: Let’s talk about something that is a perennial topic, and that is sleep aids. Specifically, I’d love to get your opinion on various supplements, or prescription medications, for that matter, that people might use. Right? So there’s a huge list of things that people could use. On the prescription side, certainly, you’ve got the Ambiens and the Trazodones and so on. Then on the supplemental side, you’ve got melatonin. Very, very popular. You have California poppy. I mean, there’s an infinitely long list of various supplements.

I would love to hear your thoughts on at least two of these. One is melatonin, because of its popularity. And then the second is actually phosphatidylserine — so PS for short — and using it to blunt cortisol release after going to bed. I would just be curious to know if you have any opinions on those, or any others that you would advise against or advocate for or use personally.

Andrew Huberman: Sure. I’ll say why I’m not a fan of melatonin. When I was a graduate student, I worked on the melatonin system in the circadian system. And one of the most powerful effects of melatonin is to suppress puberty. The melatonin system is closely linked up with GABA inhibitory neurons in the hypothalamus. It effectively keeps puberty from happening. So the melatonin rhythms of young children, pre-pubertal children, are not as phasic, right? They’re pretty constant. And that’s one of the reasons they don’t go into puberty. There are many other reasons they don’t go into puberty until certain triggers are set. But melatonin has strong effects on the sex steroid hormones, the pathways related to estrogen and testosterone.

And I think it was the one experiment that I did where we took — we were working on these little, they’re called Siberian hamsters, these little hamsters, who in long days, because they are seasonally breeding animals, in long days, these Siberian hamsters have testicles, well, that at least for Siberian hamsters, are a pretty impressive size. If however, you inject those animals with melatonin, or you put them into short days, so you increase the amount of darkness and you decrease the amount of light, remembering, of course, that light inhibits melatonin, their testicles shrink to the size of a grain of rice.

So I don’t know if this was my male ego or something, but I saw that experiment and I thought, “Wow, this is powerful stuff. This melatonin stuff.” And it turns out in females of the same species, they leave estrous, they stop cycling. They don’t have menstrual cycles, they have estrous cycles. And there are powerful effects of melatonin on the reproductive axis. Now, humans are not seasonal breeders, and we have a more robust sex steroid hormone axis than that. But, especially for children, but also for adults, it just seems to me that melatonin has a number of other effects that are worth considering, enough effects that I tend to avoid it.

Now, I should also say that most of the concentrations of melatonin that are in supplements are 10 to 1,000 times what the endogenous internal levels would naturally be. So people taking melatonin are seeing dramatic effects, but you’re taking super physiological levels of melatonin. We all kind of balk when we hear about people taking a thousand milligrams of testosterone cypionate a week, which, unfortunately, certain people do. But this is the equivalent of super-dosing sleep hormones. And these are hormones that have other issues, and other roles, I should say, in the body. So that’s why I veer away from melatonin.

Also, there are three things that I personally have found to be much more beneficial that seem to have very good safety margins. Of course, everyone needs to check with their physician. But those three things are magnesium threonate, T-H-R-E-O-N-A-T-E, or bi glycinate, magnesium bi glycinate. Magnesium threonate and magnesium bi glycinate are able to be transported across the blood-brain barrier more readily than other forms of magnesium. I know you know a lot about this topic, Tim, so correct me anywhere I might misspeak.

But like for instance, magnesium citrate is a great laxative. It goes by another name, too, you can imagine what it might be, that will remind you that it’s a great laxative. It’s not great at inducing sleep. Magnesium threonate, or magnesium bi glycinate, so 200 to 400 milligrams, about 30 minutes before sleep, is a powerful sleep aid. People with heart issues might not want to take it or might want to check with their doctor. But I take a cocktail of magnesium threonate and then two other things. One is very commonly known, which is theanine, T-H-E-A-N-I-N-E, 200 to 400 milligrams of theanine can create a kind of a hypnotic state, help you fall asleep. Basically falling asleep requires turning off your thoughts. And the only people that should really avoid theanine, I think, are people who suffer from sleepwalking or night terrors. It can create very vivid dreams.

And then the third thing is apigenin, A-P-I-G-E-N-I-N, which is a derivative of camomile, but it acts as a chloride channel agonist. So it essentially helps shut down the forebrain by hyper-polarizing neurons and all this kind of stuff, for the aficionados, if they want to know. So that cocktail of 50 milligrams of apigenin, and 300 to 400 milligrams of magnesium threonate, or bi glycinate, and 200 to 400 milligrams of theanine, for me has been the best way to consistently fall asleep quickly and stay asleep most, if not the entire night, which for me is about seven, eight hours. And, of course, I’m not a physician, I’m a scientist. Everyone needs to figure out what’s right for them. But many, many people who I’ve recommended this to have told me that in combination with the morning light viewing, that their sleep has been completely transformed. They thought they were so-called “insomniacs,” but they actually were just having a hard time turning off their thoughts and probably their cortisol was drifting too late in the day.

Tim Ferriss: So to that cortisol point — this is fascinating, and I just find it endlessly interesting that different forms of magnesium can be so target-specific with respect to different tissues in the body. So, so fascinating. With respect to cortisol, and needless to say, I have used phosphatidylserine before sleep to help blunt cortisol release, but I do cycle. I use it as needed, really, if there’s a lot of rumination or I’ve had a particularly stressful day. But do you have any thoughts on whether or not you would ever do that personally, or if you’d be too concerned about side effects or long-term side effects? I suppose that could be a larger issue if you’re just never cycling off. But do you have any thoughts on using different compounds to blunt cortisol release if you’re over-ruminating and want to sort of minimize that, in this case, stress response while you’re trying to sleep?

Andrew Huberman: Yeah, it’s a really good question. I have not tried PS. I use ashwagandha from time to time if I’m in a particularly long bout of stress. One of the things that I think is relevant here is that we hear about stress as terrible, but, of course, short-term stress buffers the immune system. It actually activates the spleen to release killer cells and things of that sort. We are more robust in fighting off infection in the short term from pulses in cortisol. But I would say we can define long-term stress as if you are having sleep disruption or you’re feeling like you’re in that wired and tired mode, we don’t really have a technical name for this, for more than two or three days, you’re starting to enter the realm of long-term stress.

And that’s where buffering cortisol can really help. And that’s where I start to take some ashwagandha late in the day. There’s good evidence that can buffer cortisol. I do cycle it, so I’m not going to take it every night or every day. I would probably stop after a week or so, and then just go back to my normal regimen, which doesn’t include ashwagandha. But I always have some on hand. I have to say that I certainly use and enjoy the benefits of supplements. Many of them, in fact. But the practice that, for me, has really helped reduce stress and allowed me to fall asleep more easily and control my state of mind late in the evening is this practice that some people call yoga nidra, which literally means yoga sleep. And that practice of taking 20 or 30 minutes a day, and it doesn’t have to be done every day, and lying down and doing a sort of body scan.

It involves some long exhale breathing, which is very relaxing to the nervous system, and really allowing the mind to enter one of these pseudo-sleep states. We know from work in my laboratory and work that I’m doing with David Spiegel’s laboratory, as well as work from other labs, that that state of shallow nap or shallow sleep done in waking allows the brain and the person to get better at turning off their thoughts and falling asleep in the evening. So I use both behavioral tools and pharmacology, which of course is really what supplementation is, but I don’t have any problem with buffering cortisol a little bit in the short-term, so doing that for a week or two. But I wouldn’t suggest that people suppress their cortisol long-term unless there’s a real clinical need to do that. “Long-term” being longer than two weeks.

Tim Ferriss: Mm-hmm (affirmative). You mentioned long exhales in the context of the yoga nidra practice. Is it fair to refer to that yoga nidra practice as also non-sleep deep rest, or NSDR, or are those separate phenomenon?

Andrew Huberman: Yeah, so yoga nidra is one of several what we call NSDR, non-sleep deep rest protocols. Admittedly, I coined the term “NSDR” because scientists like acronyms, almost as much as the military likes acronyms. And I did it deliberately not to rob the beautiful history and community that is yoga nidra and the yoga communities of anything, but rather because many people are averse to doing anything that has a name like “yoga nidra,” and yet it’s such a powerful tool. It’s a zero-cost tool that has enormous effects on not just accessing sleep and calm, but enhancing rates of neuroplasticity. Something that we could talk more about. Also, David Spiegel, again, our Associate Chair of Psychiatry at Stanford and close collaborator and friend of mine, is a world expert in clinical hypnosis. Just in full disclosure, we both sit on the advisory board of a company called Reveri, R-E-V-E-R-I dot com.

Reveri is a zero-cost app on Android and Apple that has short hypnosis protocols. Anywhere from 10 minutes to 15 minutes. Hypnosis and yoga nidra both fall under the umbrella of NSDR, non-sleep deep rest. And these are protocols that people can use to deliberately access states of deep rest for sake of, again, falling asleep more easily, reducing stress, but also for enhancing rates of learning, of neuroplasticity. And because these are zero-cost tools, and because they are grounded in excellent peer-reviewed research, I feel comfortable mentioning them. And what you find is that if people who are not familiar with meditation or mindfulness, or maybe they’re not from West L.A. or the Bay Area, if they hear “yoga nidra,” they think magic carpets, and they hear “hypnosis” and they think that somebody is going to control their brain.

NSDR is my attempt to create a more friendly language, which is because all of these things are really just the same thing. They really involve two things: (1) self-directing a state of calm. That’s something that we never learn how to do unless we have a need to do it. We suffer some trauma. We have chronic stress. We start taking a mindfulness class. Self-inducing a state of calm through respiration and vision is the hallmark of yoga nidra and hypnosis, and frankly, of all meditative practices. Our thoughts follow our vision and breathing, and I can explain why that is in a moment. In addition, these NSDR-type practices involve not just self-directing calm, but they also involve directing our focus to something. We generally have a hard time falling asleep because we think we have to turn off our thoughts completely like a switch.

But the transition to sleep involves allowing our thoughts to become fragmented, and then we become relaxed, and then the brain enters the state where space and time are very fluid and not under our conscious control. And those are things that we can teach ourselves. So yoga nidra scripts are found all over YouTube. There are some great apps out there. The zero-cost ones that I use are — any of the stuff by Kamini, K-A-M-I-N-I, Desai, D-E-S-A-I, I like her voice very much. Some people, like my sister, loves Liam Gillen’s voice, another zero-cost yoga nidra tool. Liam Gillen. A double-L. G-I-L-L-E-N. So you have to find a voice that you like. The Reveri app is David’s voice, and he has a very hypnotic voice, and there are scripts in there for smoking cessation, stress and anxiety, sleep, et cetera.

These, I really want to emphasize, in addition to being zero-cost, are very powerful tools if done regularly. There are two papers that were published in the last two years from Cell Reports and Cell Press Journal, excellent journal, showing that a 20-minute non-sleep deep rest protocol after a bout of intense focus or intense attempt to learn anything, skill learning or cognitive learning, accelerates plasticity by about 50 percent. So essentially you are learning faster, much faster, and retention of that information lasts much longer. And that’s because these are sleep-like states, and we know that neuroplasticity, the brain’s ability to change in response to experience, is triggered by high focus, by deliberate periods of very high focus. But the actual rewiring of neurons, the formation of new synapses, and the reordering of the circuitry that leads to that skill or that cognitive ability becoming reflexive, that happens in states of deep rest, and non-sleep deep rest, NSDR, whether it’s hypnosis or yoga nidra or a shallow nap of about 20-30 minutes, those things will all accelerate learning.

Tim Ferriss: Let’s hop around just a little bit. Yoga nidra first on the NSDR study that you mentioned on the increase in plasticity, which I’m assuming it was measured by retention, recall, et cetera, but perhaps it wasn’t, if you could send afterwards a link to that study, I’ll put it in the show notes for listeners who might be interested.

Andrew Huberman: Sure.

Tim Ferriss: We’ve touched on breathing in a few different capacities. I have a term in front of me that seems kind of self-explanatory, but I don’t know what form it takes. Physiological sighs contrasted with other breathing methods for stress reduction. Could you define what that is?

Andrew Huberman: Yeah. A few years ago, when my laboratory got interested in studying stress in humans, we asked ourselves what are the patterns of breathing that allow for the most rapid reduction in stress levels? And more importantly, what are the patterns of breathing that can be done in real-time so that people can adjust their stress while they’re still engaging in life? Right? Breathwork classes, running off to SLN for a weekend is a magical experience, but if you’ve got life demands pressing on you, that’s typically when you feel stressed. So it is still true that vacation, long meditation retreats, and massages, or a good, nice drink if you’re of drinking age, still work, but they’re slow and they take you offline. The physiological sigh is a pattern of breathing that was actually discovered by physiologists in the ’30s, and that was essentially rediscovered by professor Jack Feldman at UCLA, a world expert in the neurobiology of respiration, and by my colleague, Mark Krasnow at Stanford, who studies lung function.

The physiological sigh is a pattern of breathing that we all engage in in deep sleep. When levels of carbon dioxide in our bloodstream get too high, we, or our dogs, you can see your dog do this, will do a double-inhale, followed by an extended exhale. Children, or adults for that matter, that are sobbing and lose their breath, so to speak, will also do a double-inhale, exhale. That’s the spontaneous execution of what we call the physiological sigh. The reason it works so well to relax us is because it offloads a lot of carbon dioxide all at once, and the way it works is the following: Our lungs are not just two big bags of air. We have all these little millions of sacks of air, that if we were to lay them out flat, they would be as big as about a tennis court or so. The volume of air, therefore, and the volume of carbon dioxide that we can offload is tremendously high, except that we get stressed as carbon dioxide builds up in our bloodstream, and, it’s kind of a double whammy, these little sacks deflate.

Now, when we do a double-inhale, so I’ll do this now twice through my nose, or you could do this. You could do it through your mouth, but it works best through the nose. It’s inhale, and then you sneak a little bit more air in at the very end. When you do that, you reinflate those little sacks, and when you exhale, then you discard all the carbon oxide at once. So the simple way to describe this protocol is that, unless you are underwater, you do a double-inhale, followed by an extended exhale, and you offload the maximum amount of carbon dioxide. And we found in our laboratory, and other laboratories have found, that just one, two, or three of those physiological sighs brings your level of stress down very, very fast. And it’s a tool that you can use any time.

And I do hope that people will kind of watch other people, or dogs, as they start to relax or go down to sleep, you’ll see this pattern of breathing. But again, it can be consciously driven. The other thing about breathing and the reason why exhales are so vital is the following: I know there’s a lot of interest nowadays in heart rate variability. Well, most people don’t realize this, but your breathing is actually driving heart rate variability. So when you inhale, this dome-shaped muscle beneath your lungs, your diaphragm, actually moves down. Because the lungs expand, it moves down. When you do that, you create more space in the thoracic cavity and the heart gets a little bigger. It actually expands. As a consequence, blood flows more slowly through that larger volume, and the brain quickly sends a signal down to the heart to speed the heart up.

The short, simple version of this is: inhales speed the heart up. When you exhale, the opposite is true. That dome-shaped muscle, the diaphragm, moves up. The space in your thoracic cavity gets a little bit smaller. The heart gets a little bit smaller. Blood moves more quickly through that small volume, and the brain sends a signal to the heart to slow the heart down. Physicians know this as respiratory sinus arrhythmia, but this is the basis of what we call HRV: heart rate variability. And the simple way to remember this is: any time you emphasize exhales, in other words, making them longer than your inhales, you are slowing the heart rate down. You’re calming your system. Anytime you emphasize inhales, you make them more vigorous or longer than your exhales, you’re speeding up your heart.

Tim Ferriss: I’d like to come back to hypnosis for a second. I’ve never been hypnotized nor — well, maybe I have self-hypnotized and just not realized that’s what I was doing. What characterizes hypnosis, or how would we define that? And do the states induced by hypnosis have any shared characteristics with some of the states induced by any psychedelics?

Andrew Huberman: So hypnosis is a state of calm and high focus. So context is restricted. It’s like looking at something through a telephoto lens. You’re eliminating the surround. So it’s a state of high focus, which normally, as we talked about earlier with the aperture of the visual system, would be associated with a high degree of excitement or stress. But hypnosis is a unique state, because you have a high degree of focus, but you’re very relaxed. And just to remind people that neuroplasticity is triggered by states of high focus, followed by periods of relaxation later in deep sleep or in non-sleep deep rest. In hypnosis, it brings both those states together at the same time. And this is one of the reasons it’s effective in accelerating neuroplasticity. I could probably do it right now to see if how hypnotizable you are.

There’s actually a test, a clinical test, called the Spiegel Eye-Roll Test. Spiegel’s father was a hypnotist and a psychiatrist. I want to be clear. These are not stage hypnotists. These are board-certified MDs and PhDs. There’s a lot of scientific research to support what we’re about to talk about. So typically, when we get sleepy, when we’re relaxed, our eyelids close and our eyes go down and the chin goes down. The induction to hypnosis involves doing the opposite, looking up, which actually, believe it or not, creates a state of alertness, and then having you close your eyes. So it creates a kind of conflict in the cranial nerves that innervate the eye and eyelid muscles. Again, the eyes and your state of mind are so intricately wired back there in the brainstem. So if you could look up toward the ceiling, Tim, with your eyes open, and then just while still maintaining upward gaze, if you could just slowly close your eyelids. Oh boy, you’re really hypnotizable.

Tim Ferriss: So what did you see? That was deeply uncomfortable.

Andrew Huberman: Yeah, I know. It’s a little bit odd. So for those of you listening or watching, you sort of look up towards what sometimes in yoga communities or in meditation communities they call the third eye center. We don’t actually have a third eye, but if we did, someone decided it would be between our two eyes on our forehead. So by looking up, you’re inducing alertness, and then you’re creating this conflict where I asked you to close your eyelids, which is what you do when you’re in a state of sleepiness. And what Spiegel, both Spiegel Sr. And Spiegel Jr., have figured out is that it’s a very good predictor of how hypnotizable people are. You can look up the Spiegel Eye-Roll Test. And what I was looking for is — let’s say if somebody is not very hypnotizable, what’ll happen is as they close their eyes, they’ll have a hard time closing them slowly. They’ll just kind of snap shut and their eyes will roll forward.

In other words, I’ll see their pupils again. What happened when I saw you do this, is that your eyelids were closing very slowly and I saw the whites of your eyes. Your eyes were starting to roll back into your head, so you would have a score of probably about a four, which is very hypnotizable. I’m about a four. Some people you’ll just notice. You say, “Look up and then slowly close your eyes,” and their eyes will just kind of snap shut and their eyes will roll forward right before it snaps shut. So you can do this experiment of sorts on people that you know, and it predicts pretty well how quickly or easily you will go into hypnosis. I should mention that no one will go into hypnosis if they don’t want to, but if you’re interested in exploring hypnosis with the Reveri app or with a clinical hypnotist and your eyes roll back the way that yours did, Tim, then you’re home free. You’re going to be long and gone.

Tim Ferriss: Amazing. Amazing. Maybe I’ll start speaking in tongues, too. It does have a good associated look with it. How would you explain the utility of hypnosis? And then I do want to hear if there are any sort of correlates to some of the known effects of psychedelics. And that’s a wide spectrum of class, so we could choose a given compound.

Andrew Huberman: Sure. Yeah.

Tim Ferriss: But what are the clinical applications? Because in my hypnosis-naive mind, I think, smoking cessation. Isn’t it good for quitting smoking? Isn’t it good for, really, just these anecdotal reports that I’ve read at one point or another? But what are some of the clinical applications or practical applications of hypnosis?

Andrew Huberman: Yeah, so for smoking cessation, if people do the practice, about a 60 percent to 80 percent success rate, depending on the study you look at. These were all blinded, controlled studies. In terms of anxiety relief, those are tremendously strong effects. As many as 90 percent of people are going to feel significant improvement in anxiety. For pain management, for chronic pain, there’s a high degree of success. So people will vary depending on how hypnotizable they are and how regular they are about the practice, but anywhere from 50 percent to 75 percent of people will experience a significant reduction in chronic pain. And if they are using pain meds, they tend to be able to take lower doses of pain medications in order to manage that pain. So it’s quite powerful.

Now, for trauma and things of that sort, it needs to be done with a, I would hope, board-certified MD, clinical hypnotist. And there, the success rates are quite high as well. And if you want more research about this, inside the Reveri app, there’s a long list of resources. I can send over a good review article that David’s written. These are, again, published in very fine quality, peer-reviewed journals of the New England Journal/JAMA sort and things like that. So in terms of similarity to psychedelics, they are quite distinct actually. So hypnosis being a state of high degree of focus and relaxation is a bit similar to some of the so-called “psychedelics.” So MDMA-assisted psychotherapy, which it appears thanks to the support and work of people like you and the MAPS group and the group at Hopkins — in particular Matthew Johnson.

And I realize there are other people in that mix, but I have to just say as a point, it’s really exciting to see what’s happening, and the enthusiasm about building safe protocols that people can access after so many years of people having to do this kind of renegade or in unregulated environments. MDMA creates a very atypical state. It’s a state of high dopamine release. Now, typically dopamine is associated with a focus on things external to us. Dopamine being a molecule associated with motivation and reward makes us want to do more of things that brought the dopamine, whether or not that’s food, sex, online viewing of any kind, et cetera. It’s not always bad.

Tim Ferriss: “Online viewing.”

Andrew Huberman: “Online viewing.” Whatever that is. The best way to describe the effects of dopamine are that it’s the — there’s a book actually, quite good book, called The Molecule of More, and that’s a great way to describe it. I wish I had written that book. I read the book and thought, “I wish I had written this book,” because I love the neuromodulator systems. And it is The Molecule of More. And actually anyone that thinks that dopamine is about pleasure, not motivation or seeking more, consider this. This is an anecdote I borrowed from my colleague, Anna Lembke, who’s in the Department of Psychiatry at Stanford. The next time you eat a piece of chocolate or you engage in a behavior that feels particularly delicious, notice the sensation and the thoughts in your mind. It’s rarely about complete presence and desire for staying present. It’s usually a desire for more. It’s this, “I want more of this, please,” as opposed to really basking in the experience.

And I should mention that Anna has a wonderful book coming out in August called Dopamine Nation. She was in The Social Dilemma, she’s an addiction therapist and psychiatrist, and talks a lot about the dopamine system. So dopamine makes us want more of whatever feels really good, and that tends to place us in an external focus. Serotonin, another feel-good molecule, is exact opposite. It tends to make us feel good with what we already have. It tends to be the incredible feelings of warmth that holding a child or a loved one or time with your dog — I have this bulldog Costello, and there’s times when I just sit with him and I feel immense pleasure just being there. I don’t think I want four bulldogs. In fact, I definitely don’t want four bulldogs. The snoring is loud enough already. But it’s about experiencing the here-and-now in a full and complete way.

MDMA is unique because it creates huge increases in dopamine and serotonin at the same time, and we don’t ordinarily see that in natural experience. And it has this unique property of making people feel very excited and positive about their relationship to their internal state. And so it has a kind of looping back of a mechanism that normally would place us in the viewing of the exterior. “What’s out there? What can I get more of? Who can I interact with more of? What drug can I take more of that’s going to make me feel this way?” So MDMA is very unique, and I mention it because it has certain correlates with hypnosis in that it’s a very focused state. In fact, so much so that, let’s just say, I could imagine that if you’re hearing music and you focus on that music, you can really kind of start to merge with the music. Whereas if you focus on your internal state, you can merge with your internal state.

And that’s why I do think it’s important that some of that, if people are doing in a clinical setting, be guided, because otherwise, the experience can be sort of lost on whatever is external. Other psychedelics of the sort like psilocybin and LSD, they have a very sleep-like state. They tend to be more serotonergic in nature, and they are very similar to sleep in the sense that space and time become very fluid. Whatever top-down governing mechanisms exist in the brain, so-called “executive function,” some of that seems to be dysregulated enough so that inside of those psychedelic states, and certainly inside of dreams, anything can really happen, and you can essentially see and appreciate novel associations that normally wouldn’t occur in waking states. We should remember that the two extremes of human experience are stress and/or excitement. So highly contracted visual window, highly contracted time domain, everything sliced very finely.

“What’s happening next? What’s going to happen next?” Think you’re in the line of the airport and the person in front of you is moving slowly and you’ve got a plane to catch. Everything constricted to right there, both in space and time. And then, sleep, where, in sleep, space and time are extremely fluid. Anything can happen and you are essentially out of control mentally. It’s just whatever is going to happen is going to happen. Psychedelics are very much like that, except that in LSD and psilocybin-assisted states, you’re alert. So I would say that psilocybin and LSD-like states are similar to hypnosis in that way, but hypnosis has a little bit more of a rigidity to it. It’s set toward a particular focus, like, “Let’s work on your control over stress or smoking or pain.” And so I would say the three of them occupy neighboring spaces, but none of them overlap completely.

Tim Ferriss: Yeah. I’d be so curious to see some type of multimodal study, and perhaps they’ve been done, but just looking at pharmacological interventions combined with hypnosis, right? So if we made hypnosis the default sort of control state, and then you add an arm that was comparing hypnosis plus fill-in-the-blank. Not necessarily psychedelics. Certainly, I mean, it could be an entactogen or an empathogen like MDMA, it could be a tryptamine like psilocybin, or it could be like a phenethylamine like mescaline, which has very different effects, certainly. I think Michael Pollan does a good job of describing this in his new book, Your Mind on Plants, in his entire section discussing the mescaline experience. Which is really, in a sense, an amplification of the real in high-resolution, certainly dose-dependent versus transportation à la the tryptamines like LSD or psilocybin. That’d be very, very interesting to see.

Andrew Huberman: It would. And I have to say, as usual, you’re five years or more ahead of everybody else, Tim. And I don’t say that for sake of flattery. I mean, you have a way of spotting the horizon. And I think we are so caught up as a culture now in asking, “What should we do? What should we take? What device should I use?” I always say: You’ve got behavioral tools. We all have to eat sooner or later. Nutrition, supplementation, prescription drugs, off-label and on-label, and then you got brain-machine interface devices for reading and writing to the nervous system and body, for measuring things and changing things. And we always think of those as separate bins, but as you were pointing out, I think the most interesting bin is to consider, well, maybe at some point, a learning bout is going to be 300 milligrams of alpha-GPC and a particular breathing protocol that will have a synergistic effect.

I think that’s where the real immediate future of beneficial brain change lies. And I think even the folks at Neuralink — a guy that came up through my lab, he’s a neurosurgeon, Matt McDougall, is at Neuralink now, and they have other excellent neuroscientists there. And you can be sure that they’re thinking clinical issues first. And they’re thinking, obviously, brain-machine interface and chips and robotics and things of that sort. But you can bet, just given who makes up that company roster, that they’re all probably also thinking about ways to accelerate plasticity using a combination of brain-machine interface and pharmacology. And if they’re not thinking about that, they definitely should. So I think for the typical person who’s not going to implant a chip beneath their skull, I think you’re hitting the nail on the head, which is that we need to think about what works independently and combining those for sake of synergy. That’s what’s going to get us where we need to go much faster.

Tim Ferriss: For sure. And I also think, just to build on what you said and thanks for the kind words, that when you look at these possible synergistic combinations, you could also end up, and this is not a certainty but it’s a possibility, having a much more appealing risk/benefit calculus in the sense that if you can lower the required dose of a pharmacological intervention, if you can lower the exposure necessary with some type of neurofeedback or neurostim, like a TMS or a tDCS or any of these other tools, if you’re able to lower the required doses of several things when they are used in combination and get a similar or better outcome, it just has such incredible ramifications for the clinical use of these things. Let’s take a step back here. So now, we’ve covered a bunch of the research. We’ve covered a bunch of the sort of tactical, practical implementations of some of the research findings. Now I want to paint a picture for people who don’t know you at all. So we’ve already covered Costello. We have not discussed the fact that you have, it looks like full-sleeve tattoos on both arms.

Andrew Huberman: You outed me. Yeah. You’re the first. This the first. Yep. It’s true.

Tim Ferriss: All right.

Andrew Huberman: They’re all birthmarks, of course.

Tim Ferriss: They’re all birthmarks.

Andrew Huberman: Kids, don’t start, because they’re like potato chips. Can’t get just one.

Tim Ferriss: And we may get to aquascaping. That’s a whole separate conversation. So we may get to that. But I want to rewind the clock for a second, because I read your bio. Obviously very impressive bio. You’ve received numerous awards. You’ve produced a lot of incredible work with your colleagues in your lab. Let’s go back to what happened to you in July of 1994?

Andrew Huberman: So in July of 1994, I was living in a little town called Isla Vista, which is near Santa Barbara. It’s the home of UC Santa Barbara, University of California Santa Barbara. Just as a little bit of background, I was not a good high school student. I had a very disrupted high school experience despite growing up in a good area. Just a lot of tension and stuff at home, so I barely finished high school. But I followed a high school girlfriend off to college. Somehow, I got in. At the time, I wanted to be a firefighter. Took fire science courses at Mission College in the South Bay, and I thought it’d be a firefighter.

And I put that in my entrance exam, and somehow, they let me in. But by the end of my freshman year of college, I had terrible marks. I had been thrown out of the dormitory living for getting in fights, something I’m certainly not proud of, and I was basically doing nothing. That summer, I was squatting. I was living in an empty house, because a lot of the houses were empty. I figured, “Why pay rent?” Living in an empty house with my pet ferret. And to sort of set the context right, I think I was still grappling with a lot of anger and resentment and confusion based on having rather confusing teenage years and a lot of disruption. Fortunately, I’ve formed a lot of friendships and formed a community in the skateboarding and punk rock culture. I was fortunate enough to get to know a lot of guys that have gone on to do great, like my friend, Karl Watson is Adidas Skateboarding. I spent some time and got to know, although we weren’t close friends with the great Danny Way, probably the great one of the greatest skateboarders of all time. Jumped the Great Wall of China. But I wasn’t a very good skateboarder. I was not a musician. I knew how to do essentially nothing well. And July 4th, 1994, I went to a barbecue with some friends and some guys were robbing the house that we having this party at. We came back from the store and we saw these guys essentially taking a bunch of possessions out of the house.

And the thing erupted into this big fight. This huge melee. I definitely went in excited to fight. I’d been involved in fights before, and I had an adrenaline-seeking thing. I felt like it was justified. I’m certainly not encouraging anybody else to do this, but essentially what happened was my friends took off. My so-called friends took off and I ended up in a fight with like four or five guys. Knives came out. Bottles. It’s the sort of thing where quickly you realize that things could go badly wrong. Fortunately, I stayed on two feet and nobody got badly hurt or killed. The police showed up. And actually, because of the fact that they were robbing us, they actually congratulated me. I’ll never forget, this is actually what made me feel worst of all. It was one of the police officers said like, “Nice work,” or something like that.

And I just realized that I was in serious trouble. I’m 19. I barely finished high school. I barely scraped through my first year of college. I’m living in a squat with my ferret. My girlfriend had left me. I didn’t do anything well. I didn’t know how to do anything well. And so that day, and I still have this letter, I actually sat down and I wrote a letter to myself and to my parents saying that I was going to turn things around. And I don’t know why I wrote to them, because at the time I was kind of avoiding contact with them entirely. I’ve since formed a really good relationship with both my parents. But I decided that day that I would use the one power that I seem to have, which is to remember facts and information. And what I did was I left Santa Barbara.

I took a leave of absence, went back, went to a local community college in the Bay Area. I did two quarters there and I just started studying like a maniac. First psychology, then biology. I eventually fell in love with neuroscience and related themes of endocrinology. And the rest is sort of history in terms of eventually going to graduate school and getting a PhD and becoming a professor, tenured, and all that stuff. But it was one of those moments where I realized I am no longer going to be a young screw-up. I’m going to be a 20-year-old screw-up. And with time, people are going to be less and less forgiving. And whatever had happened prior, no one’s going to care.

It doesn’t even really matter. And if I do want people to care and it’s not like I have a need to talk about the challenges early on, but I need to get my act together. I need to do something. I need to get good at something. And so I became a kind of a maniac. Actually, when I read your book, The 4-Hour Workweek and The 4-Hour Body, which I read and loved and own, I should say. Again, not for sake of flattery, but they really helped me. There are a lot of useful tools in there. There were certain things that resonated. I figured out that if I drank a lot of coffee and took certain supplements, I could focus for many hours. And then if I worked out, I built another capacity.

And if I ran, I built another capacity for endurance. And I started to explore the crossovers between — weightlifting is one thing. It’s not about building muscles or necessarily — maybe it’s about that. It’s about really moving against a physical force in real-time. And really learning how to do that. Endurance work is about learning how to push through a different kind of barrier and learning the carryover and crossover points. So I was the guy that would sit down at my desk. I moved, I decided to live alone in a studio apartment, and I would set a timer for several hours and I wouldn’t allow myself to get up.

I was allowed to listen to Rancid, best band ever for me, on repeat. And Bob Dylan. That’s all. I wouldn’t even allow myself to change music. And then I would just sit there and I would read my textbooks, underline my textbooks, write my textbooks. And I just decided I’m going to get straight A marks. I’m going to go to graduate school. I’m going to get a PhD. I should mention, there were people that came along at various times and helped me. Role models, mentors, people that spotted that. But it started with a switch that flipped on July 4th, 1994, and getting in a bad fight. And here I am.

Tim Ferriss: Deciding to choose a different path. So I want to underscore or explore a few things. And I really appreciate you sharing this because I think it’s very easy for people listening to folks with a bio like yours to sort of assume a certain trajectory, right? To assume that it has always come easy, and that you’ve always, since you were two years old, known exactly which direction you were heading, which is not the case. One clarification with UC Santa Barbara, because this might be an important point. It may might not. You did not drop out. You took a leave of absence. Is that right? Is that material to the story? Because I know in a lot of cases, there are folks who are kind of painted as dropouts, but in fact, they kept their options open by taking a leave of absence instead. So I just wanted to clarify.

Andrew Huberman: Yes. A leave of absence is a mechanism that most universities have. I think it was designed for things like family situations. If somebody gets pregnant or they have a family member who’s sick that allows you to leave and come back. And it’s distinctly different from dropping out. Although I was pretty close to dropping out, of being forced to drop out for reasons related to poor grades and poor behavior. Fortunately, that didn’t happen. I think it’s a really important point because we hear that Bill Gates dropped out of college, Steve Jobs dropped out of college, Mark Zuckerberg dropped out of college. I think maybe it was Ryan Holiday who, I don’t know, who said, something like, “The people who are doing poorly in college, they’re the ones that should stay in college because it’s the one environment where everything is scripted out for you, what you need to do in order to hit the next metric of success.”

And a leave of absence is very different. None of those people dropped out of college. They took leave of absences that gave them an insurance policy that they could go back if they wanted to. And it’s very hard to make it back into a system of any kind, but it certainly is much harder if you completely divorce yourself from that system. I am a believer in formal, rigorous coursework. I am a university professor. I know that college isn’t perfect for everybody. It might even be the wrong decision for certain people. But if you’re still uncertain about what you want to do, I think if it can be arranged financially and it’s in the scope of things that somebody might want to do, I think learning how to sit down in a chair and force yourself to learn and then compete with others in terms of how well you learn that information, I think is a great way to evaluate oneself early in life. And it sets the stage right.

Tim Ferriss: I agree with that. If you’re open to it, and certainly you can say no, or we can talk about it and then you can elect to have it edited out of the conversation. But you mentioned tension and stuff at home. Disruption. Are you open to sharing a bit more detail about what you mean when you say those things?

Andrew Huberman: Sure. So, I had a pretty magical childhood, really. My dad’s a scientist. My mom wrote children’s books and was a teacher. We ate dinner as a family, everybody together in the early part of my life. I acknowledge that I had great privilege in having that experience and growing up where I did. Good schools, good public schools. I completely acknowledge the benefits of that, especially early in life. Around 13, when I was 13, my parents split up. And either because of the time in which it happened or because they weren’t equipped with the right tools, there was a complete fracture of that picture. My dad was very much out of the picture at that time. My mom hit, I think, a series of challenges adjusting. I think it was what could only be described as a major depression.

I think her view of family was one in which everyone stuck together, no matter what. She’s from the East Coast. She’s from New Jersey. Like you stick together, it’s fine. We had an argument the other day, I don’t think she’ll mind me telling this, and we got on and we were ready to scrap. And we haven’t had one of those in years. But I just remembered that at the end of this conversation we’re going to be okay. And at the end we were closer. So we both have that. And I think, for her, the fact that there was a complete disintegration of the picture, my sister out of the house, my dad out of the house, and me there, she really hit the skids and home became a very empty, very quickly became a very empty and depressing place.

It was really — it was just really sad and I found care and love and community in the world of skateboarding. This was the early ’90s and there was this collection of mostly young guys at that time who would aggregate at Embarcadero Plaza, Justin Herman Plaza in San Francisco. I started going up there and hanging out at the — it’s now the famed EMB. It’s kind of got a golden era reputation now. And that’s where I learned that you don’t have to go to school. There are a lot of guys not going to school. There was a lot of drinking, a lot of drug use, a lot of wild behavior, but also I should say a lot of amazing skateboarding and amazing characters and personalities and fights and everything. It was true street life. And so I started staying there. I’d stay at people’s houses or sometimes we’d even sleep there.

And I learned a lot about how people outside the cozy suburbs of the South Bay, how they lived. And I’m grateful for that because it exposed me to the fact that many of these kids had no parental oversight from any age. That they had to scrap for everything. But quickly, I realized that I wasn’t very good at skateboarding. I didn’t have a future in it. And I wasn’t going to school. My home life was really disrupted and I lapsed into a pretty serious depression. I just remember, and anyone who’s experienced depression, I hope this will resonate with, although I’m sorry that it exists, but there’s this weird thing about depression, which is that it changes your actual view of the world. I remember leaving Embarcadero sometimes and looking up at the sky, back then they had the Embarcadero freeway, and thinking “The sky is so sad.”

Like not the sky as a separate object, but that this scene of this sunset is so sad. And actually yesterday I was thinking about this because there’s this beautiful sunset where I live. And I thought, “Gosh, I haven’t felt sad at the view of the natural world in so long” and so it was clearly a shift in my internal state. And fast forward, what happened was eventually the school picked up on the fact, my high school picked up on the fact, that I wasn’t going and they called me in at some point. I was sitting down with a school counselor and they had this guy in the room with me sitting there. And pretty soon I realized that I was in a different kind of situation. And I realized they were going to probably try and take me away because I was completely truant. I hadn’t gone to school. I was clearly depressed. So that’s what happened. Against my will and despite an attempt to run away, I was taken to a place up the peninsula which was neither a juvenile hall nor a psychiatric hospital, but we were under a lock and key.

And I was in there with kids that had dealt with everything from sexual abuse to hardcore substance abuse issues. And I’ll never forget this, they said, “The kids in the ward next door, they’re crazy because they’re really young and the adults in the ward on the other side, they’re crazy. But you guys, you’re not crazy.” And I thought, well, that’s ridiculous because they’re probably saying the same thing to the ones on the other side. But I had no one to call. I called my skateboard team manager, out of sympathy, not because I was any good. I’d got put on a wheel company, in a truck company for skateboarding. And I called the guy and I said, “I don’t know what to do. I’m in this place.” And he, I’ll never forget, he said, “I can barely take care of myself. And you’re the most normal guy I know.”

And I realized at that point, I’m like, “I’m really alone here.” So the long and short of it was, I did the work. I put my trust in the counselors that were there. They seemed like good people. And I did the work, but it’s part of an agreement for getting let back into school. Actually, it’s part of an agreement for being let out. I had to do weekly therapy and I was fortunate enough that I got placed working with somebody who understood my particular needs, worked with adolescents and really encouraged me to start exploring my mind. Certainly the situation I was in, but encouraged me to start meditating. He gave me Jon Kabat-Zinn’s book, Wherever You Go, There You Are. He saw how much physical energy I had and he encouraged me to start running.

I was always hurting myself skateboarding and he said, “Well, maybe running or swimming.” And running and swimming are amazing because unless you really do it wrong, you can go and go and go. It’s just I could burn off all that anger and energy over time. And then I started getting into weightlifting and weightlifting is kind of a double-edged sword, I should mention. I think it’s one of those things that is great, but if you exceed a certain size, it can actually make people kind of scared of you. Sort of like the tattoos thing. A lot of the reason why I cover up tattoos is because then people just see your tattoos. But it’s true. I started getting tattooed pretty young, the wrong way. Don’t do it this way, with India ink and a needle. This was before autoclaves. Bad, don’t do it.

But I decided at that age that the therapy and this one person who seemed to really care about my mental and physical well-being and would spend the time was really worth investing in. And I hid it from everybody because no one did therapy then, no one talked about it. It’s like late ’80s, early ’90s. Nobody did that. And, I will confess, I don’t think I’ve ever said this publicly, but I found a way either through insurance or through my own income, I’ve continued therapy with that same individual now for 32 years. And so I do, I confess, I do three sessions a week of psychoanalysis. Remote or in person. And I know people have a lot of, they do the other kind of eye-roll — not the Spiegel Eye-Roll Test, but the other kind of eye-roll — when you say psychoanalysis. I think an exploration of the mind is extremely powerful. It has to be done with the right person.

And there’s only one person I know who’s done this kind of extended work for so many years. And that’s the late Oliver Sacks, who’s a kind of a hero of mine — also worked with a psychoanalyst for many, many years. And so psychoanalysis, a fight on July 4th, 1994, a lot of attempts to both stabilize my mind and also organize my behavior. Those things go hand in hand, of course, but also biology to leverage — I guess you could call it biohacking or you call it — I just call it biology. I mean, when I learned, for instance, that I’m taking a thousand milligrams per day of EPA, essential fatty acids, not just fish oil, but getting above that threshold, is as effective as antidepressants. In double-blind, placebo-controlled studies, I mean, I’m not — this is — when I saw those papers, I realized, “Well, I probably have a bit of a leaning toward depression. I’m going to do that.”

Now did I do that and drop therapy? No, I do that in therapy and I train and I try and work on my sleep. It’s a constant process. But biology and the information contained in books like yours and hopefully, and the information that I’m trying to put out into the world now, that stuff helps in a major way too. So it was a multi-pronged support system and many incredible mentors along the way. But I was definitely at the edge. I know you’ve talked about this public too. I mean, there were times when I just thought, “Why continue?” And I’m fortunate, nowadays, I feel very far from that. There’s a saying in the world of addiction and addiction treatment, which is that “No matter how far you drive, you’re always the same distance from the ditch.” That, I would say, is true of addiction.

Fortunately, at least in my own experience, that is not true of depression. I have vowed to never go back to a place where living seems meaningless. And anyone who’s been close to that place, all I can say is, the work works. Whether or not it’s therapy, biology, et cetera, you have to do it. And there are things that can accelerate that process, but it’s an ongoing battle, to be honest.

Tim Ferriss: Well you’re fighting the good fight, man. And I’m certainly right in there with you. How does it feel to talk about this stuff?

Andrew Huberman: Yeah, it’s interesting. I always get a little quaky on this. I would say there are only two things that will always consistently make me cry and those are the thought of, I don’t even want to talk about for too long, because I prefer not to cry, but one would be when my bulldog, Costello, goes. We’re very bonded and he’s close, unfortunately, so he’s in his final years. And the other is when I think about my mentors, in particular, one, passing away. Talking about this gets me in a mode where it’s uncomfortable. I’m definitely uncomfortable at this moment. I’m okay to talk about it because I think these issues are important. And I wholeheartedly believe that many people struggle with them. I’m always conscious of protecting the people in my life who were doing the best they could with what they had.

So my parents are good people. That generation didn’t have the tools that I had access to and I do hope the next generation will have access to more tools. So I want to protect them. I’m blessed. I acknowledge my privilege. And I don’t say that for political reasons, by the way. I just want to say, I acknowledge that I was born into a pretty fortunate or very fortunate situation that provided buffers and I only know my own experience but I acknowledge it as real.

Tim Ferriss: Thanks for sharing all of that. And a mutual friend has prompted me to ask about the Hoffman Process.

Andrew Huberman: The Hoffman Process. So the Hoffman Process, it’s a personal development process. It’s a full immersion week-long process, I think it used to be two weeks. I don’t want to give away too much about it because if one were to go, you want to have the experience for the first time without expecting or knowing what’s coming. It involves a lot of both physical and kind of emotional purging. And what’s interesting is generally between 20 and 40 people go; you don’t publicly share any of the issues that you’re grappling with. There is a teacher there that you communicate with and who knows a lot about your situation. There’s a lot of work that you do beforehand, paperwork. So they really know closely what you’re grappling with. And you do get to know people there, but there are strict rules. No romantic relationships, no discussion of politics, no discussion of work, no discussion of sports.

And you quickly find that you realize A, that you spend a lot of time thinking about and talking about those things in the outside world and, B, that there are other ways to connect with people that are very authentic, that don’t involve those things. Hoffman Process was one of several things for me that was transformative. For me, it was most transformative in the realm of forgiveness. I felt completely resolved of my challenges with inability to focus, complete work structure, et cetera. I’d solved all that. I learned how to work hard, perform well by the time I went to Hoffman, which was in my early forties. I’m 45 now. I learned how to control my physical landscape as best as one could or should. I went there thinking like, “Why would I go here? What’s the purpose in going?” And yet I realized that I harbored a lot of resentment, mostly toward family members, but also toward experiences and people outside of my family.

And I almost got kicked out of Hoffman the first day, not for misbehavior, but because I slept through the first day. I’d been working so hard. They kept saying, “You’re trying to escape by sleeping.” And I’m like, “I’m just tired.” They take really good care of you there. I’ve actually never felt so nurtured. I’m not somebody who accepts nurturing very easily. I like to think I’m more of a caretaker and a more of a kind of caretaker loner type than being taken care of. And Hoffman, I felt comfortable to be taken care of in certain ways. And I discovered in doing the work that there were all these resentments and I was able to purge those resentments and I have to say, it completely erased all feelings that I was wronged by anybody or anything.

And that’s powerful and it’s completely behavioral nature. There’s no pharmacology there. I would say Hoffman is among the two or three things that — or maybe four or five things that were really transformative for me. And there is a price point, but they do have a scholarship program that’s been established, thanks to the generosity of various folks. So for people that can’t afford the price point, they do have a fairly simple scholarship program where you write something out. People who are practitioners, therapists, and in the wellness community, I think also get a break of some sort. I have no business relationship to Hoffman, but I’ve recommended that several people go and it is powerful and it does last.

In fact, the reason I decided to go to Hoffman was because somebody — actually, a mutual friend of ours, Tim, who I don’t think went, Wendy Yalom, who I know from way back when we haven’t been in touch in years. But I think she said something about Hoffman and she said she knew somebody who went and I contacted that person. And that person said, “I went to Hoffman and 10 years later, it still has a profound, positive effect on my life. And I found it to be more useful than any other kind of therapy or training of any kind.” That’s my Hoffman story and it’s powerful.

Tim Ferriss: Yeah. And for people who want to hear more about Hoffman, I talk about it at length also with Blake Mycoskie in the last conversation I had with him. So you can find that episode. You mentioned one of four or five things. What are some of the other things that have had a disproportionate, positive impact?

Andrew Huberman: This is a broad category, but get your biology right. Start with sleep. Figure it out. Figure out how to get your sleep right because it’s the fundamental layer of mental health. So get that one right. Other things in the biological category are learn how to focus, learn how to de-focus. Learn how to flip the switch on, learn how to flip the switch off. Get good at sleeping. Of course, exercise of various kinds is going to be good and all the other things, but there’s just that physical bin. And those are the primary levers there. I do think some form of exploration, whether or not it’s psychoanalysis, psychotherapy, journaling, or some sort of internal reflection that’s somewhat unregulated, but obviously not damaging to you or anyone else. So don’t punch concrete walls, but have the ability to sit down and data dump and reflect. If you can’t afford therapy, reflect on what you’re seeing and reading and feeling. Have the ability to experience what’s internal. So that will be the second one.

The third one is, and I realize there are some issues around legality and things and right now everything’s in transition, I was part of a clinical trial so I can safely say this. I do think that there are certain aspects to, let’s just call it what it is, either plant medicine, or — I was part of an MDMA-assisted psychotherapy trial. That was extremely valuable. There’s no question to me that that’s a powerful mover of one’s ability to feel comfortable in internal state. The way I would just briefly describe that experience for me is that I could feel perfectly fine from here to here and from the belly button down. But I had this feeling always that I couldn’t kind of experience things in mind and body at the same time. I know this is going to sound really wacko to people who maybe haven’t experienced this, but somehow in that brief experience, I was able to resolve that and I now experienced my nervous system as a complete entity.

And I do not think people should cowboy this stuff and do it on their own, or try and do therapy for their friends or do this on their own. I don’t think this is something that people should play around with. These are very powerful tools. You should do this with a board-certified MD. Sign up for a clinical trial. Hopefully, this will be done in these sorts of medical settings soon, legally, and you don’t have to be part of a clinical trial. But if you struggle on going in some way, I do think there’s utility there. So, that’s another bin. And then there’s another bin which, for me, has been very powerful, which is stay on the adventure. Continue to have fun. It’s so easy to forget to have fun when you’re doing all these other things.

Stay in the adventure and don’t get killed doing it. But really try and keep exploring. I do believe these dopamine systems are positively reinforced by novelty and exploration. We know that. And by venturing into new territories. And that requires getting certain things wrong. It means going to a retreat that sucks. It means taking a class that is not that interesting. It means finding out that a particular relationship is not right for you. But it’s important to stay in a mode of adventure because that’s fundamental to the human experience, and it’s fundamental to these neurochemical systems as well.

Tim Ferriss: A couple of points I’d love to underscore here. So the biological piece you’ve discussed in other places, this principle it’s a quote of sorts, a maxim that I think is really worth remembering. And I’m saying that to myself, as much to anyone listening that is, “You cannot control the mind with the mind.” And whether or not there might be exceptions to that, I think as a general rule through using the bi-directionality, as you’ve mentioned. A sort of body-mind, mind-body, and when in doubt working through your fuller biology is incredibly powerful. I mean, for me like to get out of my head, I need to get into my body. There’s just no sort of metacognitive way generally for me to otherwise do that. Or if there is, it’s just much more difficult. I’ve even told my girlfriend. I’m like, “If I’m trying to figure out what is bothering me and I spend more than like a half-hour on it, just tell me to go to the gym and lift heavy things for at least 30 minutes.”

Andrew Huberman: Best remedy in the world.

Tim Ferriss: And then I come out like, “Yeah, that bullshit’s fine. It doesn’t matter.” And that’s what was necessary. On the adventure side — actually, before I get to the adventure side, just a quick note on Costello because I think a lot about my dog Molly and mortality, and it’s just, it’s like so easy to get sad and — 

Andrew Huberman: How old is she?

Tim Ferriss: She’s seven, but she’s had some health issues. She’s had two spinal surgeries. And if you haven’t looked into the canine research with rapamycin, I would look into that. It’s very, very compelling. So that might be something — 

Andrew Huberman: I’ll do that. I listened to your podcast with Peter Attia and a lot of discussion about rapamycin. I’ll definitely check it out.

Tim Ferriss: Yeah. It’s worth checking out. There’s also a separate episode with David Sabatini of MIT, who is a genius and is sort of mTOR wizard —

Andrew Huberman: That family. He has a brother Bernardo Sabatini, he’s a famous neurobiologist at Harvard who I know quite well. And their dad, there’s another Sabatini who is at NYU Med. So those Sabatinis they’re kind of like the Kornbergs. Kornberg discovered RNA. His son discovered the structure of RNA. They both got Nobels and I think their brother is an immunologist or something like that. So if you’re thinking about changing your last name, Sabatini or Kornberg is a good one to select.

Tim Ferriss: Yeah. Not, not, not bad. Yeah. They come from the Secretariat stock of the scientific gene pool. On the adventure side, so you said “Don’t die,” or “Don’t let something kill you,” which I think is a perfect segue to, as I’m reading it from a paragraph from Outside magazine, “Huberman was about 40 miles off the coast of Mexico and 40 feet below the periwinkle surface of the ocean.” What does this refer to?

Andrew Huberman: Oh my, yeah. So before I went to Hoffman, I was still working out some things. So the quick backstory, this is in 2016, I decided I was going to shift a lot of my laboratory work toward humans. I understand the issues of animal research and why it’s important. My lab still does work on mice because there’s certain things you can only do on mice, but I want to work on humans. And I want to use virtual reality to induce fear in the laboratory and study stress and fear and other brain states. And we realized that VR, as it stood at the time, was just pretty lame. It was computer-generated images. It didn’t have 360 video or sound.

And so I got linked up with a guy named Michael Muller, M-U-L-L-E-R, who’s a very, very famous photographer in Hollywood mostly. Does all the Marvel stuff. He’s shot everybody. You just go to his website, it’s just — it’s kind of just a constant scroll of iconic images. Muller and I got to be friends and the reason I was excited about getting to know him is because a hobby of his is that he takes photos of great white sharks underwater. He brings these giant strobe lights underwater, and Muller is — you know you hear about the character of the Wolverine, Hugh Jackman, right? Muller is a Wolverine. He’s hunched over and he’s the nicest guy in the world, but it was like, it was immediate friendship, but he loves adventure. He’s got a family, kids, everything, but he loves adventure. And he said, this is my best Muller inter personation, he’s like, “Bro, you got to come down to Guadalupe, the sharks are there.” And I was like, “Well, what are we going to do?” And he’s like, “Well, we’ll just film them with 360 cameras.” And so, in 2016 we went down there and we filmed great white sharks as a stimulus for this fear laboratory that we were building and got 360 video. And the way we did that was that Muller and a couple other guys, these expert great white shark divers, would leave the cage. You lower the cage about 40 feet below and they leave the cage, they come back in — so it’s called cage exiting.

Definitely illegal to do. We got permits from the Mexican government because this was for a scientific study.

Tim Ferriss: I would have loved to see that permitting process. Anyway, continue.

Andrew Huberman: That was something else. So, we got the footage, brought it back, built this thing up. And then what happened was, in the subsequent year, the technology for VR really improved. So we decided we were going to go back. And I decided, for whatever reason, that I was going to cage exit also. I actually learned how to scuba dive for the first trip, but I’d stayed in the cage. And so, the second trip, we went out there and I brought a good friend of mine who was actually a mutual friend through Blake Mycoskie, Pat Dossett, is a former SEAL team guy. I brought Brian MacKenzie because Brian McKenzie learned how to scuba dive in a lake in Oregon. And his first ocean dive was a cage exit with great whites.

Tim Ferriss: Sounds about right!

Andrew Huberman: The guy has “Unscared” tattooed on his knuckles; I know he was featured in a number of your books.

So, it was Brian, Pat, me, and some other guys. We went out there with the intention of getting better footage, to create a very realistic VR experience of great white sharks. So what happened was, on the first day, I decided I’m not going to cage exit today. Let Pat go. He’s a SEAL team guy. He’ll do it. He did it, of course, masterfully, the first time. Went a few meters beyond everybody, because those guys aren’t competitive or anything. Anyway, it all worked out. But the first day I was in the cage, I went down, I’d been in the cage before and you’re breathing off of hookah line, which is up to the surface. You’re not on scuba. And the reason you don’t bring scuba is because you don’t want to take up too much space in the cage. So, the other divers, Muller and a couple other guys, had left the cage and I was there just watching the sharks and really enjoying it.

I’d been down there the previous year and these great white sharks, their girth is incredible. And they come at you like a Volkswagen and they’ll stop right in front of you and hover. They’ll eyeball you and then disappear into the darkness. It’s really amazing. And I realized, as I was down there, I’m like, “I’m alone in the cage this time.” I’d never been alone in the cage. We had a lot of sharks that day, so I was moving around and swiveling around a lot. And then all of a sudden, I had no air, nothing. Just nothing coming through the mouthpiece. And I looked up and the hookah line got all boa constrictored up. So, I popped up to it thinking “I’ll just untangle this thing,” and it’s like hard as concrete. I was like, “Oh, good.”

So I took another suck of air and nothing. And I looked down, there’s safety tanks in the two corners. So I spit out the mouthpiece, I dropped down to the safety tanks, opened them up, and the needle doesn’t move. They’re empty. 

Tim Ferriss: Oh, God.

Andrew Huberman: This is the biggest nightmare. And it’s interesting; we were talking about Costello. I had one thought at that moment, a totally inefficient use of mental space, but the one thought was, “I’m going to go home alive; I’m going to see Costello.”

He just popped into my head. So, this stuff really does happen, apparently. So nothing off the safeties tanks. So, I decided, “I’ve got to get out of here.” Well, there’s sharks everywhere, but I’ve got to get to the surface and you’re just desperate for air. So I pop up to the top of the tank and I’ve got a weight vest on, and I’ve got to take that weight vest off if I want to get up to the surface. Now the sharks actually don’t eat you when you’re outside the cage if you’re swimming toward them. They actually, if you loom on them, they steer away. That’s the way that these cage exit divers are able to avoid getting eaten. Or if you’re Ocean Ramsey, you just understand them and you’d swim next to them. But I was genuinely frightened and stressed. And so I thought, “Okay, I’m going to shoot for the surface.” I could see the silhouette of the boat.

“I’m going to shoot for the surface. I’ll either get eaten or I’ll drown, but I’m certain I’ll drown if I stay here.” And then what happened was, one of the divers, his name is Brock, saw me and started kicking back toward me. And he’s carrying this big vacuum cleaner size, VR thing. And that felt like an eternity, you know? He’s coming back to me, back, and he’s slowly — so now I’m just hoping if I pass out, I want to fall into the cage. If I float, I want to make sure I float up. But it was a good 20 or 30 more seconds, which doesn’t sound like very long, but it’s not like I’ve got a big gulp of air.

Tim Ferriss: That sounds like an eternity. That’s an eternity.

Andrew Huberman: It was an eternity. So he made it back. We did the share-air thing. But then we add a whole other problem, which was that, we’re sharing air, those guys are out there. We’re now on one tank and the safeties are empty. So now there’s a chance that we both might have to shoot for the surface. So, fortunately, everybody made it back in time and we got up to the surface. But I will never forget that experience. I do feel like I’m on borrowed time and I did feel quite traumatized by it. And I will say that that night I did one thing and the next day I did something else was, that night I was able to sleep, I did yoga nidra and I was able to calm my mind and my nerves.

And the next day, because I understand a bit about the relationship between trauma and exposure, I did go back down the very next day and I cage exited. And some people might think that’s foolish. I certainly didn’t do it to be tough or to seem like I’m tough. I did it because facing the trauma is the best way to purge the trauma, we know this. And cage exiting, for me, allows — allowed me, I believe, to report the experience, I feel nothing in my body, no tension, no stress, no quaking, or anything related to that. So I do think it’s been completely purged.

Tim Ferriss: I want to dig into what I read as a definition of fear from you. And just to hear more about your fascination with fear and where it comes from. So, here’s what I have, and you can fact check this, please. “Fear: it’s the anxiety that you feel when you don’t know what behavior can remove a feeling of helplessness in the face of a threat.” Does that sound right to you?

Andrew Huberman: You can’t have stress without anxiety. You can’t have trauma without stress. But you can have stress or anxiety without trauma. I think that the key variables are anxiety is a state of heightened alertness, it’s contracting in the visual feel, quickening of the heart rate, breathing, all the kind of standard stuff that we hear of sympathetic nervous system activation. But the mental component is one in which time is being sliced very finely, so you’re constantly anticipating and evaluating your environment and your internal state. Because oftentimes people are aware of their so-called interoception, they’re keenly aware of how nervous they are or upset they are. And this element of uncertainty, of being unable to predict when it’s going to pass, and this creates a kind of meta stress.

It’s like when people have trouble sleeping, then they create this meta-anxiety and insomnia. They’re — now they’re stressed about not sleeping, and so then it makes it even harder to sleep. The same thing with stress. The more we stress, the more we want the stress to pass. And I think that resolving the uncertainty element is powerful. And I think it starts by taking control of the mind through the route of the body. When our mind is not stable, whatever that means, but we’re not able to control our mental state, or it’s not where we’d like it to be, we need to look to the powers of respiration, of vision, of movement, of weight training, of running, to reorient the mind. I think it is futile to try and rescue thinking with thinking. And that’s not to say that thinking in an exploration of the mind, like with psychoanalysis or journaling, is not powerful, but for restabilizing our system, these brain states of mind and body, I think the body is the more powerful entry point.

Tim Ferriss: And have you always been fascinated by fear? Or why did that become a focal point?

Andrew Huberman: Probably because I was the kid that was last to drop in on the ramp. Probably because I have lived and existed with a fair amount of fear. This seems to have gotten better over the years. For instance, I can remember skateboarding home. There’s this bike path that used to connect the school that I went to at the back of some houses and I would push back through there at night. And I would start to imagine that terrible things were going to happen to me. I think that fear was a strong default and I can’t assign that to any earlier experience. I think I just had a lot of baseline anxiety and fear. And so resolving that and figuring out tools that people could use that I could use also to resolve those things really fast has been a major effort in my life, including my laboratory.

Tim Ferriss: I’d like to, if it’s okay with you, shift gears a little bit and just pepper you with a bunch of random questions that have absolutely no continuity with anything we just talked about.

Andrew Huberman: All right. It’s okay. Sure thing.

Tim Ferriss: All right. Because I just — I have this scratchpad full of these various things that I want to ask about often without a whole lot of context, just from various reading and so on. So, turmeric’s effects on DHT. Could you elaborate on this? A DHT, dihydrotestosterone, I’m guessing. So what should we know about DHT and turmeric’s effects on DHT? And I ask in part, because it’s something that I use all the time in cooking and there are also — there’s seems to be some research to suggest that products like Theracurmin, I believe it’s called as the brand name, might attenuate some risk related, say a neurodegenerative disease or Alzheimer’s. So I’d love to know more about this. Turmeric’s effects on DHT.

Andrew Huberman: Yeah. So brief endocrinology lesson on testosterone DHT. Testosterone is the androgen, of course, that’s responsible for muscle growth, deepening of the voice, aggression, sex drive, et cetera. But DHT, dihydrotestosterone, is made from testosterone through an enzyme called 5-alpha-reductase. DHT is the more powerful androgen, anywhere from 300 to 600 times the affinity for the androgen receptor. DHT is the — and its affinity for the androgen receptor, not too incidentally, is the basis of nandrolone deca, known in gym circles. Actually, a female runner, that was a good pick for the 1500, just got a four-year ban.

Tim Ferriss: Oops.

Andrew Huberman: For a nandrolone positive test. She claims, and her coach claims, that it came from a burrito containing pork with nandrolone. I actually would love somebody to go explore. We’re going to see more of this in the years to come. I’d like somebody to actually analyze meat for clenbuterol and nandrolone to just see — and I’m not happy that this happened. It’s a sad situation, but we could fairly say that there’s been a dark shadow cast by a burrito over the Olympic qualifications. 

Tim Ferriss: It’s like when all the sprinters were diagnosed as narcoleptics. You remember that?

Andrew Huberman: Oh, really?

Tim Ferriss: The modafinil? Yeah. They’re all on modafinil and various stimulants. And so they had these scripts from their doctors and letters saying they were all narcoleptics. It’s just amazing, the Venn diagram.

Andrew Huberman: Interesting. To get them quick out the blocks. That’s where the race is won, hear that gun, and get out the blocks. That’s — so, nandrolone is deca. The reason people take it, whether or not she took it or not, I don’t know, but the reason people take it is because DHT, as the more powerful androgen with this higher affinity, is the one that’s mainly responsible for libido and many of the cognitive effects of testosterone. One of the more powerful effects of testosterone is that because of the fact that there are androgen receptors in the amygdala, that it has a fear suppressing component to it and DHT testosterone, but really DHT, has a property of making effort feel good. That’s probably the main psychological effect of testosterone, aside from its effects on libido and the body periphery. So some people are very DHT sensitive.

If you’re somebody, for instance, that takes creatine and experiences hair loss very quickly, you’re probably DHT sensitive. That’s because creatine increases DHT. DHT will promote hair loss on the scalp, like my hairline’s retreating quite nicely, because of DHT receptors here. And it promotes beard growth. So it has these inverse effects on the face and on the scalp. But turmeric is a fairly potent DHT antagonist. Now whether or not it does that by occupation of the androgen receptor or some other mechanism, I don’t know. People will vary in their sensitivity. I am very sensitive to turmeric. If I take turmeric, my DHT levels plummet. And I’m not taking nandrolone, nor am I eating pork burritos.

But the sensitivity will vary. And you can predict that sensitivity by how you react to creatine. If you’re somebody that takes low doses of creatine, which many people do, and experience hair loss, chances are, when you take turmeric, you’re going to see a reduction in DHT. It means that your 5-alpha reductase system and/or this interaction between turmeric and the androgen receptor are, for whatever reason, more sensitive in you. Some people take turmeric and feel perfectly fine. I noticed an immediate blunting of all the good stuff, let’s say, that DHT and testosterone do when I take even a minimum of turmeric. Now that doesn’t mean I can’t have a little bit of turmeric in a drink, like a juice drink or something, but dosing turmeric is not something that I do or that I recommend for people.

Now, women do make a little bit of DHT. It might be a whole different story with them, but I think for men, you probably just want to do the experiment. It’s quickly reversible. If you stop taking turmeric, so you could evaluate this, some people will be fine. But you could do a blood test. You could do it subjectively.

Tim Ferriss: Is finasteride — Propecia — that is often used for mitigating hair loss. That is — I think it’s a 5-alpha reductase inhibitor. Would that also have the effect of decreasing DHT levels? I want to say there are anecdotal reports, and people, please do your own homework, go to PubMed and do some research. But I want to say that least, amongst strength athletes, that I’ve heard anecdotal reports of Propecia use correlating to decreases in strength gains for male athletes.

Andrew Huberman: Yeah, absolutely. And it certainly can reduce DHT levels, certainly, more for those that are sensitive to it. Just to underscore how powerful DHT is, we have what are called primary and secondary sex characteristics. Secondary sex characteristics are like body hair, deepening the voice, et cetera. But the primary characteristics, like the presence of a penis or not, and this is independent of gender, this is just biological sex, it’s encoded by the Y chromosome. That’s entirely controlled by DHT during development. And masculinization of the brain is a separate pathway. But there’s this phenomenon that I think is in the Dominican Republic, a genetic disruption in some of these pathways and there are the — people can look this up, the so-called guevedoces. This is a famous story and endocrinology of children that look female at birth by genitalia, and then because of a surge in DHT later, they literally sprout a penis at about, and testicles descend, at about age 12. Guevedoces.

Tim Ferriss: Wow.

Andrew Huberman: And there’s a whole story there. It actually was part of the story that helped neuroendocrinologists and developmental biologists understand the role of 5-alpha reductase in testosterone’s conversion to DHT. Fascinating biology there. Much too much to go into now in detail, but people can look it up online. DHT is powerful in development, and it’s powerful throughout the lifespan. And so, you want to keep levels of DHT appropriately high. But don’t take nandrolone if you’re sprinting in the Olympics. So that’s not the way to get your — nandrolone is not the way to get your DHT.

Tim Ferriss: Yeah. Even if you do get it through anabolic piggies, which is — it’s just like, there’s so many more cost-effective ways to make pigs grow. Deca drabble and injections is probably not high on the list.

Andrew Huberman: They just need to have — they need natty menus. Right? They need menus that are like — if you’re an Olympic athlete, please just prepare your own food.

Tim Ferriss: Yeah, yeah, yeah, exactly. Let’s see here. So, so many directions to go here. It makes me wonder also, if anyone has looked at turmeric or curcumin, or whatever the actual compound is responsible for this DHT inhibition, whether it’s via 5-alpha reductase or otherwise, on pregnancy and birth gender. I’m wondering if that would have any effect. If DHT is suppressed in a woman who is pregnant, if that would have any effect on birth gender.

Andrew Huberman: That’s a topic that I don’t think the experiments ever been done, but my postdoc advisor, Ben Barres, was transgendered. And it’s an interesting story. Briefly, he was an identical twin. He, from a very early age, he felt entirely uncomfortable in a female body. He knew he wanted to be male from a very young age, long before puberty. He — his sister who I’ve interacted with as well is perfectly happy being a woman, enjoys being a woman. And they’re identical twins. And their mother was actually treated with an androgenic drug during pregnancy. And then Ben, unfortunately, passed away of pancreatic cancer a few years ago. He was an incredibly accomplished neuroscientist and physician. His name is Barres, B-A-R-R-E-S. There are a number of obituaries; I wrote one for Nature that describes his life and his transition and some of the biology. But nonetheless, Ben and I spent about a year before he died, I recorded a lot of conversations with Ben that I haven’t released yet, talking about what it was like to be a girl, what it was like to be a woman, what it was like to be a man, later in life. Just as I — he’s a close friend of mine, I want to understand that. And he described that this was an immediate effect. As soon as he knew there was a difference between boys and girls, he knew that he was in the wrong body. He likened it to, if you woke up tomorrow and you were in a gorilla’s body, that’s how uncomfortable it was, knowing that — that’s how he described it. And he thought that perhaps, this early androgenic drug treatment, might’ve shaped his brain differently than his sister, so — 

Tim Ferriss: Raises so many — so many interesting questions about, phytoestrogens or some of these xenoestrogens, and the environmental inputs that could affect that entire biochemical cocktail to different outputs. Testosterone. So, we’ve talked a little bit about DHT. There’s a Goldilocks range depending on your gender and your objectives for testosterone. Are there any particular supplements that you use to — I hesitate to use this word because it’s so goal-dependent, but optimize your testosterone or DHT levels or reduce sex hormone, binding globulin, or whatever. If you’re toying with your androgens, how do you like to do it?

Andrew Huberman: Optimizing and or understanding testosterone, I think, is vital for men and women, because it’s so powerful. Obviously, get your sleep right. That’s an important one. And you do that through — so, that’s an indirect effect. Stress, keep stress, chronic stress to a minimum, that’s an indirect effect. Train hard, but not too long, that’s an indirect effect, mostly. In the supplementation space, there are two things that have worked very well for me, and that I’ve recommended to a number of people that have worked well for them, and those two things are Tongkat Ali, which at 400 milligrams per day, is thought to reduce sex hormone-binding globulin, because if — for those that don’t know, testosterone can exist in a free or bound form. 

People hear “binding globulins” and they bind up testosterone, prevent free testosterone, they think this is terrible. But actually, albumin and sex hormone-binding globulin are wonderful because they ensure that whatever testosterone you make will be delivered to your tissues over a long period of time. And different tissues need different amounts of testosterone. And so, you don’t want to plummet sex hormone-binding globulin, but Tongkat Ali, either through reducing sex hormone-binding globulin, or through direct effects on increasing androgen release, will increase your testosterone. Now, the way to explore this, and I’m not saying anyone should do this, you definitely want to work with your physician, but the way to explore this is 400 milligrams per day taken once per day, early in the day, because it can have a little bit of a stimulant effect, make you more alert. That works well.

It does need to be taken chronically. It tends to work better as you get into the second and third month of use. And I don’t see any reason to cycle it unless somehow something spikes on your liver enzymes or something. The other supplement that is quite useful is Fadogia agrestis. Fadogia agrestis is one of these plant alkaloids that — I think it comes from a Nigerian shrub. I might have that wrong. But Fadogia agrestis acts as a luteinizing hormone mimic. And so, it actually stimulates the testes to produce more testosterone.

Tim Ferriss: So, it’s like HCG. It’s like a — it’s a — 

Andrew Huberman: It’s a bit like HCG, but it, for whatever reason, it doesn’t seem to increase estrogen, which is unique because HTG will increase estrogen. Now, just anecdotally, I started using those in combination. So it’s 400 milligrams of Tongkat Ali. I have no relationship to the company so I can mention where I get it from, although I hope they don’t sell out as a consequence. Solaray makes a good version of this. Sometimes these things are packaged in with other things, but Solaray has a pure form. And then, Fadogia agrestis, I think it’s Herbal Elixirs, makes a Fadogia agrestis.

And some people make the mistake of taking far too much Fadogia agrestis. I think, on the bottle, they recommend two to three times a day. One 425-milligram capsule, I believe, is more than sufficient. And anecdotally, for me, what this did is it increased my total testosterone by about 200 points. So I fell in the middle of the range. I was neither high nor low. I was at about 600, hovering somewhere around 600. These two supplements consistently bring it up into the high sevens or low eights, which is in the direction that I wanted to go. 

Tim Ferriss: Do you think that Fadogia agrestis, if it is luteinizing hormone similar, meaning it’s a mimic of sorts, do you think that would have any — I guess it probably would have a down-regulating effect on endogenous production of LH.

Andrew Huberman: Well, what’s interesting is when I’ve done my blood work twice a year, at least for me, it did not downregulate LH. 

Tim Ferriss: Weird.

Andrew Huberman: Which is nice, because things like HCG definitely would downregulate LH, people who take testosterone cypionate, so-called TRT, or similar, we’ll see a downregulation in luteinizing hormone. The — so, Fadogia and Tongkat Ali, I mentioned, because they’re an intermediate between doing nothing with respect to supplements or taking things that don’t really work. There are a lot of those out there. Or taking the full plunge into TRT.

And I’ll just mention, if I may, about TRT, there’s a lot of interest and excitement in TRT. They now even have what’s called sports TRT, which is not — 

Tim Ferriss: And just for people who don’t have the context, if — I’m not sure if you already named it out, but testosterone replacement therapy, TRT.

Andrew Huberman: Right.

Tim Ferriss: What sports tier? Is this like med spa-type stuff?

Andrew Huberman: Yeah. So, people were probably wondering, “Wait, you’re a neurobiologist. Why do you know so much about this stuff?” Well, I have the good fortune of doing work with various high-performing communities. And there’s just a lot of discussion around hormone and neural augmentation. And so I’m not making recommendations. What I generally do with those communities, and what I’m doing now, is point people to the fact that there are things that lie somewhere between doing nothing and going the prescription drug route.

Tim Ferriss: Eating pork burritos.

Andrew Huberman: Yeah, exactly. Exactly. In the realm of TRT, testosterone replacement therapy, the typical dosages that people use are 160 to 200 milligrams a week, but the way it’s administered doesn’t match the biology. I think this is a serious problem that needs to be dealt with. Typically, if you get a prescription, you’ll go in, they’ll give you one injection of anywhere from 160 to 200 milligrams. And then you go back two weeks later and you get another injection.

The testes normally make anywhere from about five to 10 milligrams of testosterone a day. So, if you’re taking 160 milligrams of testosterone on one day, you’re going to do set in motion all sorts of cascades of aromatization and estrogen conversion into DHT that you might feel terrible, then great four days later, and then so-so two weeks later. The way people are doing this now, more intelligently, is to do their injections at home, either subcutaneously or into muscle. And every third or fourth day to take a low dose of maybe 40 milligrams, and to dose it more evenly. Because these long-lasting forms like cypionate do release over time. But sports TRT is this intermediate that’s been created on the internet where people are neither doing testosterone replacement therapy to get levels up to normal or high normal, nor are they doing what the gym rats call blasting.

They’re not taking three, four, 500, they’re taking 200 a week or 300 a week. And that, the amount of self-directed pharmacology that’s happening out there is pretty incredible. And I don’t pass judgment, everybody, it’s your life to live, but there are a lot of horror stories too. You can really mess yourself up by getting androgen levels too high. I’m a fan of gently moving into the supplementation space for this, seeing how it works, doing a blood test. And then if people want to do TRT over time, that certainly they’re right, that’s not my place to judge and you need a prescription anyway, so you’d have to talk to a doctor.

Tim Ferriss: Yeah. Yeah. And just a couple of additional thoughts on all of this stuff. Well, first, the lower dose, higher frequency regimen, can also be applied to many things, right? Growth hormone would be another example from the same portfolio of interventions/augmentations a lot of folks would use. And separately, I would say, and please, please feel free to correct me or fact check on this but, whether you’re eating pork burritos, injecting yourself with anabolics of different types, or eating deer antler velvet, or whatever the latest fad is that people claim increases testosterone, if you dramatically increase your testosterone levels, if you are not taking an anti-aromatase, you are also going to increase your estrogen levels, even though it depends on the anabolic, obviously, nandrolone is very different from different types of testosterone, and so on, which some are more anabolic, some are more androgenic. But if you suddenly wallop yourself with much higher levels of testosterone, you are also going to — a portion of that will be converted to estrogen.

And so it’s just something to be aware of. It’s very hard to get a biological free lunch.

Andrew Huberman: Yeah. That’s right.

Tim Ferriss: And if you’re feeding yourself a bunch of stuff and your testes, like the Siberian — what were they? Albino rats?

Andrew Huberman: Siberian hamsters, that’s right.

Tim Ferriss: Yeah. Siberian hamsters.

Andrew Huberman: That’s right.

Tim Ferriss: If your balls go from whatever your comfortable ball diameter is down to like raisins, you may require post-cycle therapy, PCT, various drugs, to successfully off-ramp from these types of interventions. Unless, like some powerlifters, you’re just going to be loaded all year-round 365/24/7, which is obviously your choice, if you want to do something like that. But good idea to get medical supervision for all these.

Andrew Huberman: Definitely. And along those lines, I should just mention, well, I will say that Fadogia tends to have the opposite effect on the testicles. It actually will cause a fairly, not pronounced, but it increases testicle size. That’s a pretty strong effect or media effect of Fadogia. The other thing is that, right now, there’s a lot of excitement about peptides. People are like, oh, the so-called secretagogues, it sounds like synagogue, but it’s secretagogue. Whereas these are not taking growth hormone, but taking peptides that promote growth hormone release. And then people are taking gastric peptide this. And here’s the deal, things that make us feel more vital like testosterone, DHT, growth hormone, generally, will shorten your life. I know that’s a bit of a controversial statement, but if you step back and you just ask yourself, what is the most vital energetic phase of your life? It’s puberty. When all these hormones are really high. And puberty is the most rapid period of aging that any of us go through. I was talking about this recently with a longevity researcher, and it’s kind of interesting that all the attempts at increasing life are like starving yourself, which is catabolic, reducing blood sugar, which is catabolic. And that’s on the opposite side of all these things like testosterone, which is anabolic, insulin, which is anabolic, growth hormone, which is anabolic. And so anabolism sounds like a great thing, although it does sound remarkably similar to cannibalism, but growth and vitality, libido, strength, et cetera, that all sounds wonderful, and in its proper form and context, is wonderful. But the reason why I think we see people dying early who do a lot of growth hormone and testosterone is because they’ve effectively created a third and fourth round of puberty. You’re accelerating aging. And so, I think vitality and longevity always have to be balanced with one another.

Tim Ferriss: Yeah, totally. And yeah, we could go for hours just on this one topic. One other cautionary note. Well, two actually. Number one: unless you’re type one diabetic, don’t inject insulin. There are athletes who do this, but you can very easily kill yourself. The second is if you’re taking a lot of growth agents, some of them are not selective to skeletal muscle tissue, and you may, as a male, end up looking like you’re in your second trimester from enlarged organs. And guess what? When you get off of those drugs, your organs don’t automatically resume their smaller size. This is also why certain baseball players and so on have gone up multiple helmet sizes. It’s not from pork burritos. And those effects are durable. You can’t just hit undo on those things.

Andrew Huberman: Very, very good point.

Tim Ferriss: Yeah. Pays to be cautious. All right, so a few other things. Cognitive enhancement, or cognitive boosting supplements, much like the testosterone playing field, there’s a clown car full of ridiculous propositions. There are, of course, then the prescription and the sort of medical route where there are certain things that’ll help. Some things like nicotine can be tremendously effective, but come with some possible downsides associated. Do you have any particular thoughts on cognitive enhancement or how you think about that, specifically on the pharmacological/supplement side? I know there are many other things that we could also talk about.

Andrew Huberman: Yeah. I’m glad you mentioned many other things. I won’t list them out again, but I do believe that the most powerful nootropic and cognitive support is going to come from quality sleep and — 

Tim Ferriss: I 100 percent agree.

Andrew Huberman: Yeah, so it’s night and day. On the pharmacologic side, I think alpha-GPC has real effects that are supported by quality peer-reviewed studies, including some studies looking at offsetting age-related cognitive decline. So generally, it comes in capsule form of 300 milligrams or so. I think taken occasionally, or more than occasionally provided it’s fairly early in the day, it does increase focus without increasing the kind of sympathetic arm of the nervous system, in other words, without increasing arousal and alertness too much.

So I do think alpha-GPC is a useful supplement, and I use it from time to time. If I’ve slept well, I don’t take it. If I really want to push a workout hard or a work session, a writing session, or data analysis session hard, I’ll take 300 milligrams of that and drink a couple of espresso or drink some mate and some water. Stay hydrated. Hydration is a big one for cognitive function, and it’s one that people often overlook. But the simple rule is that — this is what I call the Galpin Equation, because Andy Galpin, who’s a great exercise physiologist, came up with this for physical work.

But it turns out to work for cognitive work, too, which is that basically your body weight in pounds divided by 30 will give you the number of ounces of water that you should drink about every 20 minutes when exercising or doing mental work. Might seem like a lot. There might be an extra trip to the bathroom or two, but it’s worth it. Dehydration is a subtle but very pernicious creep, where you start having a hard time focusing your eyes. You just feel like you want to go to sleep. That hydration factor is real. So drink plenty of fluids, especially if you’re ingesting caffeine, which of course is a diuretic.

Tim Ferriss: My personal favorite vehicle for caffeine remains yerba mate. I just absolutely adore the effects of yerba mate. I’m not saying it’s for everyone, but you have the caffeine, and, I might be getting the pronunciation off, you also have, I believe, theophylline, which you would find in green tea, and theobromine which you would also find in, say, dark chocolate. Side note trivia for folks: Theobromine from “theo” as in theosophy; theobroma, “food of the gods.” So that’s kind of fun.

Andrew Huberman: Oh, I didn’t know that.

Tim Ferriss: Yeah, but the pharmacokinetics of those are all different. So unlike coffee, which I have a love/hate relationship with because I metabolize it so quickly that I get this sort of Snickers bar sugar high of caffeine for a very short time, 20 or 30 minutes, and then my baseline of sort of subjective perceived energy is lower than when I started. So what happens then? I become a crackhead who drinks eight cups of coffee a day. Not so with yerba mate, especially when you’re kind of titrating it in the way that they would consume it in a place like Argentina or Uruguay, where you’re just kind of sipping it slowly.

Andrew Huberman: It’s great stuff.

Tim Ferriss: Yeah.

Andrew Huberman: I found a brand that, and I don’t have any relation to them, but I found one that I particularly like. It has a weird name, but it’s Anna Park. It’s an organic yerba mate. I don’t know who Anna is or her park, or maybe her name is Anna Park, but it’s nice. It has just the right amount of that tobacco flavor, but it’s not burnt to the point of feeling kind of overwhelming.

Tim Ferriss: Yeah.

Andrew Huberman: The other thing about caffeine that’s kind of interesting is that most people would benefit from waiting 90 minutes to two hours after waking to ingest their caffeine.

Tim Ferriss: Oh, interesting.

Andrew Huberman: The way caffeine interacts with the adenosine receptor — remember, you get sleepy because of time of day with that whole circadian clock mechanism, but also because of the buildup of adenosine in your system. That’s the sleepiness factor, really. And when you wake up in the morning, if you immediately compete out any residual adenosine, you lose the benefit of that cortisol pulse, essentially clearing out the rest of the adenosine. And so a lot of people, despite the pain of having to do this the first day or two, feel much better throughout the day, less of that cracked out kind of rise and crash feeling on caffeine, if they delay their coffee or mate for about 90 minutes to two hours after waking.

Tim Ferriss: Oh, that’s great to know. Side note for people who may want to do some further research and reading into caffeine: the name Roland Griffiths has come up multiple times on this podcast. He’s an incredible scientist and researcher based at Johns Hopkins. He is one of the most, I would say, esteemed researchers alongside, say, Matt Johnson, Roland has just been at it for longer with respect to psilocybin and psychedelics. So he’s associated with that. But prior to psychedelics, he was one of the world’s foremost experts in caffeine metabolism.

And so he has published and performed studies related to caffeine that are intensely interesting. So for people who want to dig deeper into that, Roland Griffiths is a great resource. One thing I’ve been wondering — because there are drugs that you can use to counteract other drugs, right? So if you go to Bellevue and you’re at the psych ER, and someone comes in just high out of their mind on cocaine, right? There are medications they could be given to try to take them down a notch or two or three or ten, like haldol, or — I’m not sure if that’s used any longer, but there are many different drugs that could be used.

In the case of caffeine, let’s just say someone named Jim Barris, just for sake of argument, is working on his laptop at a restaurant and said restaurant has excellent service, which means they also have the never-ending cup of coffee. And so, before he knows it, he’s had five cups of coffee, even though he only ordered one coffee. Is there a way to sort of — let me think about this. To reverse or counteract the effects of caffeine on adenosine, such that you can actually get to sleep, right? So if you hit the golf ball and you’re like, “Oh, fuck. Looking at the half-life of caffeine, there’s no way I’m getting to sleep until like three in the morning,” is there any way to address that, or is it just fait accompli and you’re more or less screwed?

Andrew Huberman: Yeah, one direct and two indirect. A direct way to do that is increase your glucose. You know the whole notion that you can soak it up by eating some bread?

Tim Ferriss: Uh-huh (affirmative).

Andrew Huberman: You will see a blunting of the stimulant effect. Now, whether or not that’s also due to some, I don’t know, increase in serotonin or something from the carbohydrate isn’t clear; but yeah, you could have a bagel or two or whatever it is that — a compatible carbohydrate. These days, carbohydrates are such a complicated thing for most people. I like carbohydrates, especially late in the day. I either fast and go low-carb/no-carb during the day, because that lets me focus. That’s a meat and salad during the day, or not eating for portions day, and then at night, I eat pasta and rice and I eat very little protein and sleep like a baby. That’s what works.

But the other way is to take theanine. So before we were talking about theanine in reference to pre-sleep supplementation, 30 or 60 minutes before sleep, but 100 to 200 milligrams of theanine will take the jitters out of a caffeine experience. And in fact, so much so that a lot of energy drinks now are starting to include theanine as an attempt to get you to ingest more of those energy drinks, because they understand that at some point, people hit threshold and they feel so wide-eyed and wired that they’re not going to consume more, so they’re tricking you this way and it does indeed work. The other thing is, if you ever really need to sleep, I mean, again, be cautious, do what’s compatible with your physician’s advice, but GABA, you can buy GABA and glycine in capsule form.

So a gram of GABA, a gram of glycine, in combination, that’s more of a heavy hit over the head. But if you’re having a hard time getting to sleep, that could help. I don’t recommend people those chronically, because GABA, of course, is a neurotransmitter, and I don’t believe really in taking things that are very close to the actual thing that you’re trying to manipulate. For instance, I’m not a fan of taking L-DOPA. Why would I do that? I don’t have Parkinson’s. But people will take Mucuna pruriens, which is essentially 99 percent L-DOPA, and you’ll get really, really elevated, but then you’ll really crash for a day or two. So I think that pulling on the marionette strings a little bit from a distance is better than taking the specific compound that you’re trying to replace, unless there’s a clinical need, of course.

Tim Ferriss: One more topic. And since we’re at about two hours and 30, we’ll wrap up in just a little bit, but the vagus nerve. What is the vagus nerve? What is the latest and greatest? Why is it of interest?

Andrew Huberman: Yeah, so the vagus nerve is a nerve network. It’s many nerves. It could even be thought of as its own major branch of the peripheral nervous system. It comes out of the brain, basically, and connects to all the organs of the body. And this is the pathway by which a mental state can influence our digestion, our heart rate, our breathing. We talked earlier about HRV, heart-rate variability. The vagus is an important component to the slowing down of the heart rate when we exhale. It’s a very important pathway and it’s bi-directional, so the organs of the body that I just mentioned, the lungs, the gut, the heart, et cetera, the spleen, they also send nerve connections back to the brain. And there’s been a lot of interest in the vagus as a purely calming system, and that’s simply not true. The medical textbooks call it, appropriately, cranial nerve 10, it’s in the parasympathetic arm of the nervous system, which suggests that it’s all-calming, but actually it’s not. It has branches of it that are kind of stimulating, as well.

So in the kind of wellness and self-help community, you hear, “Oh, you should do this thing of rubbing in front of your ears. That’s a branch of the vagus that calms you down,” or, “Stimulate the vagus to calm down.” Now, in neuroscience laboratories, and even in some human neurosurgery laboratories, the way that you get people more alert — in fact, a form of early form of depression treatment is to stimulate the vagus, and it makes people more alert and more positive and excited. So vagal stimulation can easily cause increases in alertness.

Tim Ferriss: How do they do the stimulation?

Andrew Huberman: This is a beautiful story. A colleague of mine, perhaps, at least to my mind, the most impressive neurobiologist I know, a guy by the name of Karl Deisseroth, he discovered and invented channelrhodopsins, which are from algae, essentially, that are light-sensitive. Clone the genes, you can put those genes into neurons, you have to do this by viral injection, and then you have a little blue light diode that will allow you to stimulate just those neurons locally. Karl’s a psychiatrist, a bioengineer, and a neurobiologist operating at the very highest level. Actually, there’s a book that he just published that I’m listening to now that is — it can only be described as beautiful. It’s a description of the landscape of psychiatry and his attempts to build tools that are better than drugs to manipulate the nervous system. It’s called Projections, and it’s a beautiful read. You’ll learn a ton of neuroscience.

Karl is well on his way to win every big prize in science. He’s got all of them right now, except the last one. And I’m not on the committee that votes for those, but he’s remarkable. Also, has five children, happily married. His wife is a phenomenal scientist and physician. One of the reasons I like being at Stanford is because the mean is so very high, but Karl shifts the mean. He’s that dot way out there. In any event, there’s a beautiful article that I can reference, send you the link to, in The New Yorker, where Karl is sitting there talking with his patient and she has suicidal depression. And she’s describing her lack of desire to live. And then, he cranks up the intensity on the stimulation of the vagus. And in real-time, she starts describing how she actually would be interested in applying for a couple of jobs this year. This is happening in the order of seconds by stimulation of the vagus.

Tim Ferriss: What is the machine? How does it connect to her?

Andrew Huberman: That one is an implanted electrical stimulation device that’s placed probably on — there are many branches of the vagus, and so on a branch that isn’t going to impact breathing.

Tim Ferriss: Right.

Andrew Huberman: Sometimes people have challenges with swallowing, so there are problems with doing that. Karl, a big part of his mission, is to create very small light diodes that can stimulate nerves without the need to inject viruses and things of that sort.

Tim Ferriss: Wild.

Andrew Huberman: I think at a time not too far from now, thanks to his work and the work of other bioengineers, we are going to be able to stimulate, for instance, just the serotonin neurons in the raphe that lead to active coping. This is a well-known phenomenon. And whereas when you take Prozac or Zoloft or one of these other drugs, it will stimulate those neurons, but will also stimulate the serotonin receptors on the spinal neurons that control the sexual response, and that’s why they have sexual side effects. So more precision is coming.

So, as it relates to the vagus, the other way in which the vagus is stimulating is something that we do quite often. We have neurons in our gut. We all hear about the gut-brain axis. And people say, “Oh, it’s your second brain,” but very seldom does anyone actually describe how the second brain actually impacts the other brain. And the simple way to put this is: We have these neurons that live in the mucosal lining of our gut, and those neurons sense three things. They sense fatty acids, so they like fat. They sense amino acids. They love that umami flavor, and they love amino acids because that’s vital to protein repair, metabolism, et cetera. Protein synthesis, excuse me.

And they like sugar. And when you eat something that has fatty acids, amino acids, or sugar, these neurons send a signal that are part of the vagus nerve up to a little cluster of neurons in your neck called the nodose ganglia. N-O-D-O-S-E. And the nodose ganglia then stimulates your deep brain centers to release dopamine. And the amazing thing about this — these are data from a guy named Diego Bohorquez at Duke University. The amazing thing about this system is that even if you numb the mouth, even if you just gavage a person or an animal and put the substances into the stomach, you will seek more of these foods.

And so, you’re actually seeking sugar, amino acids, and fat more when you ingest those foods independent of how they taste, and so this has a whole set of implications for hidden sugars and the fact that so many of the foods we eat, we just find ourselves eating more of them. We think, “I don’t even know why I’m eating this.” It’s because these neurons in your gut are stimulating dopamine release, and as we talked about before, dopamine isn’t a molecule of pleasure. It’s a molecule of making you want to do whatever led to dopamine release.

Tim Ferriss: Yeah. The Molecule of More.

Andrew Huberman: The Molecule of More. So the vagus is multifaceted, and we will soon hopefully subdivide it into some more meaningful pathways. I don’t like to knock on anyone else’s work, but I do think that most of what you read out there about the vagus and what it does, and various theories about it, are partial truths to total nonsense. But they are partial truths to total nonsense that were grounded in the biology as we understood it at the time, and just a lot more has been understood in the last 10 years or so. So no disrespect to those people, but it’s time for a revision.

Tim Ferriss: Maybe two or three more questions, and then we’ll go get some food or something along those lines. The first is what books have you gifted the most to other people? Or are there any books that come to mind that you’ve gifted often to other people?

Andrew Huberman: Yeah, well, I love poetry and it’s almost cliche now to say this because so many people like his work, but I think David Whyte’s work is just beautiful and is a wonderful kind of entry point to poetry. I’m also a big Wendell Berry fan. He’s written a lot about farming and the natural world. And I’ve never met him, but I’m a huge Wendell Berry fan. I’ll sometimes give Wendell Berry books as gifts. The book that I think is perhaps, at least to me, the most beautiful book of all is Longitude by Dava Sobel about the history of the discovery of timekeeping at-ocean, which is not a trivial problem to solve.

And it’s just a beautiful story of how scientists, or in this case a particular scientist, merged the quest for a technology with a scientific problem with adventure, and going out on boats and risking one’s life for the sake of science is something that resonates with me a bit. And it’s a beautiful, short book, and it’s very accessible to anybody, whether or not you have a background in science or not, and she’s absolutely a wonderful writer. And so that’s the one I gift most often.

Tim Ferriss: Is there a particular David Whyte book or starting point that you might recommend?

Andrew Huberman: I own several of his books, but I confess that I’m forgetting the titles now. What’s interesting about David White is that his poetry is best consumed by listening to him read it, because he does this thing of repeating things twice, and his cadence is so impressive. Even though I loathe to kind of push people toward online, do buy his books, but I would suggest just going online and listening to a YouTube video or watching YouTube video of David reading one of his poems. He’s onto something. The thing about poetry that’s so fascinating to me is the same reason why I love anything sung by Bob Dylan or Joe Strummer, is that the words don’t necessarily make sense in the pure cognitive landscape. They’re tapping into some sort of deeper layer of the nervous system that defies the normal structure of sentences and thoughts. And so I think good poets are accessing the subconscious, and it has nothing to do with rhyming. It has to do with accessing some layer of neurobiology that we just don’t have a name for.

Tim Ferriss: Andrew, this question is sometimes a complete dead end, and I’ll take the blame for that if it is, but just to go fishing and see what we catch here: If you could put anything on a gigantic billboard, metaphorically speaking, to get a message out, quote, an image, a word, could be anything, a quote from someone else, anything at all, to billions of people, what might you put on that billboard?

Andrew Huberman: Well, assuming this is a big billboard, I could probably squeeze two things on there, but I would diminish the impact of either one. It’s so simple, but it at least has been the most useful thing in life to me, credit goes to the Oracle, which is, “Know thyself.” If there’s one thing that’s a really useful pursuit is to take a really good stock of what you’ve come into the world with and where you happen to be at present. Get really honest about that with yourself. And in doing that, it illuminates the path to filling in the gaps and improving oneself. And knowing thyself is a dynamic process, and the answers to knowing thyself and what that is will change over time. But that is the question that I think everybody, as soon as we are able to, should be asking ourselves and constantly updating.

Tim Ferriss: “Know thyself.” What was second pick? You can put it on the other side of the billboard.

Andrew Huberman: Yeah. The other one was a far weaker one, I think, but: use the body to control the mind. I really worry about the current state of the world, where people are so unable to regulate their autonomic nervous system. They’re stressed, they’re angry, they’re pissed. And look, I suffer from this, too. Sometimes a comment on whatever, I’m mostly on Instagram, but sometimes on Twitter, and I notice all this anger and stuff, and I start getting pulled into it from time to time. I regulate my behavior, but I don’t respond. But we’re all subject to this.

But almost all harm, almost all self-harm, and unfortunate things in life are the consequences of a poorly regulated autonomic nervous system. We say the wrong thing, we do the wrong thing, we’re impulsive, et cetera, and I think controlling the autonomic nervous system is simple in one sense and challenging in the other. “Simple” in the sense that the tools exist. I do believe that respiration and vision are the two ways to control the autonomic nervous system in real-time. The best ones. And at the same time, it’s very hard to do, so we have to remind ourselves, that’s why I’d want to put it on the billboard, that when your mind isn’t where you want it to be, use your body to control your mind.

Tim Ferriss: I love that. I’m going to use that on a long hike with the pooch a little later today. And we’ll also include, for everybody listening, show notes with links to various resources, all the resources that we’ve discussed, so the yoga nidra, the various types of breathwork; and I’ll also add a name, which is Leah Lagos. Dr. Leah Lagos has done a lot of really good work looking at resonance training, using breathwork for improving HRV. Although, improved HRV is really just a proxy for all of these other desirable outputs and effects in the world and in life, so we’ll include all of that in the show notes. Andrew, we’ve covered a lot of ground. Is there anything else that you would like to mention or say or point people to, any requests of the audience, anything at all that you’d like to add before we wrap up for today?

Andrew Huberman: Thank you. Well, we mentioned some of the things at the beginning. I teach neuroscience on Instagram at Huberman Lab. Those are resources, brief snippets anywhere from one to three minutes, about neuroscience, exciting papers I see, a lot of tools. It’d be wonderful if people want to check out the podcast. We cover a lot of topics, not just neuroscience, and we batch those by month so that we do four or five episodes in one thing like hormones and then move on to something else. And I suppose one request would be — we have this saying in a laboratory, it’s certainly not unique to laboratories, which is: “Watch one, do one, teach one.”

And what would be most gratifying for me would be if people find tools that they find useful and that they learn about them, that’s the watch one part. That they do them, they apply them in their own life and modify them if you like. And then, I think the way the world works best, at least in my view, is when people go on to teach those tools. And attribution isn’t required. As I always say, I wasn’t consulted at the design phase and I don’t know anyone else that was either. So Mother Nature and biology deserve credit for all this, and so if people would like to learn, practice, and teach, I like to think that the world can improve by virtue of sharing of tools.

Tim Ferriss: I love it. I dig it, man. And there are a number of places people can follow you and should check you out. As you mentioned, the Huberman Lab podcast. and @hubermanlab on Instagram and Twitter.

Andrew Huberman: I lost you there, Tim.

Tim Ferriss: This has been so fun, and I really appreciate all the time It’s been a real pleasure spending time with you, Andrew, and I look forward to many more conversations. I’m feeling that people will want a round two. So until then, thanks to you, and thanks to everyone for tuning in.

The Tim Ferriss Show is one of the most popular podcasts in the world with more than 600 million downloads. It has been selected for "Best of Apple Podcasts" three times, it is often the #1 interview podcast across all of Apple Podcasts, and it's been ranked #1 out of 400,000+ podcasts on many occasions. To listen to any of the past episodes for free, check out this page.

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One Reply to “The Tim Ferriss Show Transcripts: Dr. Andrew Huberman — A Neurobiologist on Optimizing Sleep, Performance, and Testosterone (#521)”

  1. This was an awesome episode. The explanation of the physiology of neural retina stimulation made a lot of sense. I have a better understanding why the outside morning walks during the pandemic made me feel better than I did going to the gym. Thank you