The World’s No.1 Sleep Expert: The 6 Sleep Hacks You NEED! Matthew Walker

1. 0:00 – 2:25

   Intro

   1. MWMatthew Walker0:00

      When you're struggling with sleep in the middle of the night and you're wide awake, in the last hour before bed, try this experiment.

   2. SBSteven Bartlett0:08

      I'm s- I'm sold. Matthew Walker.

   3. MWMatthew Walker0:11

      Neuroscientist and best-selling author.

   4. SBSteven Bartlett0:13

      And one of the world's leading researchers in sleep science. It's gonna blow your mind.

   5. MWMatthew Walker0:19

      There is a global sleep loss epidemic shaped by this thing called the modern world. What society wants is that you're either producing or you're consuming. In fact, the CEO of Netflix, his statement was that we are to commit war against sleep. We have this mentality in business, less sleep equals more productivity. That is just not true. Insufficient sleep costs most nations about $411 billion.

   6. SBSteven Bartlett0:44

      Jesus.

   7. MWMatthew Walker0:45

      Your rates of obesity, cardiovascular disease, mental health conditions, all of these things escalate. If that wasn't bad enough-

   8. SBSteven Bartlett0:51

      Oh, God.

   9. MWMatthew Walker0:52

      ... if you're not getting sufficient sleep, then 60% of all of the weight that you lose will come from lean muscle mass and not fat.

   10. SBSteven Bartlett1:03

       Not the muscle. How would you redesign society to help us to sleep better?

   11. MWMatthew Walker1:08

       So first, I would-

   12. SBSteven Bartlett1:09

       It feels like caffeine is a miracle drug with no apparent cost. Was I wrong or was I right?

   13. MWMatthew Walker1:16

       Wrong. Caffeine will hurt your sleep in three ways most people are not aware of. So if you have a cup of coffee at midday, what happens is that-

   14. SBSteven Bartlett1:28

       Before we get into this episode, just wanted to say thank you, first and foremost, for being part of this community. Um, the team here at The Diary of a CEO is now almost 30 people, and that's literally because you watch and you subscribe and you, um, leave comments and you like the videos that th- this show's been able to grow. And it's the greatest honor of my life to sit here with these incredible people and just selfishly ask some questions that I'm pondering over or worrying about in my life. But this is just the beginning for The Diary of a CEO. We've got big, big plans to scale this show, um, to every corner of the world and to, to, to diversify our guest selection, and that's enabled by you, by a simple thing that you guys do, which is to watch. So, if there's one thing you could do to help this show and to help us continue to do what we do, it's just to hit the subscribe button. If you like this show, if you like what we do here, if you watch these episodes, please just hit that subscribe button. It means the world. Let's get on with it.

2. 2:25 – 5:15

   Why is your work so important?

   1. SBSteven Bartlett2:25

      Matt, I have spent the longest time trying to sit down with you on this podcast, so I'm very, very happy to- Mm-hmm. ... spend some time with you today. And that is because your, your work is now world-renowned, um, and it's very, very important work. But, as is the case with a few of the recent episodes on this podcast, I wanted to start by asking you, in your view, what is it you do and why is it so important, in your mind, that you do it?

   2. MWMatthew Walker2:56

      Well, firstly, thank you so much for having me here and having this conversation. It's, uh, an incredible privilege to sit with you. Um, why do I do what I do and why do I think it's important? Um, sleep, I would argue, is the single most effective thing that you can do to reset your brain and body health. And I don't say that flippantly. It's not as though I'm dismissing exercise or diet. Those two things are absolutely critical. But if I were to take you, the individual, and deprive you of exercise for a day, deprive you of food for a day, deprive you of water for a day, or deprive you of sleep for a day, 24 hours, and I were to map your brain and body impairments, it's not even a competition. That one night of lost sleep relative to those other things, it dwarfs... You know, the only thing I lose out against is oxygen. If I deprive you oxygen, you're going to pop out (laughs) of existence a little bit quicker than you will with a lack of sleep. So, sleep to me, I think, is the elixir of life. It is your life support system, and as best we can tell, I would argue it's Mother Nature's best effort yet at immortality. And so in that regard, that's why I, when I look across all of the studies and all of the data, it's so compelling to me. And part of the reason I think it's... I've desperately tried, and I haven't done a good job, but I've tried to offer some public mission of reuniting humanity with the sleep that it's so bereft of, is because it does appear that there is a global sleep loss epidemic if you look at the numbers. People are struggling so desperately with their sleep. So we have all of this knowledge, this incredible knowledge of sleep and how important it is, and it's a perfect storm colliding with this great sleep depression in modern society. And for that reason, I just felt as though, what can I do to try to help offer this voice and this science? And I am but a scientist, and I stand on the shoulders of all of my colleagues and all of these giants in the field. I'm just a researcher. So, that's a little bit about, I guess, who I am, but more about why I do it and

3. 5:15 – 10:07

   Work and research life

   1. MWMatthew Walker5:15

      why I think it's important.

   2. SBSteven Bartlett5:16

      If I were to try and define your sort of... And this, I hate doing this because it requires the application of some kind of narrow label. If I was to try and define what your title is, in your own words, what would that be?

   3. MWMatthew Walker5:27

      So, I'm just a professor of neuroscience, of brain science, at the University of California, Berkeley. Um, I am, I am not a medical doctor, just FYI, for all of the things that we will talk about in this conversation. Uh, so I'm just a PhD.

   4. SBSteven Bartlett5:42

      Just a PhD?

   5. MWMatthew Walker5:43

      Yeah. (laughs)

   6. SBSteven Bartlett5:44

      You know, that's, um, incredibly humble of you, but, but I would assert that you're, without a shadow of a doubt, the leading author, scientist, commentator, voice, as it relates to the topic of sleep. And my, my, my question from that is...Where did that begin? Like, where did that start in your life, in the journey of your life?

   7. MWMatthew Walker6:06

      Mm-hmm.

   8. SBSteven Bartlett6:07

      When did sleep become the thing?

   9. MWMatthew Walker6:11

      (laughs) It occurred to me, or happened to me I should say, when I was doing my PhD. I was studying people with dementia, and we were trying to understand what type of different dementia that they had very early on in the course of their disease, and we were looking at patterns of brainwave activity, so I was placing electrodes all over their head and I was measuring them, and I was trying to differentially diagnose them very early on, and I was getting no good data whatsoever. It was miserable. Nothing was, was landing. And one day, I went home, uh, at the weekend and sort of w- with all of my printed journals, and I go to the, my doctor's residence and have this sort of igloo of journals around me that I would sit and read at the weekend, um, and I was, which probably tells you everything about my social life over the weekend if that's what I was doing, but... Um, so I was reading these journals, and it occurred to me that some of these dementias were eating away at the sleep centers in the brain and others would leave them untouched, and at that moment, I realized, "I'm measuring my patients at the wrong time. I'm measuring them when they're awake. Should be measuring them when they're asleep." Started doing that, got amazing results, and at that point, I wanted to ask the question, "Well, I wonder if the sleep problems are not simply a symptom of the dementia. I wonder if it's a potential cause of the dementia." And at that point, I started to think, "Well, so then what is this thing called sleep?" And what I learned is that some of the greatest minds in the past 100 years had tried to answer a very simple question: Why do we sleep? And, you know, 30 years ago, in fact, the crass answer was that we sleep to cure sleepiness, (laughs) which tells you nothing about ...

   10. SBSteven Bartlett8:03

       (laughs)

   11. MWMatthew Walker8:03

       You know, it's like saying, "I eat to cure hunger." Well, no, you ... That's not the right answer. N- now, 30 years later, we've had to upend the question, and we now have to ask, "Is there any physiological system in your body, is there any operation of your mind that isn't wonderfully enhanced when you get sleep or demonstrably impaired when you don't get enough?" And the answer seems to be, to be no, there. So, my journey into the science of sleep really was an accident, but at that moment in time, when I started reading about sleep, I utterly fell in love with the topic, and it is a love affair that has lasted me over 20 years. I think it is the most beguiling topic in all of science. I'm biased, of course. Um, and I will never study anything different. I know that now. I'll study it till the end of my career and until the end of my life.

   12. SBSteven Bartlett9:00

       Wow. I've never had anybody say to me on this podcast that they would study the same topic for the rest of their life, and you're a young man. That's a ... You got a long way to go-

   13. MWMatthew Walker9:10

       (laughs) Uh-

   14. SBSteven Bartlett9:11

       ... especially with the amount you've been sleeping.

   15. MWMatthew Walker9:12

       That's very kind of you to say.

   16. SBSteven Bartlett9:13

       You're three times 150.

   17. MWMatthew Walker9:14

       I w- I w- I wish... I'm, I'm moving into the foothills of middle age, uh, rapidly, but... No. I, I'm so fortunate in what I do, um, to have found it or for it to have found me. You know? If I won all of the money in the world tomorrow, I would genuinely, genuinely not do anything different. Um, I, I am so fortunate. Well, I'd probably start trying to fly, like, business class or first class. That would be nice. But other than that, um, I would do nothing different, and I am very mindful of that because that sounds very privileged, and I know a lot of people endure what they do for a living rather than enjoy what they do for a living, and I know how lucky I am. So, I don't mean to be dismissive of, of people in that regard. I just know how much I love what I do.

4. 10:07 – 18:14

   Why do we sleep?

   1. MWMatthew Walker10:07

   2. SBSteven Bartlett10:07

      You, you asked a question there which is, um, you, you, you posed a question which many people have tried to answer. You gave the, the answer from 30 years ago about, you know, why do we sleep? Um, and it dawned on me as you said that, that I've never asked myself that question.

   3. MWMatthew Walker10:22

      (laughs)

   4. SBSteven Bartlett10:22

      I've never even pondered the thought of why I sleep. I mean, I know what happens when I sleep, but do I know why my body can't just find another way?

   5. MWMatthew Walker10:31

      (laughs)

   6. SBSteven Bartlett10:31

      Why can't my b- body stay awake for the 24 hours? I know some animals, they sleep half their brain and then the other half kind of-

   7. MWMatthew Walker10:36

      Mm-hmm.

   8. SBSteven Bartlett10:36

      ... has a nap and whatever. Why, why, why do we sleep?

   9. MWMatthew Walker10:40

      It's a puzzling question because when you think about it from an evolutionary perspective, it makes no sense whatsoever. Sleep is utterly idiotic because when you're sleeping, firstly, you're not finding a mate, you're not reproducing, you're not foraging for food, you're not caring for your young, and worst of all, you're vulnerable to predation. (laughs) Now, on any one of those grounds, but especially all of them as a collective, sleep should have been strongly selected against during the course of evolution, but from best we can tell, sleep evolved with life itself on this planet, and it has fought its way through heroically every step along the evolutionary path, and what that has told us is that sleep must be essential at the most basic of biological levels.

   10. SBSteven Bartlett11:36

       Mm-hmm.

   11. MWMatthew Walker11:36

       And now we understand that Mother Nature didn't make a spectacular blunder with this thing called sleep. Sleep, for example, will restock the weaponry in your immune arsenal, and it will make you a more immune-sensitive individual, so you're more immune robust when you wake up. We also know that it regulates your blood sugar levels. It controls your appetite hormones. It also regulates your sex hormones, testosterone, estrogen. Um, sleep upstairs within the brain will fixate memories and help you learn and remember. Sleep will deescalate anxiety. It will reduce your emotional difficulties and traumas. Sleep will actually cleanse away the Alzheimer's toxic proteins that build up in the brain. You know, e- the, the list is endless. These are all of the reasons that we need to sleep.

   12. SBSteven Bartlett12:31

       ... but why can't I just do what those animals do, where they... half of their brain falls asleep-

   13. MWMatthew Walker12:36

       (laughs)

   14. SBSteven Bartlett12:36

       ... and the other half of the brain stays awake? Is that at all linked to the fact that we, we live in tribes, so we are essentially... Although, we're, you know... there might be 10 people in a tribe. We're all 10% of the tribe, so we can rest at different times and kind of cover each other's backs, or...

   15. MWMatthew Walker12:51

       Gosh, yeah. So, actually there are two nested very insightful questions there. The first is this notion of what you're describing, which is wh- what we call uni-hemispheric sleep, which is just a fancy way of saying you can sleep with one half of your brain and the other half is wide awake. Now, there are only a few species that can do this. Um, for example, aquatic mammals. Dolphins are a great example. We can place, actually, electrodes on their heads, and you can see that one half of their brain will be fast asleep. It will be in deep, deep non-REM sleep. The other half of the brain will be frenetic, wide awake. And in part for them, the reason is because they need to maintain aquatic mobility. You know, they need to keep surfacing for air. Otherwise, you know, that's not going to be a good outcome. We also know that, uh, birds or ave- many avian species will have uni-hemispheric sleep. And you can actually see this. There's some great YouTube videos online where they will film one half of the... sort of the side of the, the bird's face, and the eye is closed. And what it means is that the other half of the brain, 'cause the brain is actually... the left half controls the right side, the right side controls the left side. So, that left side is now fast asleep, which is the right eye closed, and then you kind of pan around, and all of a sudden, the other eye is wide awake and it's clearly looking about. Now, this is obviously not for aquatic surfacing to gain air. This is for a different reason. What happens is that in a flock, a bunch of birds will l- all land on a branch. Now, all of the folks in the middle, they get to sleep with both halves of their brain. They can sleep with both halves or just one half. All of the folks in the middle, they get to sleep with both halves. The unfortunate girl or guy who sort of lands at the end, the far end, they will actually sleep with one half of their brain. So, one half of the flock, the entire flock, has one eye 180 degrees of sort of half panoramic view, uh, out. The other bird on the other end will have the other half of the brain asleep with the other eye awake, giving the other 180-degree view of protection, uh, vision. And therefore, the entire tribe has a 360-degree assessment. Now, you would think in fairness that once those guys or girls at the end have done their duty, they get to move into the middle, and they get to sleep with both halves. No, that's not what happens. What they will do after a while is that they will stand up, they will turn around 180 gr- degrees, sit back down, and switch the other h- sides of the brain.

   16. SBSteven Bartlett15:37

       Wow.

   17. MWMatthew Walker15:38

       So, to, to just be clear, the complexity of wiring and architecture that has to happen for one half of the brain to be deep in sleep and the other half to be wide awake is astronomically hard. I mean, it's incredibly difficult to create that wiring. What that tells me is that if sleep was dispensable, if it was negotiable, then Mother Nature would have just found a different way for us to get all of these brain and body benefits, and not gone to all of the evolutionary trouble of figuring out this fancy wiring for half brain sleep. In other words, you just can't get away from sleep. You have to sleep. But your second question, I think, is, is even more fascinating, which is us as a tribe, because we are a tribe species... Now, there is something else that we call your chronotype. Are you a morning type, evening type, or somewhere in between? And by the way, you don't get to decide. It's not your choice. You know, this notion of these go-getter type As who say everyone has to be awake at 5:00 in the morning. You know, you go to the gym, you blast out a workout for an hour, and you're at the desk by 6:00 AM. Um, you have no choice. If you're an evening type, you're an evening type. It's hardcoded. We know that right now, there's at least 22 different genes that dictate what you are, morning type, evening type, or somewhere in between, and it's about a third/third split across the population. Why is it a split? Why are we nicely spread out across our chronotypes? For exactly the reason you described, because when we're in a tribe, if we all sleep at the same time, we're all vulnerable for eight hours. But if you were to insert some genetic variability into when people have a desire to sleep, you've got the morning types who maybe go to bed at 9:00 PM and are waking up, let's say, at 5:00 AM, and then you've got all of the extreme evening types who are going to bed at 2:00 AM and waking up at maybe 11 or midday. So, that way, the... everyone gets their eight hours of sleep, but the entire tribe, the nucleus of this group of Homo sapiens themselves, is only vulnerable for maybe just two or three hours. So, it's a clever solution that Mother Nature has come up with to say everyone gets their eight hours, but as a species, you're only going to be vulnerable for two to three hours max, when everyone, at least as a collective, is sleeping. Absolute genius.

5. 18:14 – 24:42

   Chronotypes/sleep deprivation

   1. MWMatthew Walker18:14

   2. SBSteven Bartlett18:14

      I used to think it was a load of nonsense, th- this chronotype thing. Um, it was actually on this podcast where I learned about its existence, and then I went on YouTube to learn more, and your video came up of you explaining it, because I thought... I always pondered why my partner goes to bed super early, wakes up super early, I go to bed late, wake up late. Um-... I'm gonna ask you th-this question actually 'cause it, 'cause I've, I've wondered this. In that situation where I'm sleeping in bed with a partner that has a different chronotype-

   3. MWMatthew Walker18:42

      Yeah.

   4. SBSteven Bartlett18:43

      ... it can have an impact on my sleep, right, because of the way that there are sleep cycles working, the REM sleep and the stage one deep sleep, et cetera, et cetera. If she's waking up when I'm pulling into REM sleep, i.e. if she's waking up at 5:00 AM, but at 5:00 AM because I've gone to bed later, my REM sleep has just begun, could... That has quite a significant impact on me, right? (laughs)

   5. MWMatthew Walker19:02

      Uh, if she is waking you up-

   6. SBSteven Bartlett19:04

      Yeah, if she's wake, if she wakes me up.

   7. MWMatthew Walker19:05

      ... then it's non-trivial, and likewise if you're waking her up as you're getting into bed-

   8. SBSteven Bartlett19:10

      Yeah.

   9. MWMatthew Walker19:10

      ... on the front end of sleep. So it's very difficult. One of the things that couples will cite if they break up, firstly, is usually about a third of them will cite sleep difficulties or sleep issues-

   10. SBSteven Bartlett19:25

       Really?

   11. MWMatthew Walker19:25

       ... as a, as a cause of the, their breakup, or at least as a contributing factor to that breakup.

   12. SBSteven Bartlett19:31

       One-third?

   13. MWMatthew Walker19:31

       Yeah.

   14. SBSteven Bartlett19:32

       Jesus.

   15. MWMatthew Walker19:32

       That it's one of, at least one of the factors. W-when you go then in, and when you double-click to say, "Okay, then what is it about this sleep kind of tension between the two of you?" One of those things is a mismatch in chronotype. And you can see this when, you know, people, I think this, you know, on dating profiles now, someone was telling me people even say, like, "I'm a morning type," or, "I'm an evening type," as if you're stating upfront, "This is part of my identity, and just FYI, be forewarned" because maybe it's been an issue for them in the past. This is why I often speak about the notion of what's called a sleep divorce to prevent a real one. (laughs) Now, it's not for everyone. Um, a sleep divorce is where you sleep in separate locations. And when we've surveyed people, um, both, uh, usually in the, from The Sleep Council in the United Kingdom, and also in the National Sleep Foundation here in America, w- the data is about the same. One in four people will say that they sleep in different locations with their partner, so a- almost a quarter of people in relationships will sleep in different locations. We think it's potentially an underestimate because if you survey people anonymously, then a third of them will report waking up, at least, in a different location the next morning. And part of the reason that it's a taboo is because people think, "Well, if I'm, if we're not sleeping together, then we're not sleeping together." The exact opposite is true, that when a couple is sleeping well, we know that the sex hormones are improved, testosterone in men, estrogen, um, and, uh, uh, luteinizing hormone in women. We also know that your, um, desire to be intimate with your partner is increased. Uh, what we found is that for an hour of extra sleep, if a woman gets an hour of extra sleep, her libido desire to be intimate with her partner increases by 14%. Now, to give you some context, the FDA drugs for improving or increasing libido in women, drugs such as Vyleesi here, clinical drugs, they will increase it by about 24%, and that's a pharmacological agent. But here, just the added non-pharmacological benefit of one hour of extra sleep will get you more than 50% of the way there. So, I want to just remove that notion of the stigma of that if you're not sleeping together, you're not sleeping. It's usually quite, quite the opposite. Um, I would say that part of the, the challenge though is that if we look at all objective measures, if I measure y- your sleep and the sleep of your wife, if, when you're sleeping separately versus when you're sleeping together, it's very likely that, objectively, you will both be sleeping worse when you're sleeping together. That's what the science tells us. However, what's interesting is that when you survey people and say, "How satisfied are you with your sleep?" which is a subjective measure, people will say, "I'm actually more satisfied with my sleep when I'm with my partner than when I'm sleeping alone." So, there's a mismatch here. Objectively, your sleep is better, but subjectively, you still prefer that... And of course, it's natural. You know, we, there is safety. There's security in co-sleeping. There is this sort of connection that we get. You, you can approach it if you want. Just be honest with yourself, and be honest with your partner, and you can start by saying, "Look, this isn't forever. I just want to say, let's do an experiment for a week, for 10 days. Let's, let's just try it and see how it goes, and it doesn't need to be permanent." Because what you actually miss are the bookends of sleep. For the most part, the two of you are not conscious for most of the experience of sleeping together. It's really getting into bed, and sort of having a kiss, or a cuddle, or, and sort of waking up together in the morning, and sort of dep-... Now, obviously, when you're a mismatched chronotype, that's also can be a challenge, too. So, you can still have a sleep divorce, but you can set up a, a system where you will go in, you'll say your good nights, and you'll kind of get into bed, have a kiss and cuddle, and then you retreat to a separate location, and you can repeat that same process. Um, so I, I don't want to sort of belabor the point of a, of a sleep divorce, but, um, people can certainly explore. There is something called a halfway house, which is called the Scandinavian method, which sounds far more salacious than it actually is. It's simply that you buy two beds (laughs) and you put them side by side in the same room, and therefore, the amount of disruption, physical, um, disruption that happens by way of sheets and movement, is decreased. But that doesn't solve it all. Sometimes there is snoring. Uh, sometimes there is sleep talking.

6. 24:42 – 30:44

   Will sleep get worse as we go on through life and society as we know it?

   1. MWMatthew Walker24:42

      Those things are not obviated by the Scandinavian method.

   2. SBSteven Bartlett24:46

      When you think about where society is, I was- I was- I was gonna ask you, you know, you said you wanted to- to do the work you're doing now for the rest of your life. Um, so do you think the work you are doing now is gonna become increasingly more important and relevant, i.e. is the problem gonna get worse-

   3. MWMatthew Walker25:02

      Hmm.

   4. SBSteven Bartlett25:02

      ... or is it gonna become less significant and less relevant based on the trajectory of society's you see it?

   5. MWMatthew Walker25:08

      Yeah. (sighs) You know, I'm mixed. I think when I wrote the book, uh, I was just writing, uh, the, uh, a book, uh, that was called Why We Sleep back in probably about 2014 or '15, and at that point, sleep was the neglected stepsister in the health conversation of that day. You know, we were speaking a lot about diet and exercise, which was wonderful, but there was no voice of sleep, and I was so sad about that because I could see so much disease and suffering that was coming so clearly by way of a lack of sleep, but it wasn't there on the public buffet menu for consumption of knowledge. And so, that was part of the motivation for trying to write the book. So, I would say now, and this is not because of me, or the book, or anything like that, but is- is sleep more of a conversation in this day and age than it was six or seven years ago? I think I would say yes, there is a greater awareness of- of sleep. Um, but with that awareness, I want- I think one can still question the pragmatic's meaning. Just because we're talking about it more does not mean that people are still failing to either get the sleep that they need or that they are unable to get the sleep that they need, and those two things are different. One is that you are healthy and you can generate the sleep that you need, but you don't give yourself the opportunity, time, or life, I should say sometimes 'cause it's sometimes not your choice. Life does not give you the chance to get sleep, and if only you had the chance, you could sleep. That's one version. The second version is now I'm giving myself the right opportunity to sleep, but because I'm anxious or because of other issues, I am not able to generate sleep. I suffer from insomnia and sleep problems. So, those two things, I don't see having changed since, you know, I think this public movement, this increasing movement of sleep conversation came on the table. So, in that regard, I'm more pessimistic than I am optimistic, and I think it will only get worse. If you look at rates of insomnia, for example, they're only increasing. They're only escalating. Rates of anxiety disorders, the very same thing, and those two things are intimately intertwined. So, I think I wish I- my mission was extinguished within the next couple of years because society started sleeping wonderfully well. I don't think that's going to be the case, so I think I've got my work cut out for me, um, to try and help people with better sleep. Um-

   6. SBSteven Bartlett27:56

      Is it... So, it's getting- w- we're getting worse at sleeping?

   7. MWMatthew Walker27:59

      I think modernity is making it v- so much more difficult for us to sleep.

   8. SBSteven Bartlett28:07

      Modernity. What's that?

   9. MWMatthew Walker28:08

      I think i- when you think about, you know, we often think about sleep as a biological process, and it very much is, and... But also, it's so environmental as well as biological, meaning when you were to say, you know, "How did you sleep last night?" think about all of the external factors that changed it. Well, I had to be up at this time. I had to catch a flight this time. My partner went to bed at this time, and she woke up at this time. There was this noise that sort of happened. I'm now sleeping in a hotel room. You know, there are countless externalities, and those externalities are shaped by this thing called the modern world. And in the modern world, if I could really be cynical, and I'm not someone, I'm very optimistic and I'm very non-cynical, but you could argue from a capitalistic standpoint that society does not want you sleeping because what society wants from a capitalistic point of view is that you're either producing or you're consuming, and when you're sleeping, you're neither producing and you're neither consuming. And so, there are lots of ways that I think society and m- the modern world has conspired, willfully or not, conspiratorially or not, to decrease and try to diminish sleep. In fact, I think the CEO of Netflix several years ago, and I'm sure that YouTube comments will correct me if I'm wrong here, but I believe his very statement was that, "We are- we are deciding to commit war against sleep." That was their goal.

   10. SBSteven Bartlett29:50

       Wow.

   11. MWMatthew Walker29:50

       And it just stunned me that, you know, that we're going to go to war with sleep. We're going to remove you from your sleep. So, there are lots of ways in- in which I think society does not help us. Light is another good example. We are a dark, deprived society in this modern era because we're exposed to light. We are not giving ourselves the right temperature cues. You know, we go into an office where it's, you know, 20 degrees or 70 degrees Celsius, whatever it is, stock stable, then we come home and we regulate our temperature at home to be the same thing. We take on board probably too much caffeine in this day and age, although I am actually an advocate of drinking coffee, and I can explain why, too. But anxiety, as I said, is a huge issue. All of these things are preventing and classic roadblocks to sleep.

7. 30:44 – 34:43

   How many of us are getting the right amount of sleep?

   1. MWMatthew Walker30:44

   2. SBSteven Bartlett30:44

      Um, how many of us are getting the sort of recommended daily allowance of sleep as a percentage, do you know?

   3. MWMatthew Walker30:51

      It seems to be about, um, one-third of...... most modern civilizations are failing to get the recommended seven to nine hours of sleep a night.

   4. SBSteven Bartlett31:03

      One-third, so r- roughly 30, 35%, 33% roughly?

   5. MWMatthew Walker31:07

      Yeah.

   6. SBSteven Bartlett31:08

      And it- it- does that have geographic variance, i.e., in some countries it's worse, in some countries it's better? I'm thinking about the UK versus the US or, you know, Japan, or whatever.

   7. MWMatthew Walker31:16

      Yeah, it is, and in fact, you, let me g- give numbers to the three countries that you've described. Uh, here in the United States, the average amount of sleep that people are getting is, uh, six hours and, uh, 29 minutes. In the UK, it's not much better, six hours and 49 minutes. Japan was the worst, six hours and 22 minutes. Now, to be clear, that's the average. What that means is that there is still a large proportion of that bell-shaped distribution of people getting even less than that amount. Now, there are some countries that you look at, um, that are actually sleeping much better than that. Uh, I think, let me, um, Mexico, uh, for example, is, um, is doing very well. If you look at Mexico City, uh, people are actually sleeping, uh, not too far off from eight hours. So, there is variability and we can try to understand why, which by the way just brings me back, while I think about it, to your comment of will my work be done, not from the, because I'm a scientist and I do, I have a- run a big sleep center at UC Berkeley, but the work I do as a, hopefully a public advocate for sleep, why I don't think it's going to change, um, any time soon, is because governments aren't really doing much about it, and I've tried as best I can, and if there is any government out there that listens to this that wants to work with me, I'd be delighted. I don't remember, and maybe you can, but any major first-world nation government that has had a public health campaign regarding sleep, and it stuns me, because those same governments have had public health campaigns regarding, you know, eating, regarding smoking, regarding drunk driving, regarding risky behaviors, safe sex.

   8. SBSteven Bartlett33:13

      Loneliness.

   9. MWMatthew Walker33:14

      Loneliness, mental health, suicide. Where is sleep in that equation? And it's such a fundamental ingredient, and in fact almost all of those things that I've just described have an intimate relationship with sleep. I mean, suicide especially, we were starting to do a lot of work with this, although it's been hard to get funding, but what we found is that insufficient sleep is a precursor to suicide, that sleep disruption seems to predict both suicide ideation, in other words suicidal thinking, suicide planning, and tragically, suicide completion as well. So, if we were to try to have governments create a public health campaign to pull this Archimedes' lever on better sleep, there are so many other health benefits. You know, sleep is the tide that rises all the other health boats. It's almost like a- it's like a mixing deck in a studio, you know, in those sound studios where you've seen it, and then there's that one button all the way to the end, the white button, sort of that when you move it up, sort of all of the other dials, the sort of, the red, yellow, orange, green dials, they all move up at the same time as well. There's this like- sort of one m- mess- there's like one ring to rule them all. Sleep is that Archimedes' lever, so if governments could only execute on that, the health benefits would be manifold in terms

8. 34:43 – 48:57

   Redesigning society to get better sleep

   1. MWMatthew Walker34:43

      of their consequences.

   2. SBSteven Bartlett34:44

      It begs the question, you know, if I were to make you today president, prime minister, whatever-

   3. MWMatthew Walker34:50

      (laughs)

   4. SBSteven Bartlett34:50

      ... of the world, and you had to do, you know, just a few things to really fix the lack of sleep epidemic, there you go, diagnosed it, um, what would those things be if you were in charge? How would you redesign society to help us to sleep better?

   5. MWMatthew Walker35:09

      Gosh, it's such a good question, and I've thought a lot about this, almost in reverse, which is to say, why is it that we are struggling to get sleep? And there is no single answer. There are so many different reasons, and that's why it's actually a very challenging problem to solve. I would go through a descending level of steps. So first, I would start at the government level, and we would get those public health campaigns in order. Um, next, I would go to the professional level, because there we have this mentality in business that, you know, sleep is for the soft among us, that s- less sleep equals more productivity, and that is just not true, and I can provide you with all of the evidence. So, we need to get rid of this sort of sleep machismo attitude in the workplace where we wear- wear our badge of honor of sleep deprivation on our arms. We need to get companies to actually start embracing sleep, and I can guarantee you and I can give you all of the evidence as to why, if as a company, as a CEO, if you start prioritizing the sleep of your employees, you will be far better off as a company. You will be more product-based, and you will be more profitable and revenue generating. Sleep is the very best form of physiologically injected venture capital that you could ever wish for, and in fact the Rand Corporation, which is an independent survey corporation, what they found is that at a national level insufficient sleep costs most nations about 2% of their GDP. So here in America that number was $411 billion of lost profit caused by insufficient sleep. In the United Kingdom, it was over $50 billion. In Japan, it was over $120 billion. If I could solve the sleep loss crisis in the workplace, I could perhaps double the healthcare benefit for many of those countries, or I could halve the e- the education deficit in those countries. So the next level I would target is...... at business. Then next step down would be medicine. Medicine is a classic demonstration here. We have junior doctors, or here in America, they have doctor residency programs where people are working 20, 30-hour shifts, and so already, doctors are inculcated into the mindset of the uselessness of su- of sufficient sleep. Across numerous countries, and I think it was maybe over eight different countries, we looked at the medical curricula, and we asked, "How many hours of education do doctors get about sleep?" And what's strange is that, you know, often doctors w- you'll go in and you'll have an appointment, they'll say, "Okay, you know, how are you eating? And, you know, what's going on with th- the bathroom? How's the toilet?" Um, and then, you know, "How are you sleeping?" As if sleep is one of these universal health barometers. But what we found is that most doctors will only be given about an hour to an hour and a half of sleep education during their entire medical school education, which blows my mind because it is one third of their patients' lives, but they're only given about 90 minutes of education. So no wonder your doctors aren't treating your sleep problems, thinking about your sleep problems, understanding your sleep. It's not their fault. And plus, they're sleep deprived anyway when they're being trained. Ironically, by the way, doctors, junior doctors who've worked a 30-hour shift, when they finish that 30-hour shift and get back in their car, they are 168% more likely to get into a car accident because of their lack of sleep, and end back up in the emergency room from where they were just working, but now as a patient. I mean, th- this, the paradox, the irony just stuns me. So I would next move down to the level of medicine, then I would go to education, because we don't get taught about sleep in schools. You know, I never got one of those special classes. You know, I got sort of, you know, sexual education classes, classes about drugs. No one came in and told me about the benefits of sleep. Why aren't we doing that? Then next, I would move down into the family, because there is prejudice in families with sleep. It's this notion of parents of teenagers, and these teenagers, by the way, it's not their fault, they have a shift in their chronotype, in their circadian rhythm, that when they go through puberty, when they're going through adolescence, they get fast-forwarded in time. So when they were eight or nine years old, they would be going to bed, you know, sort of early in the evening. But now as teenagers, they seem to be stubborn, and they're staying awake, staying awake until midnight, 1:00 AM, and they won't get into bed. It is not their fault, because they have a biologically wired shift in their tendency of when they want to wake up and when they want to sleep. Why am I bringing this up about this sort of mismanagement in the home? Because parents at weekends, they'll go into the room where the teenager is, they'll, you know, pull open the, the curtains, they will pull the covers off-

   6. SBSteven Bartlett40:25

      (laughs)

   7. MWMatthew Walker40:25

      ... and they say, "You're wasting the day." You know, and firstly, what they're doing is probably trying to sleep off a debt that we've lumbered them with during the week because of this incessant model of early school start times, which I'll, I'll come back to. But within the home, if you ask parents of teenagers what percent of parents think that their teenagers are getting sufficient sleep, and about 70% of them will say, "Yes, my teenager is getting sufficient sleep." When you look at the data, only about 15% of teenagers are actually getting the sleep that they need. So what happens is a parent-to-child transmission of sleep neglect. They're saying, "You're lazy, you're slothful." So then what happens? Well, in 15, 20 years time, now that teenager has got a teenage child. What do they do? They go back in the room, they rip the curtains open, they say, "You're wasting the day," because that's what they were told. So we need to break that down too, and then finally, we need to come to the individual, and we need to solve the individual's sleep problems. So it's a very long answer, and I'm desperately sorry, but to a very big question as to what I would do if I were czar for a day, but I hope that gives you some sense of, of the depth that I think we need to go to. I've tried to think about the question a lot. It's not particularly well executed. I don't think I was very eloquent there, but I hope that gives a sense.

   8. SBSteven Bartlett41:49

      It sounded perfectly eloquent to me. It sounded like a manifesto, so-

   9. MWMatthew Walker41:52

      (laughs)

   10. SBSteven Bartlett41:53

       ... um, hopefully if there are people listening from governments, which I'm sure there are, 'cause, you know, I hear about that sometimes, which is quite bizarre. But, um, I, I, I'm sure they'll be getting in touch with you very quickly. Going back to the top of that, that stack, on the company level, so as a CEO or a CFO or an employer, whatever, um, there are some companies that are incentivizing their team members to sleep, right? Is there any data showing the efficacy of that?

   11. MWMatthew Walker42:18

       There is data that we have, and it's bidirectional, both the efficacy of when you increase sleep-

   12. SBSteven Bartlett42:26

       Mm-hmm.

   13. MWMatthew Walker42:26

       ... and also the detriment when you don't allow sleep. So a great example was, um, NASA back in the 1980s, they were looking at using naps in their astronaut program, because when you're up and you're orbiting Earth, you will actually be cycling Earth, uh, you know, really quite quickly, and you will get to see, depending on the orbit, maybe somewhere between 10 to 15 sunrises every 24 hours, which sounds, I mean, a-amazing and remarkable, but trust me, in terms of your sleep, it is very dislocating. So they were looking at how to use naps strategically to improve performance, because the weakest link on any space mission, and we've d-done some work with NASA, um...... is the human being themselves, and they can cause catastrophic failure. Now, if you make an error at work and you're here terrestrially on the ground, you know, it's probably non-trivial. (laughs) Make an error when you're up in space, i- i- it can be a big deal. So they were looking at that, and what they found was that these naps, anywhere between 20 minutes to an hour, could increase productivity on these different tasks by about 34% and increase general alertness by over 50%. And in fact, the data was so powerful that it ended up being transmitted to all of the terrestrial workers on the ground, that NASA would start to int- it- it was what we called NASA naps. It was a NASA nap culture. Now, NASA isn't desperately compassionate by any means. It's a great organization, but they, just like companies like Google or Facebook, they understand the pounds and pennies, cents, you know, the dollars and the cents version of productivity. So anything that returns productivity, they will invest in. And some of those companies, you know, I, um, I did some work at Google, uh, during a sabbatical, and there on their campus, they will have these nap pods and they will have these what are called Shh Rooms, where you can go and you can take a nap. So think about 20 years ago, you would never imagine a company paying you to sleep on the job. If you were caught sleeping on the job, you'd probably be fired. Now companies are incentivizing it, not because they are thinking compassionately or empathetically about the health or the wellness of their individuals. It is because they understand that it transacts marked productivity. So NASA was a good example. When you give sleep, you get something back. But I can go back to the reverse of that. Why we think that a lack of sleep does not equal more productivity is for at least five reasons. First, when you survey, and we've, we can do these studies in the, in the laboratory too, when you under-sleep employees, they will choose less challenging problems. So if you give them an array of work problems, they will just simply, you know, check email, they'll listen to phone messages. They don't dig into deep project work. Second, of the problems that they do take on in their work, they will produce fewer creative solutions, and after all, creativity and ingenuity are supposed to be the two engines that drive businesses forward in terms of their productivity and their revenue. The third that, uh, interesting finding that we've discovered is that when under-slept employees start working in teams, they will slack off. They won't do their work. They will let other people do their work. It's what we call social loafing.

   14. SBSteven Bartlett46:07

       Hmm.

   15. MWMatthew Walker46:07

       So they ride the coattails of other people's hard work, which won't breed a good atmosphere in your company. You know, trust me. The fourth thing that we found is that under-slept employees are more deviant, that they're more likely to fudge data in spreadsheets, they're more likely to falsely claim, uh, money for reimbursement that was inappropriate. The final thing is that a lack of sleep will go all the way to the top of the business chain. What we found is that the more or less sleep that a business leader has had from one night to the next to the next, the more or less charismatic their employees will rate that business leader from one day to the next to the next. Even though the employees themselves, they know nothing about the sleep that that CEO has been getting, it's evidential in how charismatic that CEO is. So you can add all of these things up, and no wonder, you know, if you don't snooze, you lose in the case of business in that regard.

   16. SBSteven Bartlett47:11

       (laughs)

   17. MWMatthew Walker47:11

       That's why I can produce, I think, a non-trivial case for business. By the way, the other aspect that is hugely costly to businesses, and when I go and speak to businesses about why they should value sleep, if you offer it on the grounds of, again, sort of compassion or mental health, they probably don't want to listen. When you convert it into the cost to the company and how much it's fleecing them in terms of their prof- profits, then they start to pay attention. Under-slept employees will take, on average, about 11 more days, uh, sick days throughout the year relative to well-slept individuals. So you're essentially just paying people additionally for 11 days of work that they will never give you when you are under-sleeping them. Secondly, their utilization of healthcare resources increases by about 80%, so the cost to either you, the company here in the US, where your company is paying for your healthcare, or the cost to the government, for example, in the United Kingdom, is astronomical. And also then, the co- what we call comorbid diseases, your rates of obesity, diabetes, cardiovascular disease, mental health conditions, all of these things escalate as under-slept employees continue to get even more under-slept. So there is no strong case that I've seen that leads me to think businesses should foster the mentality of insufficient sleep. Quite the opposite. So that's ho- hopefully an answer to your question. We can look at it bi-directionally. When we give sleep back, do you get productivity? Yes. When you take sleep away, do things implode rapidly? Yes. And is it costly to your company? Very

9. 48:57 – 56:16

   Napping

   1. MWMatthew Walker48:57

      much so.

   2. SBSteven Bartlett48:58

      On that point of naps, and you know, Google, sleep pods, naps, and things like that, there was a point in my life where I, because I learnt about REM sleep and the importance of REM sleep and deep sleep, and that happens a little bit further on into my, you know, the 90-minute... Look at me trying to tell a sleep expert scientist about it.

   3. MWMatthew Walker49:15

      (laughs) No, I love it. Yeah.

   4. SBSteven Bartlett49:16

      But do you see what I mean? Like, this is my very, this is my monkey brain, so I didn't understand the subject matter very well. Still really don't, to be honest, but in the first n- it takes me a s- significant amount of time to get to deep sleep, into REM sleep.... how long wou- on average wo- would you say it takes? For a, for s- you know.

   5. MWMatthew Walker49:32

      Yeah, so you will probably go into light sleep in the first 10 to 15 minutes.

   6. SBSteven Bartlett49:37

      Yeah.

   7. MWMatthew Walker49:37

      Then you'll go down into deep sleep, you'll stay there for about 30, 40, uh, minutes, then you'll start to rise back up, and you'll pop up and you'll have a short REM sleep period, and then you complete the non-REM to REM cycle after about 90 minutes, and back down you go again, down into non-REM and up into REM, so on average for human beings, it's 90 minutes.

   8. SBSteven Bartlett49:58

      So, I therefore assumed that napping really does nothing, because I thought, "Well, it takes me so long to get to REM sleep-"

   9. MWMatthew Walker50:05

      (laughs)

   10. SBSteven Bartlett50:05

       "... and to deep sleep, that there's n- if I've got 15 minutes, 20 minutes, to, to nap, it's just a waste of time."

   11. MWMatthew Walker50:11

       Right.

   12. SBSteven Bartlett50:12

       Was I wrong or was I right?

   13. MWMatthew Walker50:15

       You were understandably wrong.

   14. SBSteven Bartlett50:18

       Okay, good.

   15. MWMatthew Walker50:20

       (laughs)

   16. SBSteven Bartlett50:20

       I'm happy because I, I've always rejected naps because I thought they don't matter-

   17. MWMatthew Walker50:24

       Yeah.

   18. SBSteven Bartlett50:24

       ... because it takes me so long to get to a restorative state anyway, so.

   19. MWMatthew Walker50:27

       So we've done lots of different studies with naps, we and other colleagues, uh, too, and what we've found is that naps can transact some fantastic benefits. They can improve cardiovascular health, lower pro- uh, blood pressure, they can improve your learning and memory abilities, they can reset the emotional north of your magnetic compass in a good way where you can deescalate negative emotions and increase positive emotions, um, so naps certainly are a good thing but with a big caveat that I'll come back to. Um, yes, you're right in the sense that to get a full cycle of sleep and to get into REM sleep, you would probably have to make that nap about 90 minutes, and in fact a lot of the studies that we do, we will use a 90-minute nap duration of time so that the brain can cycle through all of those different stages of sleep, but you don't need to nor would I suggest that you do. What we found is that different stages of sleep perform different functions for the brain at different times of night. There are actually four separate stages, stages one through four, increasing in their depth of sleep, so stages three and four are those really deep stages of non-REM sleep. Stages one and two, that's the lighter form of non-REM. And then you have rapid eye movement sleep or what we think of as dream sleep. And people will sometimes say to me, "How do I get more REM sleep?" Or, "How do I get more deep sleep?" And my response to them is, "Why do you want to get more REM sleep?" And their answer is, "Well, isn't that the good stuff?"

   20. SBSteven Bartlett52:05

       Yeah (laughs) .

   21. MWMatthew Walker52:05

       (laughs) And it turns out that there is no good stuff. It's all good stuff, you know, maybe with the exception of that light stage one non-REM sleep, that's shallow sleep, and we typically don't like to see too much of that, but stage two non-REM sleep, three and four, they all have their different functions that we've discovered, and REM sleep has its functions, so you need all of them. You can't short, sho- shortchange any of them. But for a nap what we found is that you can get th- nice benefits for things like your learning and your memory and it can even reduce some level of anxiety up to about 20 minutes. You can, in fact, you can nap, I think the study, one of the studies, they brought a nap down to about nine minutes in duration and there were still some basic improvements for your sort of general level of aler- alertness and reaction time. For example, if you're an athlete, that's, that's non-trivial. So, um, so the reason I would say be careful with naps is for two main, um, sort of suggestions. The first is try not to nap for about longer than 20 minutes because once you go past 20 minutes, you really start to go down into those deeper stages of non-REM sleep, and if you wake up after about 45 minutes or 60 minutes, that's not a problem. I'm not suggesting that you shouldn't or you couldn't. I'm just saying be aware because when you come out of that deep sleep and you wake up from that deep sleep, normally that's not how you wake up. You will usually wake up out of lighter stages of sleep or out of REM sleep. It's rare that we wake up out of deep sleep. But if you nap and you nap for about 40 minutes, you'll probably go down into deep sleep, and at that point where if you wake up and your alarm goes off, then you're going to feel almost miserable and worse than you did before the nap because you have what's called sleep inertia which is essentially a sleep hangover where the brain is still sort of pulled back into that deep sleep state and it can take you almost an hour before you feel like you're back up to operating temperature and you're up to motorway speed.

   22. SBSteven Bartlett54:12

       Mm-hmm.

   23. MWMatthew Walker54:12

       So, I would say keep it to 20 minutes and you don't suffer too much of that inertia. You still get some nice benefits. Also, don't nap too late in the afternoon. Also, the final part is if you are struggling with sleep at night, if you're someone who has insomnia or sleep difficulties, do not nap during the day. It's the worst thing that you can be doing, because when we're awake during the day, we build up a sleepiness chemical in our brain. It's called adenosine, and the longer that we're awake, the more adenosine that builds up. The more adenosine that builds up, the sleepier and sleepier that we feel, and when we sleep, the brain gets the chance to clear away all of that adenosine, all of that sleepiness, and somewhere between seven to nine hours after sleeping a full night, the brain has evacuated all of that sleepiness chemical, all of that adenosine so that then we should wake up and we should feel refreshed and restored and not needing caffeine to, to function. Why is that relevant to naps? Well, it's relevant to naps because when you take a nap, you're essentially, it's like a pressure valve on a cooker. Pshh. You're just releasing some of that healthy sleepiness that you've been building up, and therefore if you are struggling with sleep at night and then you nap during the day, it's terrible because you're taking away all of that healthy good weight of sleepiness...... that we've been trying to build up on your shoulders to give you the best chance of a good night of sleep. That's why I would say if you are suffering from insomnia, don't nap during the day. Also, even if you are, if you don't struggle with sleep at night, try not to nap after about 3:00 PM in the afternoon or 2:00 PM. Napping late in the afternoon or in the early evening, it's a little bit like snacking before your main meal. It just takes the appetite off your sleep hunger, so try not to do that. But naps, for the most part, if you don't struggle with sleep, they are wonderful things. Just keep in mind the 20-minute sort of idea.

10. 56:16 – 1:09:51

    Caffeine

    1. MWMatthew Walker56:16

    2. SBSteven Bartlett56:16

       You mentioned caffeine there, a topic I've mulled over, over and over again on this show.

    3. MWMatthew Walker56:22

       (laughs)

    4. SBSteven Bartlett56:22

       Um, because as I've said to, uh, maybe three or four of my guests now, it feels like caffeine is a miracle drug that comes with no apparent cost. But when I think about things like anxiety, and I know shallow sleep states, I've always pondered that maybe caffeine is playing a role in that. You said you- you're, you're pro-caffeine, you're a caffeine drinker yourself.

    5. MWMatthew Walker56:43

       So I am not a caffeine drinker myself, but I am pro-coffee.

    6. SBSteven Bartlett56:48

       Oh, okay.

    7. MWMatthew Walker56:49

       Uh, and I'm, I'll tell you why I'm very thoughtful about my wording between caffeine and coffee there, and to your point, it's a, it's another astute one which is, it w- you know, is it a miracle drug with no cost? In biology and medicine, there is almost no free lunch (laughs) , um, and that is true when it comes to caffeine and sleep. So, perhaps I'll give the skinny on caffeine and how it impacts your sleep, but then circle back around to what seems an oxymoronic statement for me, which is why I'm still pro-coffee. Um, caffeine will hurt your sleep in probably at least three ways, some of which you, most people are not aware of. The first issue is the duration of its action. So caffeine has what we call a half-life of about five to six hours. In other words, after about five to six hours, half of that caffeine is still in your system. What that means is that caffeine has a quarter-life of somewhere between 10 to 12 hours, so if you have a cup of coffee at noon, at midday, a quarter of that caffeine is still in your brain at midnight. So having a cup of coffee at noon, and it's hyperbole in truth probably, or it's a little bit hyperbolic, but it's almost the equivalent of a coffee at noon is the equivalent of, you know, tucking yourself into bed, and just before you turn the light out, you swig a quarter of a cup of coffee, and you hope for a good night of sleep. (laughs) And it's probably not going to happen. So that's the first thing to keep in mind is the, the timing of, of caffeine. The second is that caffeine is a stimulant. Now everyone knows this. Everyone knows that caffeine can make you more alert and more awake. By the way, how does it do that? Um, it comes back to adenosine, which is the chemical that we spoke about, the sleepiness chemical. It's no coincidence that those two things sound the same at the end of the name, caffeine and adenosine. Caffeine will actually race into your brain, and it will latch onto the adenosine receptors, the welcome sites in your brain. And it has very sharp elbows, and it will force away the adenosine from those receptors, and it will hijack those receptors. Now at this point you may be thinking, "Well, hang on a second, if it's latching onto those sleepiness chemical receptors, shouldn't caffeine make you more sleepy?" And the answer is no, because what it does is it just latches onto the receptor, and it inactivates it essentially, so it masks the receptor. What caffeine does then is race into your brain. You've got all of this sleepiness at 9:00 PM or 10:00 PM, you have an espresso 'cause you're trying to power through and finish the report or, you know, the presentation for your sort of, your pitch, uh, f- deck for your startup company, and that caffeine races in, it latches onto the adenosine receptors, and blocks the signal of adenosine. So now your brain was thinking, "I'm starting to get tired, it's 10:00 PM," but now all of a sudden that signal is blocked, and it, caffeine is like hitting the mute button on your television remote controller. It just mutes the signal of sleepiness. So now you think, "Well, now, I don't feel sleepy anymore." And here's the danger, that even though, well, when the caffeine is in your system and it's latched onto the receptors, that adenosine is still there. It's not going away. In fact, if anything, during the course of the caffeine in your system, it continues to build and build, and now when the caffeine finally gets metabolized and excreted out of your system, not only do you go back to the sleepiness that you had many hours before, it's that plus all of the adenosine sleepiness that's been building up during that time in between, so you get hit with this huge tsunami wave of sleepiness, and that's what we call the caffeine crash. So the, one of the issues, so that's sort of caffeine in terms of how it works and its timing. Another issue is that it creates anxiety, just as you said, and anxiety is probably one of the greatest enemies of sleep. It's one of the principal reasons that underlies insomnia is a physiological state of anxiety, that your fight or flight branch of the nervous system is ratcheted up. That's what caffeine will do. It needs to do the opposite for you to fall asleep. That's why you can have what we call the tired but wired phenomenon, where you say, "I'm so desperately tired, I am so tired, but I'm just so wired that I can't fall asleep." It's because your nervous system is too amped up. Caffeine will trigger that amping up. Then at that point if you're struggling to fall asleep 'cause you've got too much caffeine on board, it is what we call anxiogenic. So now you start to worry.... and the last thing you need to do when your head hits the pillow for good sleep is worry, because when you start to worry, you start to ruminate, and when you ruminate, you catastrophize, and when you catastrophize, you're dead in the water for the next two hours when it comes to sleep. Because we have this sense that, you know, things at night, in the darkness of night, are so much bigger than they are in the brightness of day, and we start worrying. You know, in this modern era, we're constantly on reception and very rarely do we do reflection. Unfortunately, the only time when we typically do reflection is when we turn off the light and our head hits the pillow, and that is the last time you wanna be doing reflection. So that's the, uh, the second problem with caffeine, it's anxiogenic, and it only makes you sort of almost like the Woody Allen neurotic of the sleep world. The final part of caffeine is that it's very good at blocking your deep sleep. So we've done a number of these studies where we'll give people a standard dose of caffeine, let's say 150 milligrams, 200 milligrams, which is probably, you know, a cup and a half of good strong coffee, and then we put you to bed, and we look at the amount of deep sleep, and it will strip away your deep sleep by about somewhere between 15 to 30%. Now to put that in context, to drop your deep sleep by 30%, I'd probably have to age you by about 40 years, 4-0, or you could do it every night with an espresso with, with dinner, and that's one of the problems. People will say to me, "Look, I'm one of those people who I can have two espressos with dinner, and I fall asleep fine, and I stay asleep, so no harm, no foul." Well, not necessarily, because even if you fall asleep and you stay asleep, you're not aware of the lack of the deep sleep that you're not getting because of the caffeine. And so now you wake up the next day and you think, "Well, I don't remember having a hard time falling asleep. I don't remember waking up, but now I'm reaching for two or three cups of coffee the next morning rather than my standard one cup of coffee because I don't feel refreshed and restored by my sleep because I was lacking the amount of deep sleep."

    8. SBSteven Bartlett1:03:51

       And deep sleep, what does that rob us of, the lack of deep sleep?

    9. MWMatthew Walker1:03:54

       So lack of deep sleep... Deep sleep is critical for regulating your cardiovascular system. It's the time when we do replenish the immune system. It also regulates your metabolic system, so it controls the hormones such as insulin that will regulate your blood sugar, and you will become blood sugar dysregulated without sufficient deep sleep. Upstairs in the brain, deep sleep will, um, strengthen, and consolidate, and secure new memories into your brain. They will prevent those memories from being forgotten. Deep sleep is also the time when we cleanse the brain of metabolic toxins, particularly the toxins that are related to Alzheimer's disease. So getting a lack of deep sleep is, I would say, a non-trivial thing, um, in that regard, but I don't want to be all so puritanical here, and this is where I'm going to change my title tune. I am not here to tell anyone how to live their life. I have no right to tell anyone how to live their life. I'm just a scientist. All I want to try and do is gift you the science and the knowledge of sleep so that you can make an informed choice. And after all, and the same is true for alcohol too and sleep, you know, life is to be lived to a certain degree. You know, no one wants to be the healthiest guy in the graveyard. (laughs) I don't want to be that way too. I want to live life, just w- with moderation. The reason I don't drink, uh, caffeine is not because, uh, I'm so puritanical I want to be the poster child of good sleep. I love the smell of freshly ground coffee in the morning. Uh, it's a great ritual. It's just that I've run my genetics, and I am one of the slow caffeine metabolizers. So you can do these genetic kits online and they will tell you, are you a slow metabolizer or a fast metabolizer? Uh, so that's the variability. That's why some people say, "Look, I'm pretty immune to caffeine," and others will say, "No, I'm not." Um, why do I now favor coffee? I was re- actually quite anti-caffeine-in-coffee when I first came out with the book just looking at studies, but now the data is immensely compelling. The health benefits associated with coffee are undeniable, study after study after study, and we can put them all together in this big what we call a meta-analysis study, and it is so strikingly clear that coffee, drinking coffee, is a good thing for you from a health perspective. Two things to say about that. The first is that it's got nothing to do with the caffeine, and a lot of people have sort of rightly challenged me to say, "Look, you say how problematic sleep can be when you're drinking too much caffeine, but yet coffee is associated with many of the same health benefits that sleep is associated with, but coffee is supposed to hurt your sleep. How do you reconcile those two, (laughs) Matt Walker?" And the answer is very simple: antioxidants. Because it turns out that the coffee bean contains a whopping dose of antioxidants, things such as, uh, it's, well, it's got other things such as cafestol, but it's got a bunch of incredible antioxidants. Probably the most powerful of them in terms of the coffee bean is something called chlorogenic acid. Now don't worry, it's not chlorine, it's not chloride, it's not bleach. Chlorogenic acid is very different. And what's happened in the modern world is that we un- uh, we have... and struggle with our diet so much because we don't eat enough whole foods, et cetera. So what's happened is that the coffee bean has been now asked to carry the Herculean weight of all of our antioxidant needs on its shoulders.... and where most people get the majority of their antioxidants is by way of drinking coffee. That's why coffee is associated with so many health benefits, and it's not the caffeine. Case in point, if you look at the studies with decaffeinated coffee, you get very similar health benefits.

    10. SBSteven Bartlett1:08:07

        Mm-hmm.

    11. MWMatthew Walker1:08:08

        Again, it's not the caffeine. It's the coffee itself, so the bottom line here is drink coffee, but I would say the dose and the timing make the poison. So, try to limit yourself to about two cups of coffee, three cups of coffee maximum, because if you look at the health benefits, by the way, it's a dose... it's not a dose response, where it linear, where the more and more coffee you drink, the more and more healthy you become. It peaks at about two to three, and then actually starts to go down in the opposite direction for lots of reasons that we could speak about. So, dose and the timing make the poison when it comes to coffee.

    12. SBSteven Bartlett1:08:44

        So you drink decaf?

    13. MWMatthew Walker1:08:45

        So, I do drink decaf.

    14. SBSteven Bartlett1:08:47

        Okay

    15. MWMatthew Walker1:08:47

        So, I will drink coffee just because I love the smell and I do enjoy the taste of it, but I drink, uh, decaffeinated coffee. I would love to drink, uh, caffeinated coffee too 'cause I... You know, I'm, I'm sure it would be interesting 'cause I work out every day and I work out every morning, and so many of the health coaches that I speak with and health professionals say, "You know, you should definitely get a shot of caffeine in and it'll boost your workout." And actually, the data on that is pretty clear too, that y- your lifting, for example, in the gym, and your metabolic activity is stronger when you've had pre-caffeine doses.

    16. SBSteven Bartlett1:09:22

        But it's also stronger when you sleep, so...

    17. MWMatthew Walker1:09:24

        But... Exactly, and that's the problem. So, uh, and sleep is, I would argue, much more beneficial to health, and if you're trying to work out or you're trying to, uh, be an athlete or perform, sleep will trump caffeine five ways till Tuesday. I mean, sleep is probably the very best legal performance-enhancing drug that we know of that not enough athletes are abusing.

11. 1:09:51 – 1:10:51

    Ads

    1. MWMatthew Walker1:09:51

       (laughs)

    2. SBSteven Bartlett1:09:51

       As you might know, this show's now sponsored by Airbnb. I can't count how many times Airbnbs have saved me when I'm traveling around the world, whether it's, you know, recently when I went to the jungle in Bali or whether it's when I'm staying here in the UK or going to business in America. But I can also think of so many times where I've stayed in a host's place on Airbnb, and I've been sat there wondering, "Could my place be an Airbnb as well? And if it could be, how much could I earn?" It turns out you could be sitting on an Airbnb goldmine without even knowing about it. Maybe you have a- a spare room in your house that friends stay from time to time. You could Airbnb that space and make a significant amount of money instead of letting it stay empty. That in-law, that guest house, that annex where your parents sometimes stay, you could Airbnb that and make some extra income for yourself. Whether you could just use some extra money to cover some bills or for something a little bit more fun, your home might be worth a little bit more than you think. And you can find out the answer to that question by going to airbnb.co.uk/host.

12. 1:10:51 – 1:14:02

    Sleep medication

    1. SBSteven Bartlett1:10:51

       One of the other sort of ongoing stereotypes that I've always wondered if it was wrong or right or whatever, now I get to... A chance to ask you, is about this culture of sleep medication. So, I've got some friends who, who might have, I don't know, prescribed sleep medication, but I've got a lot of friends also that use what they call sort of natural... They always use the word natural.

    2. MWMatthew Walker1:11:10

       (laughs)

    3. SBSteven Bartlett1:11:10

       Natural something s-... So it's like natural sleep tablets.

    4. MWMatthew Walker1:11:14

       Yeah.

    5. SBSteven Bartlett1:11:14

       What's your perspective on this culture of as- of humans taking sleep tablets to get them to feel sleepy and go off to sleep at night?

    6. MWMatthew Walker1:11:22

       Usually, when people ask me that question personally, I- the first thing I ask them is, "Why is it that you think you're not able to sleep?" And try to reverse engineer the question from there. Before we even start thinking about sticking Band-Aids on wounds, I firstly want to ask what's causing the infection because we can keep bandaging it for all we like, but if it keeps festering, it's probably not going to go away anytime soon.

    7. SBSteven Bartlett1:11:48

       Is it a problem to keep bandaging it?

    8. MWMatthew Walker1:11:50

       It is a problem. Right now, we don't typically advocate sleeping pills as the first-line defense agent against or for insomnia as a treatment. In fact, in 2016, the American Coll-... And again, this is me simply describing the science. This is me being descriptive of the science, not prescriptive in terms of medicine 'cause I'm not a medical doctor. Um, but in 2016, the American College of Physicians, they had a expert panel who surveyed all of the literature on classic sleeping pills, and what they suggested was that sleeping pills must no longer be the first-line treatment for insomnia. It has to be cognitive behavioral therapy for insomnia or what we call CBT-I, which is a psychological intervention that we can speak about. But their recommendation was that they found... I think their wording was, um, small and of questionable clinical importance in terms of the benefits of sleeping pills. Now, there is a time and a place for- in clinical medicine for sleeping pills but usually as an adjunct w- in combination with cognitive behavioral therapy. They are not advocated for long-term use, but... So they're usually advocated for short-term use, weeks. Most people are... Have been on them for months, if not years, these classic sleeping pills, and that's a problem because those sleeping pills are in a class of drugs that we call the sedative-hypnotics, and sedation is not sleep. For some subset of some people, there are some of these, quote-unquote, "sleep supplements" that may benefit, but overall, the studies are very clear none of them are efficacious, and when you think about it, it makes sense. You know, if there was some cheap sleep supplement that you could buy on Amazon that was the Shangri-La of good sleep, that was this miracle sleep drug-... don't you think that a pharmaceutical company would have patented it 20 years ago and be making billions of dollars from it? You know, that alone tells you all that you need to know about, you know, these natural sleep supplements.

13. 1:14:02 – 1:16:16

    CBT for sleep

    1. MWMatthew Walker1:14:02

    2. SBSteven Bartlett1:14:02

       Cognitive behavioral therapy for insomnia, though-

    3. MWMatthew Walker1:14:05

       Yeah.

    4. SBSteven Bartlett1:14:05

       ... seems to be the kind of, the front line of prescribed defense against a lack of sleep, insomnia conditions. What exactly is that therapy aiming to do? What, like, what does it do for, for somebody?

    5. MWMatthew Walker1:14:17

       Great question. So, in some ways, the, the title, um, tries to suggest what it, what it does, but not particularly well, perhaps. So, it focuses on cognitive aspects and it focuses on behavioral aspects. So, for the cognitive aspects, when we do cognitive behavioral therapy, working with a patient, we will try to focus on thoughts and beliefs and ideas around sleep. Do they have anxiety around the bedroom? Most of them do, be-

    6. SBSteven Bartlett1:14:45

       "I can't sleep."

    7. MWMatthew Walker1:14:46

       "... because I can't sleep, so every time I walk into the bedroom, my bed is the enemy, and I look at the bedroom and I look at the bed, and I just know that that means I'm gonna have a bad night of sleep." So what's happened is that at that point, your sleep controls you, and you've lost all confidence in your ability to sleep, and we need to course-correct that. So one of the things we do in cognitive behavioral therapy is that we lower that anxiety and we say, "Look, everyone has a bad night of sleep, even a bad couple of nights of sleep." In fact, I will tell you, I don't sleep perfectly well all the time too. I've had at least two very severe bouts of insomnia in my life. We all have a bad night of sleep. It doesn't mean that tomorrow you're going to wake up with depression or Alzheimer's disease. Don't worry, you're not going to get cancer, you know, to m- just because you've had a bad night of sleep. So we start to change people's misbeliefs about sleep, and we try to get them back from being catastrophic about this idea of m- my not sleeping. So we... That's the cognitive aspect. We start to lower their anxiety around the bed and, and the bedroom. We start to try to build confidence back. We start to reduce their expectations about, you know, what is reasonable sleep? Well, right now, you're getting four or five hours of sleep, and we can do better, but don't start thinking that you need to get eight hours of sleep straight out the box. Let's just manage it.

    8. SBSteven Bartlett1:16:12

       That's just because it's gonna stress you out, right?

    9. MWMatthew Walker1:16:14

       It's only gonna make matters worse.

    10. SBSteven Bartlett1:16:15

        Right. Okay.

14. 1:16:16 – 1:19:23

    What to do when you're struggling with sleep

    1. SBSteven Bartlett1:16:16

    2. MWMatthew Walker1:16:16

       You know, when you're struggling with sleep in the middle of the night and you're wide awake.

    3. SBSteven Bartlett1:16:20

       You're laying in bed and you're thinking, "Oh my God, I've got five hours left before I've got to go to work."

    4. MWMatthew Walker1:16:23

       It's terr- it's the last... You know, it's a little bit like trying to remember someone's name.

    5. SBSteven Bartlett1:16:27

       Mm-hmm.

    6. MWMatthew Walker1:16:27

       The harder you try, the further you push it away.

    7. SBSteven Bartlett1:16:31

       So would you say in that si- what, what do I do in that situation? You... It's 2:00 AM in the morning, you've gotta be up at 7:00. There's a flight you're getting on, so whatever.

    8. MWMatthew Walker1:16:38

       Yeah.

    9. SBSteven Bartlett1:16:38

       What should one do? 'Cause from what I was reading in chapter 14, I was, I was hearing that maybe I should get out of bed-

    10. MWMatthew Walker1:16:45

        Yeah.

    11. SBSteven Bartlett1:16:46

        ... or not just sit there and ruminate, you know, into the early hours of the morning. Or do I stay in bed and do something? What does one do?

    12. MWMatthew Walker1:16:54

        The prototypical recommendation is that after about 30 minutes of time awake, you should get out of your bed, and you should just go to a different room and do something like, you know, read a book or listen to a podcast. Don't eat, 'cause it then trains your brain to wake up to, to do that. Don't start working or getting in front of a computer screen, you know. I said listen to a podcast. Sure, you know, just make sure your phone's in. You know, you don't start scrolling any more than that. But you can do relaxing things, stretch, meditate. The reason is because if you start to spend a lot of time awake in your bed, your brain is an incredibly associative device, and very quickly, it will start to learn that this thing called your bed is this place where I'm always awake, and therefore, you start to learn through this r- repeated loop of behavior that I'm always going to be wide awake in bed. And we need to break that association, and that's why we say get out of bed after about 30 minutes, 'cause you're just training your brain to think that this thing called my bed is the place where I'm never asleep, and we want to break that. And only return to bed when you're sleepy, and there's no time limit for that. And that way, gradually, it's much better because you will relearn the association that your bed, just as when you were young, you've guaranteed that your bed is this place where you will always be asleep. The problem with that is many people don't want... You know, it's the middle of the night, it's dark, it's cold. "I- I'm not, I'm just not going to get out of bed." So what's your other... What e- what else (laughs) have you got in your toolbox, Matt? Um, at that point, I would say, "Okay, that's reasonable." The first thing I would suggest is meditation. You know, I am a hard-nosed scientist, and when I was researching that for the book, I was, you know... I just thought, "This sounds all a bit woo-woo," and, you know, I, uh, live and work in Berkeley, California, which is kind of, you know, the free speech, you know, flower power movement, San Francisco, flowers in your hair business. I just thought, "This is all a bit, you know, holding hands and singing Kumbaya." You know, this is, this is not for me, this, this meditation stuff. I couldn't get away from the strength of the data. It was immensely powerful regarding sleep and its benefits on insomnia and sleep. So I started meditating, and, uh, now I meditate for 10 minutes before bed every single night, and I've been doing that for about four years. So I would say if, even if it's in the middle of the night, and if I wake up in the middle of the night, I'll start to try to walk myself through a meditation. Um...

    13. SBSteven Bartlett1:19:22

        Y-

15. 1:19:23 – 1:26:06

    Listening to something before bed

    1. SBSteven Bartlett1:19:23

       you reference there listening to podcasts, et cetera, et cetera, you know, doing something else to stimulate the brain. I, when I go to bed, I have to have something playing. I say have to, I shouldn't be that definitive. I like to have something playing, some kind of sound or noise, whatever, and much to my partner's dismay-

    2. MWMatthew Walker1:19:41

       (laughs)

    3. SBSteven Bartlett1:19:41

       ... my (laughs) content of preference is serial killer (laughs) -

    4. MWMatthew Walker1:19:47

       (laughs)

    5. SBSteven Bartlett1:19:48

       ... podcasts or documentaries, or just like-

    6. MWMatthew Walker1:19:50

       Right.

    7. SBSteven Bartlett1:19:50

       ... something which is really gonna grab hold of my brain.... and focus me. So something like, it has to be really interesting to me for me to be able to focus on it. My partner is the opposite, again. She likes, um, silence. Why do I listen to serial killers?

    8. MWMatthew Walker1:20:08

       It's different for different people's constitutions-

    9. SBSteven Bartlett1:20:10

       Yeah. (laughs)

    10. MWMatthew Walker1:20:11

        ... yeah, uh, type psychologies. Uh, and, uh, you know, I can pathologize you all you like if, if you would wish me to-

    11. SBSteven Bartlett1:20:17

        (laughs) .

    12. MWMatthew Walker1:20:17

        ... but I would say, it, it, what's fundamentally going on here with meditation, uh, and I'll come back to an alternative too, but the reason why some meditation apps as well have now started to do what's called sleep stories, which in some ways is what you're doing-

    13. SBSteven Bartlett1:20:33

        Mm-hmm.

    14. MWMatthew Walker1:20:33

        ... a version of with your podcast, is, harks back to when we were kids. You know, for many parents, they would just read a book to their kid, you know, the children's books, good night books, because you would read the child to sleep. And for some reason, we, as we developed into adults, we thought, "Well, we no longer benefit from having a story read to us to help us sleep." No, it's not true. We s- we benefit hugely. In fact them, the meditation company, Calm, you know, was saved by the, the introduction of sleep stories into their app. They were doing pretty well as a meditation app, but then they started to do sleep stories and it became a unicorn company, um, in terms of its valuation. It broke a billion dollars, and it was on the f- the back of sleep stories.

    15. SBSteven Bartlett1:21:23

        Mm-hmm.

    16. MWMatthew Walker1:21:23

        And what they realized is that people were self-medicating their insomnia by way of meditation, so they latched onto that and then they found that these stories, sleep stories, were great. And you've got now wonderful people, people who you've interviewed on this show. So what you're doing and what those sleep stories are doing and what meditation is doing, it's all the same thing, which is that it is taking your mind off itself because when you are struggling to sleep or you've woken up in the middle of the night, what you don't want to be doing is focusing on either what you, what you, "What did I do today? What did I not do today? What did I do poorly? Oh my goodness, what have I still got to do tomorrow?" And at that point, things are just a disaster. You're wide awake. What all of the things that we've just discussed do is they take your mind off itself, and at that point then you start to allow sleep to come back naturally. That's why one of the other suggestions is take yourself for a mental walk. So, don't count sheep by the way, that doesn't work. A colleague of mine at UC Berkeley did this that he actually takes you longer to fall asleep if you're counting, uh, sheep. What she found, uh, Dr. Alison Harvey, was that if you just close your eyes and you think about a walk that you take frequently, let's say it's a walk with the dog, and you think about it in high fidelity detail. "So I close my eyes, I go out the door, I take a left down the steps, then I'm going to go up the street. I take the first left past that pine tree." That's the level of detail. If you just walk yourself on that mental walk, sure enough people fall asleep in about 50% less time, half the time it takes.

    17. SBSteven Bartlett1:23:06

        This is the thing with sleep stories and also my serial killer documentaries or serial killer podcasts that I listen to. Detail.

    18. MWMatthew Walker1:23:13

        Exactly.

    19. SBSteven Bartlett1:23:14

        You get... E- even I've listened to Calm's sleep stories before and their attention to detail in their sort of descriptive nature of what they're saying is so apparent. They'll say things like, "The cold wet windowsill saw the raindrops," like, s- um, "tapping against it one by one by one by one." And that sounds very similar to my serial killer documentaries when I hear about the serial killer coming in through the window-

    20. MWMatthew Walker1:23:39

        Yeah. Yeah. Yeah.

    21. SBSteven Bartlett1:23:40

        ... right? (laughs) At nighttime. Um, and I wondered why the descriptive nature of it, the detail matters for dozing us off.

    22. MWMatthew Walker1:23:47

        And because it prevent... I mean, you've got limited bandwidth in terms of cognitive capacity.

    23. SBSteven Bartlett1:23:51

        Right.

    24. MWMatthew Walker1:23:52

        And if you're consumed and you saturate your bandwidth with that level of detail, it's very hard for any of these other things called our worries and our anxieties to start entering into our mind. The other thing I would note, by the way, though is if you are, if none of these things are working for you, if the fictional notion of serial killing is not working for you, if meditation is not working for you, if going on a mental walk is not working for you, this is the final suggestion I have. If you're lying there awake... Firstly, by the way, if you're struggling with sleep, remove all clock faces from your bedroom. It's one of the best pieces of advice I can give you. Knowing what time of night it is is no favor. So knowing now that it's 3:23 AM in the morning and I'm still struggling to fall asleep, and then I look back at the clock and it's now 4:03 AM and I've still been awake, and now it's 4:27 and I've got to wake up at 6:30 AM, knowing that has no utility for you. Remove all clock faces from your bedroom. It is a gift. But coming back to the final suggestion, if you don't want to get out of bed, if you don't want to listen to a podcast, the final thing I would say is just accept and say, "Look, it's okay. Tonight is not my night. It is not the worst thing in the world. And instead of trying to sleep, all I'm going to do here is lie in bed and I'm just going to rest." Because wouldn't it be lovely if someone came to you in the middle of your workday, you're just stressed, and someone said, "By the way, just come into this room. There's a, there's a bed here. Just lie down and just rest for an hour. Wouldn't it be lovely? Just have a good old rest for an, an hour. Just rest there." And I would say that if you can't sleep, just lie in bed, stop worrying about sleep and not being able to get it, stop worrying about the next day. Just lie in there and enjoy a nice good old rest. And by the way, usually what happens is that-... after you start thinking, "Okay, I'm going to rest."

Episode duration: 2:05:40