Understanding the Science of Sleep & Decoding Your Dreams w/ Dr. Matthew Walker EP 1476

0:01Calling all conscious achievers who are seeking more community and connection. I've got an invitation for you. Join me at this year's Summit of Greatness this September 7th through 9th in my hometown of Columbus, Ohio to unleash your true greatness. This is the one time a year that I gather the greatness community together in person for a powerful transformative weekend. People come from all over the world and you can expect to hear from inspiring speakers like Inky Johnson, Jospree Singh, Vanessa Van Edwards, Jen Sincero, and many more. You'll also be able to dance your heart out to live music, get your body moving with group workouts, and connect with others at our evening socials.

0:44So if you're ready to learn, heal, and grow alongside other incredible individuals in the greatness community, then you can learn more at lewishouse.com slash summit 2023. Make sure to grab your ticket, invite your friends, and I'll see you there. Dream sleep provides a form of almost overnight therapy that dream sleep is emotional first aid and it's during dream sleep at night that your brain takes those difficult emotionally charged experiences sometimes even traumatic memories and it welcome to the school of greatness my name is Lewis Howes, a former pro athlete turned lifestyle entrepreneur.

1:27And each week we bring you an inspiring person or message to help you discover how to unlock your inner greatness. Thanks for spending some time with me today. Now let the class begin. Welcome to today's special episode. Over the last 1300 plus episodes, there've been so many impactful interviews that I've been lucky enough to have. And I always like to reflect on some of the most powerful. And this episode was one that resonated with most of you guys in the past, and I'm excited for the value it's going to bring you today as well. So I hope you enjoy today's episode. Welcome back, everyone, to the School of Greatness.

2:06I'm very excited about our guest. Dr. Matthew Walker is in the house. Good to see you, sir. How are you doing? Good to see you, Lewis. Thank you so much for having me on the show. I'm excited about this because as a former athlete, as someone who's always wanted to perform at high levels in business and sports and just have a great life. I've been obsessed with the topic of sleep, and I've been obsessed with creating sleep sanctuaries, figuring out what plants you put in your room when you sleep, what temperature should it be, the blackout shades, all this stuff. I've been obsessed with this. And I'd love to start with asking the question about if we sleep poorly, how does this impact our brain?

2:48if we just sleep poorly one night or over and over and over again? How does that impact the brain chemistry? Yeah. So I think firstly, in response to the general question, sleep is probably the single most effective thing that you can do to reset both your brain, but also your body health, of course, as well. And I don't say that flippantly against the notions of diet and exercise. Of course, both of those are fundamentally critical. But if I were to take you, Lewis, and I were to deprive you of sleep for 24 hours, deprive you of food for 24 hours, or deprive you of even water or exercise for 24 hours, and then I were to map the brain and body impairment that you would suffer after each one of those four, hands down by a country mile, a lack of sleep will implode your brain and body far more significantly.

3:43The only one I would probably lose out on is oxygen. At that point, I'll give it up. You know, sleep will take the silver medal. Oxygen definitely gets the gold. But thereafter, sleep seems to be paramount. Over sleep, food, and water, sleep is the most important thing. I would say, yeah, you know, I used to say that sleep was the third pillar of good health alongside diet and exercise. But I think the evidence has suggested that I was utterly wrong, that sleep, in fact, is the foundation on which those two other things sit. And you can do wonderful things in those two domains, but if you're not getting sufficient sleep, those things tend to be far more futile as a consequence.

4:28And so what is sufficient sleep then? So right now we recommend somewhere between seven to nine hours for the average adult. Once we know that you go below seven hours of sleep, we can start to measure objective impairments in your brain and your body. And in fact, the number of people who can survive on less than six hours of sleep without showing any impairment rounded to a whole number and expressed as a percent of the population is zero. without any impairment what does that mean so if i can measure lots of different operations of your brain let's say your cognition your attention your learning and memory also your moods and your emotions and your anxiety or downstairs in the body i can measure aspects of your cardiovascular system or your blood pressure or i could measure your immune system or your metabolic system how it's regulating your blood sugar and your glucose, I can measure this sort of pinwheel, this kaleidoscope of health metrics on Lewis Howes.

5:32And then I can see when I keep dialing you back with less and less sleep, at what point do I see at least one of those things demonstrating a breaking point? And it's very rare for us to be able to find any individual who can go below six hours of sleep and not show some kind of impairment. And a great, even frightening demonstration of this, a study took a group of perfectly healthy individuals and they limited them to six hours of sleep a night for one week. And then they measured the change in their gene activity profile relative to when those same individuals were getting a full eight hour night of sleep.

6:12And what happened? And there were two critical findings. The first was that a sizable and significant 711 genes were distorted in their activity caused by that one week of short sleep. And that's, you know, in some ways, I think about this, Lewis, because it's reality. We know that almost a third of the population is trying to survive on six hours of sleep or less. So it's not just, you know, total sleep deprivation, which doesn't happen very frequently. It's a common occurrence. What I found most interesting was that about half of those genes were actually increased in their activity, the other half would decrease.

6:49Now those genes that were suppressed were genes associated with your immune system. So you became immune compromised or immune deficient. Those genes that were increased in their activity or what we call overexpressed were genes associated with the promotion of tumors, genes that were associated with cardiovascular disease and stress, and genes that were associated with long-term chronic inflammation within the body. And I make that point just because, you know, many people, I think, have this concern about things such as genetically modified embryos or even genetically modified food. But when we don't get sufficient sleep, we are unwittingly performing a genetic manipulation on ourselves.

7:35You know, if we don't let our kids get the sleep that they need, then we're inflicting a similar genetic engineering experiment on them as well. Wow. This is crazy. So what if you've been sleeping less than six hours a night for years? What is that saying to your genes? And is there a way to recover the gene damage and reverse and go back to a healthy genes, healthy body, healthy life? So firstly, we know that short sleep duration. So using that sweet spot, and we can speak about oversleeping or excess sleep because I think that's an interesting part that hasn't been spoken about too much. But using that recommended CDC amount of seven to nine hours of sleep, there is a simple fact, firstly, across the lifespan, which is the shorter your sleep, the shorter your life.

8:25Really? That short sleep predicts all-cause mortality. But then we can dig a little bit deeper and start to sort of ask, you know, exactly what is going on? Why is there such mortality risk caused by insufficient sleep? and what we know is that a lack of sleep and typically getting certainly less than six hours of sleep is associated with a high risk of cardiovascular disease, high risk of diabetes, high risk of stroke, high risk of dementia and I would love to double click on that and go into the Alzheimer's disease risk because that now evidence is very very strong and then downstairs in the body we know that there is links between a lack of sleep and certain forms of cancer.

9:04after if I were to take you and limit you to let's say four or five hours of sleep for one week your blood sugar levels would be so disrupted that your doctor would classify you as being pre-diabetic oh my goodness so that's not a lifetime that's just one week and there's an even more interesting experiment that I speak I think speaks to the subtlety of this because the there is the largest sleep study that's ever been conducted and it happens actually to around around 1.6 billion people across 70 countries twice a year. And it's called daylight savings time. Now, in the spring, when we lose just one hour of sleep opportunity, firstly, what we've seen is that there seems to be a 24 % increase in relative heart attack risk the next day, which stuns me.

9:55And what's fascinating, in the fall, in the autumn, when we gain an hour of sleep, there's a 21 % reduction in heart attacks. So it's bi-directional and that's just one hour of sleep. And you see, there was some great recent data. You see a very similar profile regarding that daylight savings shift for road traffic accidents on our streets. I've heard about this. Tragically, suicide rates as well. And then even more recently, what we discovered is that during that spring time shift when you lose an hour of sleep, the sentencing of federal judges is significantly harsher because their mood and their emotion is that much worse because of that one hour of lost sleep that they dole out harsher sentences.

10:44So, you know, we can walk, you know, you can ask the question, what about a lifetime? We don't even have to ask about a lifetime of short sleep. We can ask about these really, you know, one week of short sleep or even one night of one hour of lost sleep. And I think that's how fragile our brains and our bodies are to this thing called a lack of sleep. And you could then ask, well, you know, why are we so sensitive? Because I can go without food for 24 hours and I can go without water for 24 hours, you know, I'm still not too bad. I'm in fairly decent shape. Why is sleep the exception to that rule?

11:23And the answer seems to be this. Human beings are the only species that will deliberately deprive themselves of sleep for no apparent good reason. Why is that? And it was such a unique thing. And what that means is that mother nature through the course of evolution, because no other species does this without real need for survival. And I can speak about some of the exceptions, but human beings are strange like this. In other words, Mother Nature hasn't had to face the challenge of coming up with a solution called sleep deprivation because she's never faced it in the course of evolution. And so there is no safety net in place here.

12:04And that's why we think human beings implode so quickly and thoroughly, mentally, cognitively, and physically, caused by insufficient sleep. And why do you think, why is the, why are the majority of people bad at getting good sleep? Is it, what is it? We're distracted. Is it, we think we need to be doing more as we're stressed and worried about the past and the future. Is it, you know, what we just want to work harder. What is the main cause of why we get poor sleep? That's, it's such a fundamental question. And in some ways it's all of the above plus. So I think the first, and I've thought about this a great deal, why are we suffering this global sleep loss epidemic that we're under right now?

12:48I think the first thing is that, unfortunately, sleep has an image problem. That, you know, the PR agent for sleep should be fired. Because we associate sufficient sleep with this concept of being lazy, of being slothful. And that's a terrible disservice to this thing called sleep. and it is very different to things like diet and exercise. You know, I think a lot of people like to virtue signal with, you know, what they eat, and they certainly are very proud to tell you, you know, I work out five times a week, I'm in the gym at this time of morning, and, you know, all of which I think are great, and to be applauded and supported, but we have the very opposite.

13:31We have this almost, you know, well, we, we don't. some niches of society have this sleep machismo attitude. You know, this kind of, you can sleep when you're dead mentality, which by the way, based on the evidence is mortally unwise. Yeah. It will lead to both a shorter life and a life that is significantly less healthy. So I think the first thing is we need to change our cultural appreciation of sleep from something that is a waste of time to something that in fact is an incredible investment. It is probably the very best and the most freely available democratic and painless health insurance policy that I could ever imagine.

14:16I think the next thing is the way that we work in society. We are working for longer hours and before the pandemic people were commuting increasingly longer amounts of time. What that meant was that people were leaving the house earlier, they were arriving home later, and no one wants to shortchange time with family or Netflix or whatever is your poison. And so the one thing that has become squeezed like vice grips in the middle of the night is this thing called a sufficient bout of slumber. but then there are plenty of people who give themselves the opportunity to get enough sleep but they can't obtain it and that is where things such as insomnia or sleep disorders things like snoring come into play and you touch on and I know that you've spoken and I'm so grateful for what you've done regarding discussions of mental health we know that one of the principal roadblocks to getting this thing called a good night of sleep is anxiety.

15:21Stress, worry, anxiety, regret, all those things. Resentment, holding on to all that stuff. That is toxic to sleep. You're absolutely right. And in fact, anxiety and physiological stress is our principal model for the explanation of insomnia right now. It's not the only cause, but it seems to be one of the principal causes. and in modern society it's become so easy and I'm not finger wagging I you know I'm just as guilty we are constantly on reception but rarely do we do reflection and unfortunately the time when most of us do reflection is when we turn off the light and our head hits the pillow and that's the last time oh you know because I don't know about you Lewis but you know at night in the dark thoughts are not the same thing.

16:16You know, concerns become twice as big or the 10x the size of concerns. I start to worry, I ruminate, I catastrophize. Yet in the light of day, those things seem very different. And so we can speak about sleep tips perhaps later on, but certainly getting right with your emotions and your anxiety is key to good sleep. And that's one of the things that prevents sleep. I also think that there is an issue at the public health level. You know, we've had in many first world nations, wonderful government mandates regarding health, regarding drink driving, regarding, you know, safe sex, regarding drugs and alcohol and even food and even inactivity and sitting.

17:04And when was the last time you heard of a first world nation provide a public health message and memorandum regarding sleep? Never. And I don't remember one either. So from every level at, you know, at a public health global, you know, government level down to a workplace level, you know, we lord the airport warrior who's flown through four different time zones in the past three days. They were on email at two and then they're back in the office at six, you know, we, so So we need to... We celebrated those people. We did, you know. And the funny thing, by the way, is that after about 20 hours of being awake straight, you are as cognitively impaired as you would be if you were legally drunk.

17:52Now, I would never, you know, as a CEO say, I have got this fantastic team of people. They're drunk all of the time. But we do say, I've got this fantastic group of people. They just are at it all hours. They are dedicated. They're always working. You know, they spend minimal time sleeping. They're just all out. They love this project. But we've got this strange mentality. And then I think it comes down to, you know, even within schools, we've got this incessant model of early school start times. And super early, isn't it? It's, it's incredible. We got to be there, what, 6.30 or 7 or something, right?

18:316.30, 7, 7.30. And that data is actually very powerful. What we found is that when we delay school start times, first academic grades increase, truancy rates decrease, psychological and psychiatric issues decrease. But then what we also discovered is that the life expectancy of students increased. And you may be thinking, well, hang on a sec, you know, how do you measure that? And the leading cause of death in teenagers 16 to 18 is actually not suicide. That's second. It's road traffic accidents. And here sleep matters enormously. And I'll give you one example. It was in Teton County in Wyoming.

19:18They delayed their school start times from 7.30 in the morning to 8.55. By the way, what are we doing trying to educate our children at 7.30 in the morning? No, I can't think. Yeah, I mean, I remember being in school and being every day was hard for me. Every day I was tired. Every day I was hard to focus or I'd be irritable or wanted to like, you know, jittery or something. But it was like so hard to focus. And then you're at lunchtime and then I eat and I'm tired again afterwards. And you want me to focus and pay attention at a desk. It's like that doesn't work like that for me, especially on no sleep.

19:53Well, for any sort of developing brain, it doesn't work like that. And for some people, to make a 7.30 a.m. start time, school buses will begin leaving at 6 o 'clock or 5.30 in the morning. That means that some kids are having to wake up at 5, 5.15. This is lunacy. And what we've understood from the academic grades, and I'll come back to the car accidents in a second, when sleep is abundant, minds flourish. And when it's not, they don't. And what we've discovered with the road traffic accidents in Tenton County, when they made that shift, the only thing more remarkable than the extra one hour of sleep that those kids reported getting was the reduction in car crashes.

20:41The following year, there was a 70 % drop in vehicle accidents. And to put that in context, you know, the advent of ABS technology, anti-lock brake systems, that dropped accident rates by 20 to 25 percent and it was deemed a revolution. Here is the simple fact of getting enough sleep that will drop accident rates by 70 percent. So, you know, I need to get off my soapbox. But what I would say is this. I think if our goal as educators 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.

21:22Is anyone listening to this that you've been speaking about this too, and they're actually adopting this new model, whether it be work time or school time or just integrating this? Do you no systems that are integrating this? There have been some. And I think I've tried to do this in the education domain. I've tried to do this within medicine because the way that we train residents is almost inhumane. Actually, it's not almost. It absolutely is inhumane. And the statistics there are stunning as well. And then I've tried to do it in the workplace too because I do a lot of speaking events at sort of Fortune 500 companies.

22:00And at first, I think I took the wrong approach where I was really speaking a little bit more about sort of the compassionate approach, you know, why it's good and kind for people to gift them more sleep. Because I see sleep as a biological necessity. And if it's a biological necessity, then I think it's a civil necessity. And if it's a civil necessity, sleep is a civil right. But what I would say is that that wasn't particularly well received. You know, I'd go into business companies and say, your employees, you know, they're desperate for more sleep, they will be happier and healthier. Or I would speak about medicine and I would speak about, you know, what it was doing to the patients and the harm.

22:47And it would fall on deaf ears. What I then realized is that if you're going to change large organizations, you have to speak in their currency, which is money. And then I would describe the medical malpractice lawsuits that would commonly cost savings within medicine, firstly. And then administration started to change the tune. Because before that, you know, there was almost this old boys network in medicine where we went through residency, and it's almost a hazing. And despite armed with incredible data to the contrary, I think the mentality 10 years ago when I started trying to do that was my mind's made up, don't confuse me with the evidence.

23:31Crazy. Why? It's because they went through that themselves and so they want to pay it back or something. I think so. I think there was some of that. I went through hell, so everyone else has to go through hell. Yeah. Right. It's a rite of passage. You know, if you are tough enough, you'll make it through. It's kind of like boot camp, which I don't think we need to do anymore. And then within business, you could describe, you know, the RAND Corporation did an independent survey a couple of years ago. And what they found was that insufficient sleep will cost most nations about 2 % of their GDP of their gross domestic product.

24:04So here in the US, that number was$411 billion of lost productivity due to insufficient sleep. In Japan, it was $130 billion. My home country, the UK, it was over$50 billion. So if I could solve the sleep loss crisis within the workplace, I could almost double the budget for education in the US, or I could halve the healthcare deficit. So when you speak about money, then people start to listen. So that's how I've tried to communicate. And I don't think I'm a particularly good communicator, and I've been sometimes bull in a china shop, as I probably have been for the first, however long we've been talking.

24:46But it's just because I'm so, you know, I'm just desperately passionate about this thing called sleep. And some years ago before I started trying to, I wrote a book and then I've been doing podcasts. Sleep was the neglected stepsister in the health conversation of today. It was a second citizen. And I was so sad to see the disease, the sickness, the harm the lack of productivity the impact on education that a lack of sleep was having and i think i just came out probably a little too strong you know it was sort of sleep or else dot dot yeah i'm curious oh go ahead yeah no no sorry please i'm curious what is the has there been research or studies done on if someone who has a horrible diet they eat horrible They smoke.

25:35They drink occasionally. But they get eight hours of sleep versus someone who gets five hours of sleep but works out hard every day, eats perfect, clean, vegan, whatever the perfect, clean diet is for them. Don't smoke. Don't drink. I wonder who has more susceptibility to diseases and cancers and poor health and which problems are each case more prone to have. Perfect eating, but not proper half the amount of sleep, four or five hours a night, but you're taking care of physically, you're taking care of spiritually and nutrition versus you sleep perfect. maybe you won't be able to sleep perfect if you're eating that bad but you sleep eight hours a night nine hours a night but you're eating horrible who has it worse off so firstly i think you should be a sleep scientist because it's a fantastic good study it's a great study and it's an incredibly complex but important study to do the first answer is that no one has actually done that type of experiment.

26:45We've done a diluted version, a kind of, you know, diet version, a light L-I-T version of it, which is we look at sleep and we ask, what is it in terms of the mortality risk and the health consequence risk when you're not getting sufficient sleep? And then we take all of those other factors that you've described, smoking history, diet history, mental health history, et cetera, et cetera, and we add those as additional factors into the analysis and we absorb them and control for them so that we can say independent of those things or in spite or in the face of those things, sleep still carries a significant vote in determining your mortality, your rate, your date of expiration, as it were.

27:33So that's the only evidence that we have right now where you can at least control for those. but we haven't done what you're describing, which is the much more elegant, smart thing to do, which is, you know, can we put them sort of almost in a Coke, Pepsi, Dr. Challenge, kind of Dr. Pepper challenge phase and see which one wins out. You know, diet, exercise, or sleep when those two other things are held constant, but you manipulate one of those, then hold the other two constant and manipulate one of, lovely experiment, love to do it, but it's not being done. So we don't know. What would your hypothesis be?

28:09My suspicion is that sleep will still probably carry a larger influence than those two other factors. Now, there's a lot of assumptions I'm making there, but I'll give you another quick example. A study done back in the 1980s, which will probably never be repeated because of the moral and ethical issues, they took a group of rats, and what they found after sleep depriving the rats was that rats will die as quickly from sleep deprivation as they will from food deprivation. So sleep is that essential. Those rats were dying usually within 20 days. So sleep seems to have a deathly consequence to it.

28:50What was also fascinating, however, is that they then, and maybe I'll back up a little bit, human beings and most mammalian species will have two main types of sleep, what we call non-rapid eye movement sleep or non-REM sleep and rapid eye movement sleep or dream sleep. And what they found was that total sleep deprivation will absolutely kill a rat. If you just selectively deprive the rat of either deep non-REM sleep or REM sleep or dream sleep, they found that the rats would still die of either one of those two. So both of those types of sleep are essential. But rats were dying almost as quickly from dream sleep deprivation as they would from total deprivation.

29:35Well, they died within about 40 days, whilst the rats who were deprived of deep non-rem sleep, they died after about 60 days. So, you know, we can almost then, not that I would wish to, pit the different types of sleep head to head and ask, which is more important. Now, I should say all stages of sleep are critical. That's probably one of the biggest messages that we've learned. Different types of sleep do different things for your brain and your body at different times of night. All of them are important. But it seems as though if you want to ask the question of death risk, dream sleep may be more important than deep sleep on the consequence basis of how quickly you die, but you need all of them.