In this episode we discuss:
- How Dr. Walker Becomes a Sleep Researcher
- What did we learn about sleep
- How our sleep patterns have changed
- Tracking your sleep
- Owl and Lark Sleep Patterns
- How Doze, Meditation, and Medications Affect Sleep
- Five things you can do to improve your sleep
Hi everyone, this is Chris Kresser. Welcome to another episode Radio Health RevolutionThis week I am very pleased to welcome Dr. Matthew Walker as a guest on the show. Dr. Walker is an English scientist and professor of neurobiology and psychology at the University of California at Berkeley, my alma mater. His studies are devoted to the effect of sleep on human health and his illness. He was previously a professor of psychiatry at Harvard Medical School. He is also the founder and director Center for Human Sleep Science,
He has received numerous funding awards from the National Science Foundation and the National Institute of Health and is a member of the Cavley National Academy of Sciences. He has published over 100 scientific studies and has been featured on numerous television and radio stations, including 60 minutes, Amanpur and Company, National Geography, NOVA scienceNOW, Joe Rogan's Experience, NPR, Peter Attia Driveand the BBC.
I really look forward to talking with Matt, because he really is the main expert in the world right now, I think when it comes to sleep, why we sleep, what sleep does for us, what happens when we don't sleep and what we can do to improve our sleep. I look forward to this conversation and hope you enjoy it. Let's dive in.
Chris Kresser: Dr. Walker, thank you very much for being here. I really looked forward to it.
Matthew Walker: It is an admiration and pleasure to be here, Chris.
Chris Kresser: So, I would always like to start with a small background. Can you tell us how you became interested in studying sleep in the first place?
How Dr. Walker Becomes a Sleep Researcher
Matthew Walker: Yes, I think it is interesting. I don’t think that someone, when he grows up, wants to become a sleep researcher. When you think about this classroom of young children, and they say: “Who would you like to be when you grow up?” And your hands heave, astronauts, doctor. No one speaks of the sleep of a scientist.
Chris Kresser: Yes, I can’t remember anyone saying this in my class.
Matthew Walker: And they must change this at some point. But I think that for me, perhaps, like for most people, I became an occasional sleep researcher. I started at medical school what you can do at the age of 18 in the United Kingdom. After a couple of years, one of the professors took me aside and said: “Look, you always ask questions, and you are not doing this for the wrong reasons. You do this for the right reasons. But doctors are probably more interested in answers than in questions. Therefore, I think that you can actually be a scientist, not a doctor. ” And so, this was a time when we did not have programs for doctors and doctors of sciences. It was a one-track mentality.
So I switched to neurology, the science of the brain. As for my doctoral dissertation, I studied brain wave patterns in people with very early signs of dementia. And we tried to use these brainwave recordings to differentially diagnose what type of dementia they had, such as vascular dementia, Alzheimer's dementia, or Parkinson's disease. And I failed miserably. I did not get good data. And every weekend I ended up Friday at the libraries and took all my medical journals home to my doctor’s residence. I had a small igloo in my journal room on which I sat on the weekend reading. And one weekend, I realized that these different types of dementia, some of them will be in the centers that give rise to sleep, and others not. And I thought, my goodness, maybe I’m recording my patients’s sleep at the wrong time when they weren’t sleeping, I had to measure them while they were sleeping.
And I received a small grant, created a sleep laboratory, did not know what I was doing for the first couple of months, figured it out. And then excellent results came. At this point, I started asking the question: I wonder if sleep is a symptom of degenerative dementia. Interestingly, this is a predisposing risk factor or causal trigger. And then I thought, oh god, so what is this thing called sleep? I realized that no one could answer a simple question then, which was 20 years ago, which was "Why are we sleeping?" And I thought, well, this is a great question. I will go and answer this in a couple of years and return to this question, not realizing that some of the most insightful minds over the centuries have not been able to crack this question.
And I thought that without any pride I was going to do it in two years. And that was 20 years ago. And I think that I learned that difficult questions care little about who asks them. They measure their complexity lessons anyway. And I was trained. So this was my chance trip to sleep.
Chris Kresser: Wonderful. What a helpful mentor you had in this process.
Matthew Walker: Even more. Tough love all the way.
Chris Kresser: Yes, yes. Do you think you could go through the MD / PhD program if they existed at that time, 20/20 retroactively?
Matthew Walker: Even more. Yes. I think what I like about science is that it is incredibly intellectually useful. But emotionally, academic life, in a sense, is perhaps a little devoid of emotional satisfaction. Because it is almost selfish. What grants do you receive? What podcasts are you on?
Chris Kresser: Correctly. Where do you post?
Matthew Walker: What books, yes, where do you publish? What awards have you won? And this is not very, for me, at least personally, it was not very satisfying. And where I get my emotional nutrition from is actually a teaching. I love to learn. Here at the University of California at Berkeley, I teach a large class in sleep science. And there it is not in me, but in my students. And it is very without ego, and you cannot have ego in this regard. Not if you want to be a good teacher.
Chris Kresser: Right, right. By the way, we are neighbors. I'm in North Berkeley Hills. And I did my student at the University of California at Berkeley.
Matthew Walker: Indeed? Good. Was your undergraduate in?
Chris Kresser: Berkeley, being Berkeley, I came up with for myself. So, I wrote my dissertation on the social and cultural consequences of the Internet, which was just starting to develop. You and I are about the same age. So it was from 92 to 96.
Matthew Walker: Oh my god, you are prophetic.
Chris Kresser: Well, the World Wide Web was like gray background pages with blue links, do you remember that? And my claim to fame was that I had a photo on my site that was pretty, pretty fashionable.
Matthew Walker: Yes, I remember something like Internet communications, which were the forerunners of email and work in terminals and scripts.
Chris Kresser: Right, right. Exactly. So, you are teaching a great course at Berkeley.
Matthew Walker: I do.
Chris Kresser: Wow, this is phenomenal.
Matthew Walker: Yes, it's called the Science of Sleep. This is about 500 or 600 children.
Chris Kresser: Oh, I love that. It's great, I remember these courses. I'm sure they like it.
Matthew Walker: Such a privilege
What did we learn about sleep
Chris Kresser: Let's talk a little bit, you mentioned, of course, I remember the time when the question “Why are we sleeping?” Was a mystery. And no one really understood the answer. So what have we learned over the past 20 years about how people are attached to biological sleep? Why do we sleep in the first place? And then I am also curious to find out if the answer to this question has changed as we moved from our hunter-gatherer roots to the development of agriculture, and then to industrialization and, more recently, the appearance of screens and other technologies that violated our circadian rhythm? Of course, the most recent is too fast for genetic evolution, but perhaps these are not epigenetic changes. So I'm interested in this whole trajectory.
Matthew Walker: Yes, great questions. Let me try to flip the coil. I think the first question is why are we sleeping? And we did not have a good answer 20 years ago. The rude answer was that we sleep to cure drowsiness, which is the stupid equivalent of what we eat to cure hunger.
Chris Kresser: Ontological argument.
Matthew Walker: Yes Yes. This does not tell me anything about the nutritional benefits of nutrition and food, and so on. But now, after a wonderful series of studies over the past quarter century, we were actually forced to turn the question around and ask: “Is there anything that does not give sleep in terms of functional benefits for both the brain and the body? ? "And it was a real fight. We found that most of all tissues and physiological systems in the body, as well as most of the operations of the mind, improve greatly when we get enough sleep, and obviously get worse when we are short. Therefore, I think this is a radical change of events.
I think, turning to your question about sleep as a function of evolution for people, I think that the question of the evolution of sleep is interesting for at least two reasons. Firstly, if you take a step back, this is the most idiotic of all species of biological species. Because, firstly,
Chris Kresser: This is dangerous, right?
Matthew Walker: Yes, you do not find food, you do not breed, you do not find a partner, you do not care about your children, and, worst of all, you are vulnerable to predation.
Chris Kresser: Yes.
Matthew Walker: So, on any of these foundations, and especially at all collective levels, Mother Nature should have resolutely opposed what is called a dream. In other words, if a dream does not support an absolutely vital set of functions, this will be the biggest mistake that an evolutionary process has ever made. Now we understand that this was not a mistake. It was a sublime brilliant move. But the second reason, I think this question is interesting, perhaps because the dream did not evolveWe assume that this is so.
And I have a stupid theory that I think will be very difficult to prove. And I'm sure that maybe I'm wrong. But I have an idea that, in fact, we started to sleep. And it was from sleep that wakefulness arose. Why do we assume that the footprint was a predecessor, and then we must develop what is called a dream? I think we started to sleep, and from this wakefulness arose. And waking in many ways is surprisingly harmful. If you look at the brain, it’s pretty clear in terms of metabolism, wakefulness is low level brain damage. And so I think that we had to return to sleep every time we woke up.
So, in a sense, I hardly think that the dream developed from the point of view of the starting point. But then the dream developed sharply in different species. It seems that every species studied by us is sleeping. Even very old, evolutionary, ancient earthworms. In fact, bacteria even have active and passive phases, which are possibly precursors to sleep and wakefulness. And from that moment the dream broke, heroically at every step of the evolutionary path. How could it be, if it was so well preserved, how could it not be significant?
Chris Kresser: Yes, that makes a lot of sense to me. And I like your investigation of this issue and the way you changed it. Because sometimes it is there that the greatest ideas come.
Matthew Walker: Or the most idiotic of them. We'll see.
Chris Kresser: Yes, let's see. So, let's talk a little bit about what happens when we sleep, especially from a physiological point of view.
How much sleep do you need? Can a dream take a nap? Is there any difference between owls and larks? Check out this RHR episode to find answers to these questions, and learn five things you can do to improve your jokes. #healthylifestyle # chriskresser
How our sleep patterns have changed
Matthew Walker: Yes, and, in fact, I realized that I did not answer the second part of your question, which was about how the dream changed.
Chris Kresser: That has changed, yes.
Matthew Walker: Yes. Gosh, that's a great question. So yes, that seems to have changed when we moved from a sort of hunter-gatherer to an agrarian revolution, then an industrial revolution, and now we are in a digital revolution. If you go back and study some of these tribes that we made, these hunter-gatherer tribes, whose lifestyle has not changed for millennia, I think the following two important messages about the dream are as follows. At first, they don’t sleep the way we are in terms of timingIn other words, have you ever wondered what the term "midnight" really means?
Chris Kresser: The middle of the night.
Matthew Walker: Midnight, it’s true that for us, midnight in this modern age is usually the last time we check email.
Chris Kresser: Bedtime.
Matthew Walker: Yes, before going to bed. But actually, if you look at these tribes of hunter-gatherers, this is really the middle of their night. Usually they go to bed a couple of hours after sunset, this is their midpoint of sleep. And then they usually begin to rise a little before dawn. Usually they rise with a change in temperature, not with the sun. Thus, it is the temperature that seems to help us wake up better than the light itself, although light has this function.
So, firstly, the way they place their sleep on the dial is different from what we do in the modern world. The second way is the phases of sleep. They usually have what is called biphasic sleepIn the countries of the first world we do single phase sleepWe sleep in one fight all night. We hope that we try to get from eight to nine hours. They do not do this. Usually they sleep somewhere between six and a half to seven at night. And then, in the afternoon, they usually took a nap, like a siesta, to make up for the remaining eight-hour average need, which all people seem to need. So I think this is one of the implementations.
Now, moving on to the timeline of human evolution, we saw strange behavior. It was more like the Dickensian era, when people had such a thing as the first dream and the second dream, where they slept for about four hours, and then woke up in the middle of the night, chatted, wrote music. , eat, drink, make love. And then they came back and slept the so-called. This happened? It seems from the letters, historically. Is it physiologically the way we were designed to sleep? No, there is no good biology that tells us this. It was probably a social propaganda of sleep, not a biological decree.
Chris Kresser: I have patients who read about it online. And I asked them about their sleep patterns. They tell me they are doing biphasic sleep. And I rummaged around a bit and found that they wake up at three in the morning, at two in the morning, send emails and roam the network. And then I asked them: “Okay, okay, you also go to bed at eight o’clock in the evening, what is part of this whole equation?” No, don't do that. So yes, it seems, even if it was typical in a certain period of time, this does not mean that it is normal for people or useful for human physiology.
Matthew Walker: Yes. And I think this is very clear to the public when they hear it, that this is a common practice. Well, ok, that's how we should, so we slept. But, of course, the timing Homo sapiensIt goes much further than that. And if you look, we did not sleep.
Chris Kresser: Yes. Therefore, I want to return to what happens physiologically with sleep. But you mentioned something that, I am sure, has poured into the ears of several people: that all people or most people who are actually part of the question need eight hours. And you mentioned eight to nine hours. So this is obviously one of the most frequently asked questions. how much do i need to sleep? So, this is the first part, and the second part – how do you know if there is a range for people? How do you know where you are in this range?
Matthew Walker: Yes, two great questions. So, firstly, we know that the number of people who can survive for seven hours of sleep or less without showing any biological or cognitive impairment, rounded to the nearest whole number and expressed as a percentage of the population, is actually zero.
Chris Kresser: Wow wow.
Matthew Walker: And I think that some people will be taken by surprise because they have heard of this kind of short, this choice of people who have this kind of short sleeping gene. And we know this gene, it's called Dec2 gene. And when I describe this short-sleeping gene, as it were, many people think: "Oh, I think I can be one of them."
Chris Kresser: Of course.
Matthew Walker: This is part of the population. По статистике, у вас гораздо больше шансов быть пораженным молнией, чем иметь этот ген, просто к сведению. И, кстати, они не спят пять часов. Если вы посмотрите на данные, если вы принесете их в лабораторию и скажете: «Просто дайте им поспать», вы заберете все циферблаты, полная темнота в лаборатории, и они не поймут. Это просто: «Каково их привычное естественное выражение сна?» В среднем, они успокаиваются около шести с четвертью часа. Таким образом, генетический коротко спящий мутант спит шесть с четвертью часа. Это самая короткая переменная сна. И, конечно же, для большинства людей мы знаем из опросов, что средний взрослый американец спит около шести часов и 31 минуты.
Крис Крессер: Правильно.
Мэтью Уокер: И они не генетический мутант.
Крис Крессер: Not. А треть американцев спят меньше шести часов.
Мэтью Уокер: Правильный. Так что это в среднем. Да, и ваша точка зрения элегантна. Если вы думаете об этом распределении, большая часть, в конце этого, определенно намного меньше, чем это.
Крис Крессер: Как будто все думают, что они феноменальный водитель, или когда появляются опросы, это все потрясающий драйвер. Они невероятные любовники.
Мэтью Уокер: Это верно. Я считаю, что это был Стерлинг, я сам одержим гонщиком. И поэтому я думаю, что это было то, что сказал Стирлинг Мосс, известный британский гонщик: «Все люди думают, что они тоже отличные пилоты и замечательные партнеры».
Крис Крессер: Это верно. Это верно. И мы все думаем, что у нас короткие шпалы, верно?
Мэтью Уокер: В точку.
Крис Крессер: Мы мутанты сна.
Мэтью Уокер: Да, напротив,
Крис Крессер: Но вы скорее поражены молнией, чем кем-то с этим геном. И даже в этом случае требуется уровень сна, который не обеспечивают 35% американцев.
Мэтью Уокер: Это верно. И мы также, кстати, не знаем, что это за сон, который они получают. Мы не обязательно знаем, означает ли это, что у них более короткая продолжительность жизни. Потому что мы только что обнаружили это генетическое изменение. У нас не было возможности отследить этих людей, мы действительно не знаем. Их слишком мало, чтобы получить какие-то хорошие данные, чтобы сказать с метаболической точки зрения, является ли их глюкозная регуляция хуже или сердечно-сосудистая, чаще ли они страдают гипертонией или у них высокий риск развития рака? Мы на самом деле просто не знаем. Так что да, они могут спать меньше, но означает ли это, что они выживают так же долго, как в продолжительности жизни, так и в период здоровья? Мы понятия не имеем.
Крис Крессер: Правильно.
Мэтью Уокер: Так что это еще одно предположение.
Крис Крессер: Я также читал некоторые исследования, я уверен, что вы можете рассказать нам об этом, что существует разница между субъективными и объективными нарушениями сна. Так что когда люди лишенный снаПервоначально они будут сообщать о субъективных изменениях в своих, в различных компетенциях. Другими словами, они замечают, что они лишены сна, и это влияет на их работоспособность, их познание и т. Д.
Но после некоторого периода адаптации они перестают осознавать, что их производительность ухудшается, хотя с помощью объективных мер можно четко продемонстрировать, что это так. И это приводит к другой проблеме, когда люди думают: «Эй, я в порядке. Я сплю шесть или пять часов, но это никак не влияет на меня ».
Мэтью Уокер: Это одна из больших опасностей со сном в том, что вы не знаете, что лишены сна, когда вы лишены сна, Таким образом, ваше субъективное ощущение того, насколько хорошо вы делаете, является жалким показателем того, насколько хорошо вы делаете. По аналогии с пьяным водителем в баре. У них было семь или восемь выстрелов и пара пива.
Крис Крессер: "Я в порядке."
Мэтью Уокер: Они берут ключи и говорят: «Я в порядке, когда еду домой». А вы отвечаете: «Нет, субъективно, я знаю, что вы думаете, что вы можете ехать домой, но объективно, нет». И то же самое верно с недостатком сна. И это, я думаю, одна из реальных составляющих этого. Отличным примером этого, клиническим примером, также является нарушение сна, называемое апноэ во сне, когда у вас сильный храп. И это очень, это очень постепенный переход к дефициту сна.
Таким образом, почти через несколько лет у вас развивается настоящее хроническое ограничение сна. И люди с этим расстройством, большинство из них не диагностированы и не лечатся. Они просто думают, что это я в этом возрасте. Это то, как я, это то, как моя производительность. Но когда вы лечите их, показатели их здоровья заметно меняются в лучшую сторону. И они просто не понимают, насколько хорошо они могли себя чувствовать после восстановления сна. И я думаю, что это отличный клинический пример этого. Пациент однажды сказал мне, что как будто кто-то вытирал туманное стекло, и, наконец, я смог увидеть мир сравнительно. И это радикальная трансформация. Я думаю, что это то, что многие люди испытывают прямо сейчас. У них хроническая задолженность по сну, и они действительно не знают, насколько хороши их психические и физические версии, они могли бы быть, если бы спали достаточно.
Я думаю, что это касается вашего второго вопроса: «Как мы узнаем, сколько сна нам нужно?» Я думаю, что первый и очевидный вопрос или ответ, извините, был бы на вопрос, если бы вы не задали тревога, ты будешь спать дальше своей тревоги? И если ответ – да, значит, вы не высыпаетесь. Ваше тело и мозг еще не закончили со сном, и вам явно нужно больше. Теперь это одна хорошая метрика. Это не означает, однако, что для некоторых людей, страдающих бессонницей из-за поддержания сна, когда они просыпаются всю ночь или у них возникают неудачные ранние утренние пробуждения, это не означает, что они хорошо спали. Так что это не полный вид чисто диагностического теста. Но для многих это очень хороший показатель. Каков диапазон сна? Мы видим диапазон в общей численности населения от семи до девяти часов общего времени сна. И я подчеркиваю «время», потому что время не время в постели. Я часто говорю, что вам нужно спать от восьми до девяти с половиной часов, чтобы спать от семи до девяти часов. Поскольку большинство людей, выключая свет, они не сразу засыпают, а затем остаются спать всю ночь. Это называется ваш эффективность сна,
Другими словами, из общего количества времени, в течение которого вы лежите в постели, какой процент этого времени спал и каков ваш процент эффективности сна. И если вы здоровы, у вас обычно эффективность сна выше 85 процентов, надеюсь, немного лучше. Теперь, если вы подумаете о восьмичасовом ночном сне, который, если я сделаю математику, я сделаю неправильно, но это может быть 440 минут, и вы думаете, что у вас эффективность сна на 90 процентов, это означает что вы будете бодрствовать в течение 44 минут всю ночь. Так что для того, чтобы вы получили свои восемь часов, вам действительно нужно быть в постели восемь часов и 44 минуты.
И люди делают эту ошибку, когда слышат, как такие ученые, как я, говорят: «О, тебе нужно семь-девять часов сна», они думают, что в постели семь-девять часов. Поэтому, если я ложусь спать в течение семи часов, у вас, вероятно, будет гораздо больше шансов заснуть около шести с половиной часов, если не меньше. Так что, я думаю, что это действительно важный момент для людей, которого они обычно не осознают, потому что такие ученые, как я, не очень хорошо объясняют это.
Крис Крессер: Такие важные моменты, и я думаю, что многие, вероятно, сейчас сходят с ума, слушая это.
Мэтью Уокер: Пожалуйста.
Крис Крессер: Но это хорошо. Я имею в виду, что правильная информация – это больше, чем половина дела с точки зрения знания. Ну, это полдела, скажем так. Изменение поведения – это совсем другой шарик воска.
Мэтью Уокер: Да, и сложнее, может быть, тоже.
Отслеживание вашего сна
Крис Крессер: Информации определенно недостаточно для изменения поведения. Но я думаю, что многие люди просто не знают, что вы только что сказали. Так что отчасти это вопрос неосведомленности о том, сколько на самом деле нужно сна для оптимального здоровья и работоспособности. И еще вопрос в том, как, черт возьми, я найду девять с половиной часов в постели, когда у меня будет семья, работа и все остальное, что связано с современным образом жизни.
Но так как мы говорим о отслеживание снатакие вещи, как коэффициент эффективности сна и сколько вы на самом деле спите, когда вы в постели. Многие люди этого не делают, это не будет для них очевидным, потому что они спят, или они ворочаются и, возможно, не спят. Итак, какие ваши предпочтительные методы отслеживания сна для потребителей, которые не могут находиться в лаборатории в данный момент?
Мэтью Уокер: Да, это сложно. Я думаю, что большинство устройств прямо сейчас, вроде наручных часов или колец, которые вы можете носить, отлично справляются с задачей определения общего времени сна. Проблема в том, что они не очень хороши в выделении всех различных уникальных стадий сна, которые я мог бы сделать в моем центре сна здесь, в Беркли. Поэтому я думаю, что сейчас они, вероятно, колеблются с точностью от 65 до 75 процентов. И я думаю, что мы поправимся …
Крис Крессер: По сравнению с полисомнографией?
Мэтью Уокер: Это верно. Так, Полисомнография по сути делает исследование сна, Вы похожи на спагетти-монстра со всеми этими проводами, идущими от вашей головы и вашего лица, но это позволяет нам измерить ваш сон с точностью золотого стандарта. Так что это относительно этого золотого стандарта. Мы туда доберемся? Я думаю, что мы будем. Что касается, так что, я думаю, одна проблема – это точность, которую нам еще предстоит решить.
Второй просто фактор формы, Я очень влюбился в концепцию, которую я бы назвал «неуязвимой», когда дело доходит до отслеживания сна. Потому что, когда мы ложимся спать, мы обычно снимаем вещи, мы не одеваем вещи. И поэтому я не думаю, что эти устройства с оголовьем, вероятно, будут очень липкими. Для большинства людей, я думаю, вы должны быть очень спящими и любопытными, чтобы поддерживать этот долгосрочный срок. Я думаю, что наручные часы, вероятно, чувствуют себя немного чуждыми для некоторых людей, и поэтому приверженность к сну обычно снижается. Я думаю, что кольцо является лучшим форм-фактором для этого, потому что люди ложатся спать с обручальными кольцами и другими кольцами, и поэтому я думаю, что это менее навязчивый компонент.
И, наконец, я думаю, что, вероятно, лучшая надежда, которая у нас есть сейчас, это матрас, Я думаю, что он может быть одним из лучших трекеров сна. И для меня удивительно, что мы не сделали больше в этом пространстве. Мы, если вы думаете об автомобиле, который у вас есть сейчас, относительно автомобиля 1950-х годов, ваш автомобиль теперь полон невероятных датчиков, которые всегда измеряют состояние и состояние этого автомобиля. Если вы думаете о своем матрасе в 1950 году относительно вашего матраса сейчас, они намного больше похожи, чем они отличаются.
Крис Крессер: Правильно.
Мэтью Уокер: Почему это? И вы думаете об автомобиле, если вам не повезло, вы можете потратить, я не знаю, от 5 до 10 процентов своей жизни в своей машине. Ну, вы должны потратить 30 процентов своей жизни на матрасе. Но все же мы этого не делаем. «На» вашем матрасе, а не «на». Если вы находитесь на матрасе, возникает другая проблема. Но я думаю, что это несоразмерное смещение технологий, а также смещение расходов на эти вещи. Поэтому я надеюсь, что это нарушит режим отслеживания. Я думаю, что мы доберемся с точностью, а затем расскажем о форм-факторе, который, на мой взгляд, также лучше.
Крис Крессер: Я имею в виду, что это замечательный момент, у нас есть, например, Bluetooth и Wi-Fi в кофеварках, чтобы громко плакать. Вы можете использовать свой телефон, чтобы начать делать эспрессо. Но матрас относительно не изменился, и это такой важный кусок нашей жизни.
Образцы сна ночных сов и жаворонков
Крис Крессер: Итак, мы немного поговорили об оптимальной продолжительности сна и о том, сколько сна нужно большинству людей. Имеет ли значение, когда происходит сон? Итак, вы слышите, как люди говорят, я сова. Итак, я ложусь спать в два часа и просыпаюсь, даже если они спят по восемь часов, допустим, они просыпаются в 10 часов. Это физиологически отличается от того, как ложиться спать в девять и просыпаться в пять?
Мэтью Уокер: Это отличный вопрос, и это действительно мало обсуждаемый вопрос, я думаю. Итак, как вы упомянули, некоторые люди – совы, другие – утренние жаворонки, а другие – где-то посередине. И это то, что мы называем ваши хронотип, Итак, вы утренний тип, вечерний тип? Около трети населения – это утренние, около трети – вечерние, а другая треть – где-то посередине. Почему это важно?
Ну, это важно, потому что, похоже, это влияет на количество и качество вашего сна. Итак, примером может служить то, что я часто обращаюсь ко мне как с пациентами, так и с людьми, которые говорят: «Слушай, я встаю в кровать, и у меня ужасная бессонница. Я не могу заснуть в течение первых полутора часов ». А потом я скажу:« Хорошо, в какое время вы ложитесь спать? »И они говорили:« Ну, я ложусь спать в 10 часов вечера ». because I have to wake up at 6 a.m. to get to work.” And then I’ll say, “Well, what if you were on a desert island and you had no commitments, nobody thought to wake up for nothing? When would you just like to go to bed? And when would you like to wake up?” And they would say, “Well, I’m actually more of an evening person, I’d like to probably go to bed around 1 a.m. and maybe sort of wake up at nine or 10 a.m. the following morning.”
What’s happening there is that they probably don’t have insomnia. They have a mismatch between the enforced sleep window, and their natural biological chronotype. In other words, they’re getting into bed when their biology and physiology is not yet ready to ramp up this thing called sleep. And it masquerades as sleep-onset insomnia, difficulty falling asleep.
So I think it’s important to sort of try to ask yourself, what type are you? And then ask, “Is there a chance that I could try and alter my schedule to fit better with that?” Now, that’s very difficult, I understand, for many people with lots of responsibilities, such as jobs and family. But even if you can’t, I hope that information at least helps you perhaps understand why some of your sleep may not be as ideal as it could be.
Chris Kresser: Right. And is, I’ve read that this is also an issue with teenagers, this chronotype change throughout life. And if a teenager naturally, the chronotype shifts where they are going to sleep later and waking up later. There’s been a movement in California, I think Gavin Newsom is supportive of it, to make school start times later for kids on the basis of some of this research.
Matthew Walker: Yes, and I think it is a critical movement to push forward. Firstly, we know that your chronotype is genetically defined. So at the point of birth, in fact, of course, before, you don’t get a choice as to whether you’re an evening type or a morning type, It’s gifted to you by your genetics. And as with most biology, when you fight biology or genetics, you typically lose. And the way you know you’ve lost is through disease and sickness. And so I think that’s the first thing to realize. It’s not under your control, really.
So don’t blame yourself or beat yourself up for being an evening type. Because society, really, I think, quite stigmatizes evening types as being lazy. The early bird catches the worm or this sort of nonsense. So yes, we’re all gifted with our chronotype. But our preference for sleeping phase does change across the lifespan. When we’re young kids, even though we’d love to stay up, even if we’re an evening type genetically defined, you still will struggle because you’ll still overall when you’re young be getting to sleep earlier and waking up earlier, much to the chagrin of young parents on the latter. But then as we transition through adolescence, there is a remarkable shift in your spots called your circadian rhythm, your 24-hour rhythm, to where you want to go to bed later and wake up later.
And again, it’s not the teenager’s fault that they, they, this, it’s just part of their preprogrammed biological development. And then as we get into adulthood, we kind of find our sort of overall adult sweet spot. But then oddly, as we go into older age, that circadian rhythm starts to get dragged backwards, and we start to want to go to bed earlier and then wake up earlier. And that’s the reason in Florida, you’ve got things like the early-bird specials, and that is because of this biological change. So, for adolescence though, it is critical. The data is very clear on this.
When kids start going to school later, kids of all ages, but especially teenagers, firstly, we see that academic grades increase. But we also see that behavioral problems decrease, truancy rates decrease, psychological and psychiatric referrals also decrease. But then something else was strange that happened in that story of later school start times around the country, which was that the life expectancy of those students increased. And you may be thinking, well, how can you, how do you measure that? How do you understand that? The leading cause of death in late-stage teenagers in most developed nations is actually not suicide. That’s second. It’s road traffic accidents.
Chris Kresser: Right.
Matthew Walker: And here, sleep matters enormously. And I’ll just give you one example that happened in Teton County in Wyoming. They shifted their school start times from a rather ridiculous 7:35 in the morning, to 8:55 in the morning. Now, in addition to those kids reporting getting an extra hour of sleep that following year, what they ended up seeing was a 70 percent drop in car crashes in those teenagers that following year.
To put that in context, the advent of ABS technology in cars, which is antilock brake systems, that dropped accident rates by 20 to 25 percent, and it was deemed a revolution. But here is a biological factor, giving our next generation sufficient sleep, that will drop accident rates by 70 percent. So I think, I really hope Gavin passes the bill here in California, just like has happened in other states. Because if our goal as educators truly is to educate and not risk lives in the process, then we are failing our children in the most spectacular manner with this incessant model of early school start times.
Chris Kresser: Absolutely. And as parents and protectors of the health of future generations, this is a serious moral and ethical issue.
Matthew Walker: It really is.
Chris Kresser: Yeah.
Matthew Walker: It really is. When sleep is abundant, minds flourish. And when it’s not, they don’t.
How Naps, Meditation, and Medication Affect Sleep
Chris Kresser: Yeah, it’s as simple as that. Okay, so we’ve talked a little about chronotypes, different durations, timings of sleep. The next question is napping and catching up on lost sleep, if, for example, you’re someone that can’t for whatever reason, get the appropriate amount of sleep during the night. How do you make that up? And I mean, does that work, for example? Does napping replace sleep debt through the night? Maybe let’s start there. And I have a few other follow-up questions.
Matthew Walker: Yeah, so, it’s a little bit complicated. But let’s pick it apart. Firstly, what we know is that sleep is not like the bank, retrospectively. You can’t accumulate a debt and then hope to pay it off at some later point in time. So, for example, if you under-sleep one night, your immune system is going to be compromised the next day. And for that day, whilst you are compromised, you’re going to be suffering higher risk of infection, as well as things like cancer.
But when you get some recovery sleep that following night, it doesn’t remove or go back in time and sort of wipe away that vulnerability. You’ve suffered that vulnerability, there’s nothing you can do. But it doesn’t mean that you can’t de-risk the future by then sleeping enough and getting that sleep. So, but, in terms of naps, the reason why it’s a little bit tricky is, as I mentioned, for hunter–gatherer tribes, they make up on a 24-hour basis their sleep in a different way than we do. They sort of sleep a good solid bout at night and then they have a nap/siesta-like behavior in the mid to late afternoon.
So they get their fill of sleep, but they do it consistently. They’re not short sleeping during the week and then bingeing at the weekend, which is what typically we see, which is almost what I would describe as sort of the “sleep bulimia,” this sort of binge–purge sort of approach to sleep. And that’s not good. It creates what we call social jet lag, which is where on Friday and Saturday, maybe you’re going to bed at midnight or one and you’re waking up at 9, 10, 11.
But then come Sunday night, you’ve got to drag your biological clock all the way back to going to bed at 10, and you’re doing that every weekend, that’s essentially like flying back and forth from New York to San Francisco every week.
Chris Kresser: Right, it’s self-imposed shift work.
Matthew Walker: And that’s torture on your body. Yeah, it is, it is a form of social shift work, social jet lag. And we can see, there’s been some great studies showing the health consequences of that behavior. So that’s really the first piece of advice I can give you for better sleep is regularity. Go to bed at the same time, wake up at the same time, no matter whether it’s the weekday or the weekend. Regularity is king. It’s what our bodies were designed to receive. And it will help anchor your sleep and improve both the quantity and the quality of that sleep.
Chris Kresser: So it sounds like napping, assuming you’re asleep, does count towards the total amount of sleep you need in a 24-hour period. What about meditation?
Matthew Walker: Well, I should note, by the way, for naps. Naps can be a double-edged sword. When we’re awake during the day, we build up a healthy sleepiness, and it’s due to a chemical called adenosine. And the more of that adenosine that builds up, in other words, the longer that you’re awake, the sleepier you will feel. And after about 16 hours of being awake, you should feel plenty sleepy. You should have enough of this sleepiness pressure or adenosine chemical to weigh you down so that you fall asleep easily and then stay asleep. And it’s during sleep that the brain actually takes away that adenosine chemical. It removes it and therefore we wake up after about eight hours feeling refreshed, or we should do.
So why does this make any difference to naps? Well, if you’re taking a nap in the late afternoon, it’s almost like a pressure valve cooker. And a nap will just release some of that healthy sleepiness. And therefore, you may struggle to fall asleep at your normal time at night, and/or stay asleep. So the advice is, if you can nap regularly, or you don’t have problems with sleep at night, then naps can be okay. But if you can’t nap regularly, and especially if you struggle with sleep at night, you should not nap. You should stay awake, build up all of that healthy sleepiness to help you sleep better at night and stay asleep, if that makes sense.
Chris Kresser: It does, yeah. And I think that’s an important point, especially for people who don’t sleep well. Because they are the very ones who might think that napping could benefit them.
Matthew Walker: Right. Yeah, you can fall in, and it’s a very easy trap to fall into. But you should really resist that. It’s something that we strongly advocate.
Meditation, great question. Meditation seems to give some similar benefits to sleep for both brain and the body. But what’s interesting is that if you put people into a brain scanner, or you measure their actual brainwave activity, as we’ve done, meditation does not produce a brain state that is similar to sleep.
So I think my understanding right now for meditation versus sleep, if you want to sort of put them on a Coke/Pepsi head-to-head challenge, yes, they both give benefits. Perhaps similar benefits. But the physiological route through which they accomplish and achieve those benefits seems to be different. And as a consequence, meditation is not a substitute for sleep. Is meditation, however, beneficial to help you sleep? It actually is. So for people who are struggling with sleep at night, meditation has actually been proven to be very efficacious, The studies are really quite powerful.
So it’s one of the tools that people are increasingly using clinically to try and help people sleep. And if you look at some of these popular meditation apps, like Calm или Headspace, and you sort of try to inquire about the usage statistics, they would obviously start it off by thinking we would like people to meditate in the morning or during the day. Where they saw a lot of uptick in the use of these apps was right around bedtime, and people were self-medicating their sleep troubles with meditation.
Chris Kresser: Yeah, self-meditation.
Matthew Walker: Yeah, self-meditation/self-medication. So I think meditation, that’s really the relationship in terms of sleep that’s become interesting.
Chris Kresser: Interesting.
Matthew Walker: Less so, if you meditate, can you get less sleep? The answer seems to be no, because they’re two physiologically different processes.
Chris Kresser: Right, that’s helpful. So meditation is a lever, one of the things you can do to improve your sleep, but not something that can replace sleep.
Matthew Walker: That’s right.
What You Can Do to Improve Your Sleep
Chris Kresser: So, I think a lot of people are aware of the importance of sleep, at least in my audience. They’re aware of the importance of sleep, they, whether or not they’re struggling with finding enough time to be in bed, I think many people are. But then there’s the issue of insomnia, People who are actually spending the required amount of time in bed, but they are suffering from insomnia for any number of reasons. And we don’t have time, obviously, to go into all of the causes of insomnia, and they can vary a lot from person to person.
But in terms of just general sleep hygiene and general tips for developing better sleep habits, what are the things that you have seen from the research and also your work and the Center for Human Sleep Science that make the biggest impact for the greatest number of people?
Matthew Walker: Yeah, so, I think for insomnia, just to put a sticky on it, there are essentially two flavors that we think about for insomnia, which is sleep-onset insomnia versus sleep-maintenance insomnia, In other words, I have difficulty falling asleep versus I have difficulty staying asleep. Right now, the treatment recommendation is not first-line treatment with sleeping pills. Unfortunately, the evidence is growing. Those sleeping pills seem to increase your risk of mortality significantly. They’ve also been associated with a high risk of cancer development.
Do we know that those studies are causal? No, we don’t. They could be associational. Although there is some animal work to suggest it could be causal. Will we ever find out if it’s causal? Based on the strength of the relationship between mortality and the carcinogenic nature of those, I think it’s probably unlikely that we would ever get ethical approval to do studies. That’s how strong that evidence is.
Chris Kresser: Right.
Matthew Walker: So sleeping pills in 2016, the American College of Physicians said on the basis of that, plus the nominal benefit that you get relative to placebo, the first-line treatment must not be sleeping pills. It must be something called cognitive behavioral therapy for insomnia, or CBTI, And there you work with a clinically trained therapist. The benefits on sleep are just as big, if not bigger, than what typically you see in terms of sleeping pills.
But more beneficial is that once you start working with that therapist, you maintain that benefit, some studies have shown up to a year, even five years, most recently. But yet, if you stop taking sleeping pills, not only do you go back to the bad sleep that you were having, you actually have what’s called rebound insomnia, where your sleep is even worse. So I don’t think sleeping pills are really the answer, at least not the ones that we have right now.
Chris Kresser: And this is true across all of the classes of sleep medications.
Matthew Walker: Unfortunately.
Chris Kresser: … Lunesta, Ambien, Sonata, etc.
Matthew Walker: Yeah, they all do essentially the same thing. They’re all trying to essentially tickle a type of receptor in the brain that’s called the GABA receptor. And that’s the principal inhibitory receptor of the brain. What those drugs essentially do is knock out your cortex. And so they’re a class of drugs that we call the sedative hypnotic. And sedation is not sleep. But when you take these drugs, you mistake the former for the latter. Now, I’m not saying that when you take those sleeping pills that you’re awake. You’re clearly not. But to argue that you’re in naturalistic sleep is an equal falsehood.
Chris Kresser: Right.
Matthew Walker: And if I were to show you your electrical signature of sleep, when you’re on versus off those drugs, it looks very different.
Chris Kresser: Do they increase light sleep and decrease deep sleep, these drugs?
Matthew Walker: They can, it depends on how you quantify that sleep. If you just score the sleep itself, it looks more like a sedated sort of deep sleep. But if you look at the electrical profile, which is really the best metric that we have of the quality of sleep, it doesn’t look like good-quality sleep. So, and I think also people have issues with tolerance, they typically can experience a sort of a hangover effect in the morning as well, even with some of the more shorter-acting compounds.
I think the bottom line is that sleep, if you understand the biology, is an incredibly complex, physiological ballet of different things. And to think that we could orchestrate that sort of ballet with just a simple basic drug is probably unlikely. That’s what we’re finding. Our sleep solutions pharmacologically are going to have to be pluripotent. We’re going to have to have multiple different skews by which they try to sort of improve sleep. They have to pull all of the different levers at all of the right times in all of the right brain areas to really mimic naturalistic sleep. So I think we’re a little bit off that in terms of solutions, but we’ve got a great behavioral alternative, which people can turn to.
Chris Kresser: Right. And yet 50 to 70 million Americans are taking these medications. And they unfortunately, all too often are prescribed as a first-line therapy. And to me, and what strikes me about this, like we talk on this show and in general a lot about the ancestral or evolutionary perspective, And it seems to me that several aspects of the modern lifestyle are just antithetical to good sleep.
From circadian disruption with too much exposure to artificial blue light at night that impacts melatonin production, and not enough exposure to sunlight during the day, to the kind of always-on lifestyle that many of us live where we’re checking email, social media all times during the day. I know you’re well aware of all these statistics of what percentage of teens, especially, but even young adults, and adults in general, check their phone throughout the night and sleep with it in their bedroom. To the higher incidence now of chronic inflammatory diseases, because I know from my work with patients, that inflammatory disorders are very likely to interfere with sleep on like just a physiological basis, even if someone’s mind isn’t busy.
So what’s your impression of that and the challenges that the modern lifestyle presents in terms of sleep? How much of this is just evolutionary mismatch?
Five Things You Can Do to Improve Your Sleep
Matthew Walker: Yeah, my impression, I actually don’t do impressions. My training is strictly in science. But I think to come back, you sort of asked me, what would be my tips for those who don’t have clinical insomnia to try? And I think it speaks to this issue to what would be, let’s say, the five things that people could start doing tonight to get better sleep.
1. Set a Regular Sleep Schedule
The first, we’ve already spoken about, which is regularity. That really is, if there’s only one thing that you remember from this sort of podcast for sleep, it would be regularity, and especially the wake-up time. Really try to anchor that, and the rest of the regularity will almost take care of itself.
2. Control Your Temperature
The second component of that is temperature. So we know that with sort of this modernity shift, indoor living, we’ve also generated constant temperatures in our homes with air conditioning and central heating. That has been a remarkably difficult thing for our sleep system because your body needs to drop its core temperature by about two, two and a half degrees Fahrenheit, or about one degree Celsius, to fall asleep and then stay asleep. And it’s the reason you will always find it easier to fall asleep in a room that’s too cold than too hot. Because the cold is taking you in the right direction.
So a temperature around about 67-ish Fahrenheit is about optimal for most people. Now, you can play around with it, but it’s a lot colder than most people think. You can, if you get cold hands and feet, actually prevent yourself from falling asleep, because the way it works is that your hands and your feet radiate heat from your body. And you actually need to expel the temperature from the core of your body. How do you do that? Well, your hands and your feet are wonderful peripheral radiators of heat.
And this is the reason why when you get into a hot bath or a shower, you think that you sleep better. It’s actually not because you’re coming out nice and toasty. It’s because in the bath, you get massive vasodilation. All of the blood comes to the surface, you get rosy cheeks. That when you get out of the bath means that you have this enormous thermal dissipation of heat from the core of your body, which drops your core body temperature, and that’s why you fall asleep easier. So you can have a hot water bottle at the end of your bed, you can go to sort of sleep with some socks on to begin with to warm the feet to then cool the core of the body.
It’s paradoxical, but that’s how it works. But then, and then you need a nice, cool ambient temperature. Because you not only need to sort of essentially cool down to fall asleep, you need to stay cool to stay asleep. And that’s where the ambient core temperature is going to help you.
So the second, sorry—
Chris Kresser: That’s temperature. The second?
Matthew Walker: The second is temperature.
Chris Kresser: That has made the biggest impact on my sleep. I have been using the chiliPAD, or the OOLER, which you may be familiar with, the cooling sleep surface.
Matthew Walker: Yeah.
Chris Kresser: And we have one of the few houses I think in Berkeley I think with air conditioning, which has been, for me, when I go to the tropics or something, my sleep is just destroyed from being in that hot environment. So temperature is number two, regularity is number one.
Matthew Walker: Temperature, number two, yeah.
Chris Kresser: And how about number three?
3. Keep It Dark
Matthew Walker: Number three is darkness. We are a dark-deprived society in this modern era. So trying to shut down those screens in the last hour before bed. We know that that has a deleterious impact. There was a study that was done where you did one hour of iPad reading before bed versus just reading a normal paper book in dim light. And that one hour of iPad reading, firstly, it reduced the amount of this sleep sort of timing chemical called melatonin. It dropped that melatonin level by 50 percent.
Chris Kresser: Wow.
Matthew Walker: Furthermore, it delayed the peak of that melatonin release by three hours. So if we did an hour of iPad reading here in Berkeley before bed, we would be much closer to Hawaii time than we would be California time.
Chris Kresser: Right.
Matthew Walker: And what was also interesting is that when they stopped, it also blocked their rapid eye movement sleep, by the way, their dream sleep, which we know is essential for a number of functions. But the more fascinating thing was, when they stopped the iPad reading, they didn’t immediately return to good sleep. It actually had a blast radius, where the sleep didn’t recover until two or three nights later. So I think darkness is a critical component.
Again, it’s a way that we’ve been dislocated from our natural sort of physiological interaction with the environment when it comes to sleep through the Industrial Revolution and now the digital one. It’s not just devices though, it’s also just overhead lighting. So in the last hour before bed, try to dim down half of the lights in your house. You don’t need them all on, and you’d be surprised at how soporific that actually is. So that’s number three.
4. Don’t Remain in Bed Awake
Number four is walk it out. And what I mean by this is don’t remain in bed awake for too long. And the cutoff is usually about 20 to 25 minutes. If you’ve been trying to fall asleep or you’ve woken up and you’re trying to fall back asleep, and you’re not asleep after about 20 or 25 minutes, get out of bed and go to a different room and in dim light, just kind of read a book or a magazine. And don’t check email, don’t do any of that. And the reason is the following. Your brain is an incredibly associative device. And very quickly it learns that your bed is the place of being awake, not asleep.
And so I hear this from people. They’re saying, “Look, I’m I’m watching television on the couch and I’m falling asleep and then I get into bed and I’m wide awake. And I don’t know why.” And it’s because the brain has learned that association. So you need to break that association and you only return to bed when you are sleepy and there’s no time limit. And that way you will relearn the association that you once, of course, had as a child which is your bedroom is the place of sleep not wake.
Chris Kresser: So even when people have to get over their anxiety, I’m not sleeping enough and Dr. Walker told me I have to sleep.
Matthew Walker: That’s right. It’s very natural.
Chris Kresser: Or so they have to …
Matthew Walker: You’re setting yourself up, yeah.
Chris Kresser: … they’ve got to give themselves permission to just reset that for whatever period of time that takes, knowing that it will help them in the long run.
Matthew Walker: That’s right. Correct. We’re trying to sort of think about the long-term plan here. We have to accept the short-term loss for a long-term gain. So the analogy that I guess there would be, you’d never sit at the dinner table waiting to get hungry. So why would you lay in bed waiting to get sleepy? And the answer is you shouldn’t. You should get out of bed.
5. Limit Caffeine and Alcohol
The final and fifth one usually makes me very unpopular. I mean, I’m generally very unpopular in truth, but this one especially. Which is alcohol and caffeine. Everyone knows, of course, that caffeine can help you wake up, it’s a stimulant. It’s a psychoactive stimulant and actually the only psychoactive stimulant that I know of that we readily give to our children without too much thought. But caffeine is a problem for sleep for a number of ways.
Firstly, of course, it will keep you awake. It’s more difficult to fall asleep and/or stay asleep if you have caffeine in your system. But also, the other interesting part of caffeine is that its half life and its quarter life are probably not well-known by the public. Caffeine has a half life of about six hours. In other words, after about six hours, half of that caffeine is still swirling around in your brain, but it has a quarter life of 12 hours.
So in other words, if you have a coffee at noon, a quarter of that caffeine is still in your brain at midnight. So having a coffee at noon is the equivalent of sort of tucking yourself into bed at midnight and before you turn the light off, you swig a quarter of a cup of Starbucks and you hope for a good night of sleep. And it’s probably not going to happen.
Chris Kresser: And that’s if you just had one cup.
Matthew Walker: That’s right. And so that’s one of the issues that the recommendations usually try to cut off about sort of 14 hours before your expected bedtime. The other issue though, some people will say like, “I’m one of those folks who can have an espresso with dinner, and I fall asleep fine, and I just stay asleep.” Even if that’s true, we’ve done these studies where we give you a standard dose of caffeine, that’s 880 milligrams in the evening. Even if you fall asleep and stay asleep, the depth of your deep sleep is nowhere near as deep. In fact, it’s usually about 20 percent less. There’s a 20 percent impairment or reduction in your deep sleep. And to put that in context, I would probably have to age you by about 30 years to get that type of a drop in deep sleep. Or you could do it every night with a cup of coffee with dinner. So that’s caffeine.
Chris Kresser: Yes.
Matthew Walker: Alcohol. Alcohol is probably the most misunderstood “sleep aid.” It isn’t a sleep aid at all. Alcohol, again, is a class of drugs in the sedative category. So when you have a nightcap, you’re just knocking the cortex out again. You’re not going into naturalistic sleep. You think you fall asleep faster, but you’re just sedating the brain. Then there’s two other problems with alcohol.
Firstly, it will fragment your sleep. So you wake up many more times throughout the night. And you wake up feeling unrefreshed, but you typically don’t remember those awakenings. So you don’t put two and two together. And the final component of alcohol is that it’s actually very good at blocking your rapid eye movement sleep, your dream sleep. And so again, alcohol is really one of those things to be avoided if you can in the evening.
I typically would offer the non-politically correct good advice as a Britishman, which would be if you are going to drink, just go to the pub in the morning, and that way the alcohol is out of your system by the evening. But I would never say that on a health podcast in public.
Chris Kresser: Yeah, well, you’re not here to be popular, you’re here to educate us on the importance of sleep and how to get better-quality and more sleep. And I appreciate that. Because as a healthcare practitioner myself, I see so many people that I think are suffering health problems that are at least partially related to sleep deficit. And it’s so easy to look in other places, rather than just looking at the simple, some of the simple things, like diet and sleep, for example.
Matthew Walker: It’s so true. I think we’re always trying to optimize for these different sorts of physiological systems, how do I optimize my cardiovascular health or my glucose regulation or my cognition. When we fail to realize that sleep, in fact, is the tide that raises all health boats, it’s the superordinate node. And you can almost think of sleep from a health kind of augmenting perspective.
It’s a little bit like one of those big music-mixing decks that you see in these studios, where they’ve got all of the different dials, which are all of the different biological systems. And then there’s that one dial all the way over on the left, which if you move it up, all of the other dials go with it. That is sleep. It’s the Archimedes’ lever. And if you focus on that, you will be doing a remarkable service to your both healthspan and lifespan.
Chris Kresser: Fantastic point. I love that analogy. So your most recent book, Why We Sleep, was a real tour de force. It was one of my favorite science books I’ve ever read.
Matthew Walker: Oh, thank you.
Chris Kresser: So comprehensive and such a great job of pulling together all of the relevant literature and yet explaining it in an accessible way that the lay person can understand. And I think, I highly recommend reading it. Even if it is a little bit alarming for many people, I think sometimes wake up calls are necessary. And this is one that not only for our own health, but particularly for our children’s health and future generations, as you pointed out earlier that we’re, there’s a real moral and ethical issue here to consider, and we can all become our own advocates for sleep and advocates for our children and future generations.
So, Dr. Walker, thank you so much for your pioneering work, your book, Why We Sleep, which is available everywhere that books are sold. I highly recommend that, and I could have easily kept talking to you for a couple hours. I know you have to go. So maybe we’ll have you back on the show in the future at some point.
Matthew Walker: I would love that, Chris. And Dr. Kresser is what I should call you, but thank you so much for having me here. It’s a message that I’m desperately trying to get out there. I would love to try and help reunite humanity with the sleep that it is so clearly bereft of. So I have to anoint you as a sleep ambassador now for giving me this platform. So, thank you for that.
Chris Kresser: And you’re welcome. I’ll come down to your center and visit sometime soon, since we’re not so far away.
Matthew Walker: I would love that. And thank you again for this opportunity.
Chris Kresser: Take care, thanks again.
Matthew Walker: Okay, you take care.
Chris Kresser: Bye.
Matthew Walker: Bye.