Hey, everyone, welcome to the Peter Attea drive. I'm your host, Peter, into you. Theo Drive is a result of my hunger for optimizing performance, health longevity, critical thinking, along with a few other obsessions along the way. I've spent the last several years working with some of the most successful top performing individuals in the world, and this podcast is my attempt to synthesize what I've learned along the way to help you live a higher quality, more fulfilling life. If you enjoy this podcast, you can find more information on today's episode and other topics at Peter tia MD dot com. Everybody welcome to this week's episode of the drive. I'd like to take a couple of minutes to talk about why we don't run ads on this podcast and why.

Instead, we've chosen to rely entirely on listener support. If you're listening this, you probably already know. But the two things I care most about professionally are how to live longer and how to live better have a complete fascination and obsession with this topic. I practice it professionally, and I've seen firsthand how access to information is basically all people need to make better decisions and improve the quality of their lives curating and sharing this knowledge is not easy. And even before starting the podcast, that became clear to me. The sheer volume of material published in this space is overwhelming. I'm fortunate to have a great team that helps me continue learning and sharing this information with you. To take one example, our show notes are in a league of their own. In fact, we now have a full time person that is dedicated to producing those. And the feedback has mirrored this.

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And as I said, we're not taking Adolfas from anyone. But instead, what I'd like to do is work with companies who make the products that I already love and would already talk about for free and have them past savings on to you again. The podcast will remain free to all. But my hope is that many of you will find enough value in one the podcast itself and to the additional content exclusive for members to support us at a level that makes sense for you. I want to thank you for taking a moment to listen to this. If you learn from and find value in the content I produce, please consider supporting us directly by signing up for a monthly subscription. My guest this week is Matthew Walker. Many of you are familiar with Matthew because in April of this year we released a three part series with him. The response to this was overwhelming. In fact, it was among our most popular podcasts to date, and as a result we decided to do a special A m A with Matthew hosting and me asking the questions on behalf of our subscribers. So what you have here today is what I would describe as three hours of the best Q and A I've ever heard on sleep imaginable.

I was super impressed with the questions that came in from people I couldn't resist but sprinkling in a few of my own questions. And many of my team did the same thing and we had a hard stop imposed by his flight departure, and that forced us to just be ruthlessly efficient and accomplish a lot. We actually got through about 80% of what I thought would take probably six hours. So as a quick refresher. Matthew is a professor of neuroscience and psychology at Cal Berkeley. He's the founder and director of the Center of Human Sleep Science. He's earned his degree in neuroscience from Nottingham University in the UK, his PhD in London before becoming a professor at Harvard and ultimately moving to Berkeley. You may know him more from being the international bestselling author of the book Why We Sleep. He has also very recently given a Ted talk that was incredibly well received this year at the conference, and we will link to that, of course, as reminder, of course, am maser for subscribers only.

So if you're not a subscriber, you'll only be able to listen to a little bit of this episode. But hopefully, episodes like this and all of the other A Emma's and benefits will at least convince you of the benefits of supporting our work here in an ad free environment. And you can do that at peter T MD dot com. Forwards Last subscribe. In this episode, we talk about a Thanh of stuff, so the questions dive in with How do we get the best about asleep? How do we specifically go about targeting different stages of sleep? We talk a lot about what it means to create the perfect sleep environment. So if the first episodes that we did with Matt focused a lot on why you want to sleep this, we focused much more today on how you want to sleep. Timing of sleep, with respect of food, exercise What is a wind down routine?

Look like? Sound temperature light. All of these things we got really deep on supplements, melatonin, CBD. We talked about GHB. Th see all of these things. We went into strategies for what to do when you blow it. We all do. We have a horrible night of sleep. What can you do about that? This was something that, actually I found very helpful. Personally, what can you do to help your kids? Unfortunately,

kids are often in an environment educationally that is actually not in the best interest of their school. So, you know, one of the best takeaways from this entire episode was What can you do is apparent to make it better for your kid If you don't have the luxury of simply moving them to a school that has a better sleep strategy, it would take me another 10 minutes to go into, even at the topic level, what we talked about. So you have to take my word for it. This was a great episode totally worth your while. And without further delay, I'd love to welcome you to my discussion as a follow up with Professor Matthew Walker. thank you so much for coming all the way down to San Diego to answer everybody's questions on sleep Pleasure for the sake of time, because we're gonna try to do this in under three hours. I won't get to ask you how much fun you had last night in the simulator, but I think in a word, it looked like it was pretty fun, extra ordinary. Maybe we can convince you to do monthly AM A's. If we throw in the simulator,

I mean either or are condemned for simulator or AM A or both. But it's a pleasure to be back and thank you again for having me and

hosting me here. Yeah, yeah, well, this is kind of a first. I know we have never done it. Where we've taken someone who's been on before, is a guest and then brought them back. Specifically, Graham and Tim has done stuff like this in the past. It's been quite popular. I think it's safe to say that your three episodes probably generated more questions than any other topic we've covered. And I think that's why we realized this was important thing to do. And I know how passionate you are about this. In fact, in the interim, since we did our first interview and this one,

you giving a Ted talk and I think it just came out, right? Yeah, it just came at will be sure to link to that. That's a tough talk to give, huh? That's pretty intimidating.

It was a lot of fun, but it was work to being a professor, you know, lecture of most weeks. So you think that you know what you're doing? Ted is different. It has a special aura around it, and then they have ah, particular sort of style that they would like. So it was something different. But I like that because it stretches you. Just when you think you're starting to perfect a craft, you realize that there's something else left. And to me, it's the difference between being an exceptional public speaker and then being speaker, who has wonderment. And I would rank people like Carl Sagan,

Richard Feinman and then probably Sir Ken Robinson, who's done some fantastic Ted talks. They transcend being an exquisite public speaker into being someone who is just so compelling because they add this Sprinkle layer on top called wonderment, And I've yet to ascend that pinnacle of wonderment in my public speaking capacity. I'm getting a little better, but I'll never hit their perfection.

Yeah, that's an interesting way to put it. I've heard all of them speak, Of course. In fact, Robinson's talk on education is probably the second or third. At least. The last time I ever looked was probably one of the the five most viewed Ted talks.

That's right. On what? Both

from Liverpool. It? Yeah, yeah, I gotta watch it over and over again. I think you guys have the accent advantage. By the way. I just think like I can listen the accent all day long. So we've got questions, some of them that are kind of high level, some of them that air super nerdy. And we're gonna get through. I think all of these and you've I know we haven't imposed hard stop so you can get a flight back home. Otherwise, I realized this would take easily six hours. So we'll get through it. We can,

in whatever we can't get through. Maybe, You know, you offered to graciously just take a microphone and start recording stuff, which I think people will lap up.

I will keep being a repeat offender on this show for his longest. You and the listeners have me.

Yeah. So let's start with some of the sort of high level questions, right? So this was posed by a reader. So for a healthy adult, he wants to optimize their sleep and is willing to do everything they can to get the A plus effort gun to the head pick of flawless sleep set up for an unknown, healthy adult using the intuition you have built. And so we've talked about some of these things, but how much time should they be sleeping? How consistently do you want to see them hitting Deep Sleeper asleep. And you know, now that I think about it, before we ask this question, many of these questions come through the lens of people using devices like Aura, woop Fitbit. Probably the apple watch has something comparable. What I heard you say in our last discussion, waas. Those devices are probably pretty good at estimating duration of sleep, probably less good at estimating stage of sleep. Is that a fair

assessment? I think it is right now, and especially the segregation between sort of rapid eye movement and non rapid eye movement. You can think of it as a sort of like a three step level total sleep time. Are you awake or you're asleep. Essentially, that's kind of like a two class algorithm. Wake sleep, and they're pretty good at that. Step down. Then you can do a three class algorithm. Are you awake? You in non rem sleep or you in REM sleep and they're pretty good at that four class model is Are you awake? Are you on light? Non rem sleep? Are you in deep non rem sleep? Or are you in REM sleep?

That's where they sort of fail. And that's where something like my sleep laboratory continues to be the gold standard. So somewhere between sort of a two class model and a three class model, that's where those devices right now are sort of rate limited, so I wouldn't get too nervous about some of your sort of deep sleep versus light sleep numbers. Some of them could be accurate within an individual, but for others it can be more tricky because of their physiology. That's not giving the right signals for class accuracy. Yeah, And what about

the relative changes? I mean, this is sort of the way I explain things to my patients, which is probably There's no question I get asked more than Peter. Why is my deep sleep only 17 minutes a night should be an hour and 1/2 to which I don't have a great answer other than let's not assume that that's necessarily the case. It maybe it might not be and must. We did a poly song. I don't think we can know. But what about relative changes? So the most obvious example is alcohol, which we've talked about. There's no doubt that alcohol impacts the model that's right in the wrong direction, which gives you some confidence that the model is at least picking up a signal that makes sense.

This is a great point, which is overall from one individual to the next. It may be somewhat inaccurate for that real declassification of various stages of sleep, but within an individual from one night to the next, it may be routine, the inaccurate meaning that once you establish some kind of baseline and you see a deviation from that baseline, it's more than likely that that deviation is a real deviation rather than a problem of the technology. Because the technology, even though it's a riffle, is consistently a raffle night after night after night and to any variants from that, you're absolutely right. That's probably where you want to focus more of your

attention. Yeah, so what? I try and again please tell me if you disagree, what I try to get people to think about is it? Once you've had these rings or whatever for a few months, you pretty much have a sense of what your baseline is on. Deep sleep, light sleep, ram, time in bed, etcetera. Don't judge those numbers. Now. Judge yourself against relative changes from those numbers.

Absolutely. So. The way I think about this is don't follow headlines follow weekly trendlines. That's the way that you should really sort of think about this type of data said. Now I can follow headlines in my sleep laboratory because we have that degree of precision and accuracy. But when it comes to these trackers and I were them, too, and I'd love the AP eyes just data hungry, downloaded, I will plot all sorts of those trends But it's the trends to follow, not those sort of daily headlines. Try not to be too worried except when you see a marked deviation away from the trend line and you think that you can pinpoint the cause. Alcohol, great demonstration, jetlag. Perfect demonstration, etcetera, etcetera. So that's how

you can see it. Yeah. Yeah. I also tell patients they're much better at measuring the raw inputs because, at least for aura, which is the one that I can speak to, cause I know the most about it. I mean, they're very good at measuring heart rate, heart rate, variability, temperature movement and those things matter. When you're resting, heart rate is up seven beats per minute and your heart rate variability is down 20%. Yeah, that's gonna impact the algorithm negatively. And whether or not the fidelity with which its prediction is perfect,

we don't know, But those are bad things. Your heart rate shouldn't be up. 10 beats and your bravery Lucien get crushed. And as you said, I don't think I've ever seen those things where I couldn't point to the Y. The room was boiling hot, ate a monster meal 10 minutes before bed I had two drinks or more. Those the things that sort of consistently do it, which actually now brings us back to our questions. What is the optimal time to stop eating before

bed? So I would say, probably about three hours before bed is where I would really cut it off on. The principal reason is just because when you lie down more likely to get acid reflux more likely to have digestive issues. That's the first principle reason a lot of people will just get reflux if they eat too much closer to bad time. The other reason, however, is to be mindful of core body temperature. So the advice generally is. Don't go to bed too full. Don't go to bed too hungry. And if you do feel as though you ate earlier in the evening and you just need something to take the edge off, try to stay away from sort of simple carbs. The reason being is that those, well, actually just get translated more quickly into a sort of an energy and ultimately, a heat index on when you need to fall asleep,

you need to drop your corporate temperature. So if you're fueling yourself with simple carbs right before bed. Let's say that you just have a nice big bowl of cereal. Sugary sort of nonsense. You will actually see a slight increase in corporate e temperature because of that sort of sugar caloric burning that raises corporal temperature that makes it harder for you to fall asleep. Why? Because you need to drop your core pretty temperature by about 2 to 3 degrees Fahrenheit to initiate sleep. Amend to stay asleep, and that's the reason you'll always find it easier to fall asleep in that room that's too cold and too hot. So that's the second reason that I would say, Try toe back away from food. If you do need to eat, try to maybe lean more towards protein if you can run away from simple sugars just before bed. But for the most part, cut off about three

hours, okay? And I want to come back to temperature in a moment with sleep environment. But let's go to another question, which is the same question. But with respect to exercise, we certainly learned in our first discussion that exercise has many benefits, but Visa VI sleep, it generates more Dennis ng and a dentist. Singh is one of these three pillars that creates this drive for sleep. But can it backfire if you exercise too close to

bed? We think it can. I mean, the evidence, I would say, is moderate to strong on the following reasons. Firstly, you actually get an increase in corporate temperature, of course, and then you get this nice sort of down shoot sort of later on, and that's good. But if you're exercising, let's say in the last two hours before bed, your core body temperature, depending on what you've done, may still be too high and working against what it would normally like to do from a circadian perspective, which is start to drop down and low you into sleep by sort of evacuating the core temperature from your body.

So be a little bit careful with exercise to Costa, but I would say a cut off of about two hours. The other reason is not just temperature, though, but also a whole cascade of hormones. You can typically get epinephrine nor epinephrine or adrenaline or adrenaline. The headquarters all is well. I'm sure horses all usually has a time decay of exercising again. It depends on what you're doing, of course, but sort of somewhere between 90 to 120 minutes. So those things can actually work against you in terms of sleep. But for the most part, exercise and I think that is before two hours of sleep is a fantastic tool in terms of sleep promotion. What I would say, though,

is that the data in the opposite direction is even more powerful, and I think we chatted a little bit about this. It's not just that exercise helps sleep, sleep profoundly helps exercise, and in fact, that is a two way street. But if the traffic is flowing more dominantly, I would argue the evidence is that sleep is better for exercise and they're both reciprocally beneficial on. What we know is that when you're sleeping well, firstly, just your motivation to do anything and especially exercise is increased dramatically to forget. And I think they're after the likelihood that you're going to get into the gym, get out on the bike, get out in the road and start pounding the pavement far higher. When you've slept well, they're after.

It's great. Peak muscle strength increases your ability to respond. I wr and expel Carbon dioxide is improved. The more sleep that you're getting, likelihood of injury risk markedly decreased. Your ability to even sweat and perspire is determined by how much sleep that you get, and we sometimes forget how critical perspiration is for optimal exercise. So it's just a peek, muscle strength, all of those things. It's just this cascade of benefit that you get from sleep from the point of getting out of bed getting started and then, once you get started exactly what your performance will be, including time to physical exhaustion, which we mentioned last time. Too beautiful relationship between those two.

Yeah, two nights ago, I flew back from New York, and I almost always take the morning flight back because one, you're more productive on the airplane. It's just the morning there's a far less chance of delay on the first flight out of New York than the last flight out, but occasionally just whatever the schedule. And so I had to do what I hate doing, which is take the eight PM flight from JFK back and, as is the case, at least 50% of the time crew shows up late, but time the crew gets there An hour and 1/2 later, you're number 317 on the runway. I mean, we didn't get back until, like, two and 1/2 hours later than planned.

So and I have a pretty fixed wake up time, just both because of the jet lag coming back, but also the kids. So I woke up yesterday morning only having five hours of sleep, which was, I think, good, all things considered. But it's less than what I've now become accustomed to. It's interesting you say this because I worked out in the morning and my wife asked me later in the day she's like, How was your work? And I was like, I gotta tell you, it was miserable not for any other reason that I didn't want to even be in the gym. It was like two hours of how quickly can I be done with this? I just don't want to be here. For what it's worth, I didn't perform well either, but what caught my attention was how little I wanted to be in

the gym. If that's not bad enough, what you also dio is get a compounding set of problems, a top of that which is your appetite. And I think there was a question that maybe I can try to weave in here, which is when you are sleep deprived. Essentially, what the brain receives is a signal that is not dissimilar to starvation, and it releases a cascade of hormones that change your appetite profile. You want to eat more and you're less satisfied with your food. Why is this? The reason is the following, and we've mentioned it before, I think briefly, human beings seem to be the only species that will deliberately deprive themselves of sleep for no apparent reason. Only other time that we see this in the wild, where it does seem to have an impact,

is when animals are under conditions of starvation. When you get a starvation signal, it usually is the cause of saying you need to forage in a larger perimeter area for you to survive, and the way that you're going to do that is probably to stay awake for longer hours so you can forage further. So what happens when the body undergoes sleep deprivation is that the brain thinks, Oh I must be under conditions of starvation. From an evolutionary perspective, the only time I'm ever sleep deprived is when I am starving when I'm under conditions of starvation. Now, human beings, when they sleep, deprived themselves. They're not under conditions of starvation, so it's a fake starvation signal. So when you're deprived, your brain thinks,

Oh my goodness, I must be under starvation. It increases ah hormone called ghrelin, which makes you want to eat Maur. It suppresses a hormone called leptin, which says you're satisfied with your food. Don't eat more so overall hunger levels go up. You start to eat more. Now we combine that with this lack of motivation of exercise in all sorts of obese, a genic directive territory eating more, wanting to exercise less You're burning fewer calories That usually is. Why was starting to understand part of the sleep dependent obese, a genic equation

and the other hormone that plays? I think at least for me, an increasingly greater and greater role in that cascade is cortisol because of its role directly on the out of post site. It is a very anabolic hormone to adipose tissue and Avery Cata Bolic hormone to muscle tissue, but also its effect on the liver and glycogen stores via a paddock glucose output. So it's raising glucose, which in turn is raising insulin, which is now acting alongside cortisol. I mean, it seems intuitive to me, but I don't know what the evidence is that sleep deprivation would tend to also run with hyper. Korda, Salim Mia We can see why hyper Korda Salim Mia would drive sleep deprivation. Do we think that there's a feedback loop that is in the wrong direction? E. The Maur Sleep deprivation you have, the more court us all that the animal or human tends to

produce. That's exactly what we see. Typically, yeah, And if you can go into that state chronically, which is what most of society is not pulling all nighters. Most of society is chronically under slept. So what you end up doing is having this kind of chronic, mid toe, high level of hyper course easily mia. And that is leading to all of this cascade of biology that is non optimal, part of which is a collection of changes not just in the brain but also in the body to that cortisol spike can actually lead to things like anxiety and what you should not have if you're looking for good. Sleep is a high level of quarters on, and so it's bi directional that the less that you're sleeping, the higher that cortisol level. If that cortisol level stays high at night, it's very difficult to get the good sleep that you need, and so

on and so forth. And that might also be evolutionary, right? It might be that when the animal is sleep deprived, the evolutionary trigger is there's a reason you're sleep deprived. You will need more Courtis. All that's right. I had this discussion with Robert Sapolsky, where we went into great detail about the role of cortisol in the sub acute level of stress, which is actually for many people, not the stress were under. But evolution doesn't know the difference,

right? Yeah, we've imposed sort of the mental sabertooth tiger, which is called society. Trickett Anxiety.

I should put fangs on my phone. You know, it's nothing more than a collection of electronics, and yet it induces in me the same feeling as a sabre tooth tiger would if it were just growling around me from 100 yards away in perpetuity.

Yeah, and just like that, you have night shift on your iPhone. There's fangs during the day. Should switch to a sign with a lots of disease and then a big strike against them over because that's essentially what it's gonna do to your sleep

as well. Well, let's talk a little bit about the wind down routine. Then that's a nice foray into that. So I think anybody listening to this who was obviously so curious about sleep has thought about this idea of Okay, you've made a very compelling case in our first discussion that if you want to sit there on your phone, glued to your phone in bed until you put it down, that's just a recipe for disaster. So we accept the fact that we've got to get the electronics out of the way because of two reasons. At least write. The blue light itself is damaging, and it prevents the pineal gland from getting ready to give us that surge of melatonin. But also there's kind of an emotional piece of that as well. So if you were giving somebody advice on the perfect wine down routine and this is a real person. So this isn't someone who has the luxury of being on a meditation retreat their whole life. This is someone who has a job. This is someone who has a boss.

This is someone who is still accountable and lives in a world that, unfortunately, demands paying attention to their phone. But they're committed to getting the best sleep they can. How would you counsel them at 6 p.m. They just finished dinner for 6 30 Whatever. What should they be doing between now and say 9 30? Everyone hope you enjoyed a sneak peek this am a A maze, along with extensive show notes and member only. Discounts on products that I think are awesome are available to subscribers own. So if you're interested in hearing the remainder of this A. M A. We want to access any other benefits that come with being a subscriber. Please head over to Peter tia MD dot com forward slash Subscribe to learn more and sign up. You can find all of this information and Maura Peter tia MD dot com forward slash podcast There, you'll find the show notes, readings and links related to this episode You can also find my blogged at peter.

Tia MD dot com. Maybe the simplest thing to do is to sign up for my subjectively non lame once a week email where I'll update you on what I've been up to. The most interesting papers I've read and all things related to longevity. Science, performance, sleep, etcetera on social. You confine me on Twitter, Instagram and Facebook, all with the I d Peter A T f M d. But usually Twitter is the best way to reach me to share your questions and comments. Now for the obligatory disclaimer this podcast is for general informational purposes only does not constitute the practice of medicine, nursing or other professional health care. Service is including the giving of medical advice and note. No doctor patient relationship is for use of this information, and the materials linked to the podcast is that users own risk.

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