Sleep Expert Matthew Walker: Do THIS to Sleep Through The Night And Never Wake Up Tired Again

2 Jun 2025 · 1 h 34 min

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Podcast Episode Summary: Sleep Expert Matthew Walker

Podcast Title: On Purpose with Jay Shetty Episode Title: Sleep Expert Matthew Walker: Do THIS to Sleep Through The Night And Never Wake Up Tired Again

Episode Overview In this episode, Jay Shetty interviews Dr. Matthew Walker, a renowned neuroscientist and sleep expert, to discuss the critical role of sleep in health and well-being. Dr. Walker, author of *Why We Sleep*, provides insights into the science of sleep, debunks common myths, and offers practical strategies for improving sleep quality.

Key Themes and Concepts

The Importance of Sleep

  • Sleep significantly influences various aspects of health, including emotional processing, hormonal regulation, and memory consolidation.
  • Dr. Walker introduces the QQRT framework:
  • Quantity: Recommended sleep duration is 7-9 hours for adults.
  • Quality: Importance of uninterrupted sleep; fragmented sleep is detrimental.
  • Regularity: Going to bed and waking up at the same time each day.
  • Timing: Aligning sleep with biological rhythms; awareness of individual chronotypes (morning vs. evening types).

Myths About Sleep

  • The Eight-Hour Rule: Dr. Walker challenges the notion that everyone needs exactly eight hours of sleep, emphasizing individual variability.
  • Sleep Apnea: Approximately 80% of people with sleep apnea are undiagnosed. It significantly affects sleep quality and overall health.
  • Caffeine and Alcohol: Both substances disrupt sleep. Caffeine should be avoided 10-12 hours before bedtime; alcohol negatively fragments sleep cycles.

Strategies for Better Sleep

  • Assess Sleep Quality: Use apps like Snore Lab to track sleep patterns and potential issues like sleep apnea.
  • Create a Sleep-Friendly Environment: Reduce light exposure in the evening and maintain a quiet sleep area.
  • Implement a Bedtime Routine: Engage in relaxing activities an hour before sleep to signal the body it's time to wind down.
  • Avoid Clock-Watching: Remove clocks from the bedroom to reduce anxiety about waking up.

Practical Takeaways

  • Sleep Hygiene: Create regular sleep habits and an optimal sleep environment.
  • Diet and Sleep: Eat light, healthy meals in the evening and avoid heavy or spicy foods close to bedtime.
  • Mental Health Connection: Poor sleep can lead to emotional instability and heightened anxiety.

General Insights

  • Dr. Walker emphasizes that sleep is not a luxury but an essential investment in health, impacting everything from physical health to emotional well-being.
  • He cites studies linking sleep deprivation to increased susceptibility to chronic diseases and reduced overall life quality.

Closing Thoughts

  • Jay Shetty encourages listeners to take actionable steps to improve their sleep, reiterating the profound implications of sleep on daily life and mental health.
  • Dr. Walker’s insights aim to foster a deeper understanding of sleep’s vital role and motivate individuals to prioritize it.

Resources Mentioned

  • *Why We Sleep* by Matthew Walker
  • Snore Lab App
  • MEQ (Morningness-Eveningness Questionnaire) for assessing chronotypes

Final Notes This episode serves as a wake-up call regarding the importance of sleep, equipping listeners with the knowledge to instill better sleeping habits for enhanced overall health and quality of life.

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Transcript

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0:00This is an iHeart Podcast.

0:31Maybe you need to do more than wait. Any business can use AI. IBM helps you use AI to change how you do business. Let's create smarter business, IBM.

0:50She's seen Encanto more times than she can count. And she can count to 10. She mentioned Mirabel in every conversation. but the moment she actually met Mirabel, she was speechless. That's pura magia. Find yours at Walt Disney World Resort. Five years, 10 months, and two days. That's how long it took to grow the 38 inches to ride on Cali River Rapids. But the moment the wait finally ended, that was pura magia. Discover it at Walt Disney World Resort. Hey everyone, it's Jay Shetty and I'm thrilled to announce my podcast tour. For the first time ever, you can experience On Purpose in person. Join me in a city near you for meaningful, insightful conversations with surprise guests.

1:36It could be a celebrity, top wellness expert, or a CEO or business leader. We'll dive into experiences designed to experience growth, spark learning, and build real connections. I can't wait to meet you. there are a limited number of vip experiences for a private q a intimate meditation and a meet and greet with photos tickets are on sale now head to jsheddy.me forward slash tour and get yours today right now we estimate that approximately 80 percent of people who have sleep apnea are undiagnosed that's crazy please welcome matt walker what is good sleep and should we just use the metric of quantity.

2:20The range is somewhere between seven to nine hours. Once you start to get less, the shorter your sleep, the shorter your life. When sleep is abundant, all of a sudden, your appetite hormones are rebalanced. So you naturally stop eating as much as you wanted to. The weight starts to come off you and you're simply sleeping the weight off yourself. It sounds like you're saying that sleep is that number one domino that then naturally helps all of the others. If you are not sleeping in harmony with your natural biological sort of rhythm, then your sleep quantity and quality is worse. Regularity may be as if not more important than quantity.

3:01And I would say to anyone listening, if you're going to do anything with this podcast, just do this one thing. The number one health and wellness podcast. Jay Shetty. Jay Shetty. The one, the only Jay Shetty. Hey everyone, welcome back to On Purpose, the place you come to become happier, healthier, and more healed, three of the most important priorities in our lives. Today's guest is someone that I've been wanting to speak to for a long, long time about a subject that I believe is critical to our health, happiness, and healing. Today I get to speak to Matthew Walker, a sleep expert scientist, author, podcast host, and professor of neuroscience at UC Berkeley.

3:46Translated in 40 different languages, his bestselling book, Why We Sleep, explores the goal to reunite humanity with sleep. Matthew's work has shaped public understanding of how a simple thing like sleep impacts memory, aging, and disease prevention. Please welcome to On Purpose, Matthew Walker. Matt, it's great to have you here. Jay, an absolute pleasure to be here. Thank you so much for having me and giving me the opportunity to speak the voice of sleep. So thank you. I love it. I love it. Matthew, let's dive straight in because there's so much to decipher with you. And I want to start off by asking you, how much sleep do we actually need?

4:28Yeah, it's an interesting question. And there is definitely a range. I think there is, and perhaps even populated by idiots like me, that there was this magical eight-hour number that was you know, necessary and get anything less and there's doom and gloom. The range is somewhere between seven to nine hours for the average adult. And what we certainly know is that once you start to get less than seven hours of sleep, we can measure impairment in both your brain performance, as well as your body metrics. So there is a range, but in some ways, it's also a question of what is good sleep? And should we just use the metric of quantity?

5:07And we absolutely should, because using that sweet spot of seven to nine hours, it looks as though the shorter your sleep, the shorter your life. Short sleep predicts all cause mortality. So duration, total amount, is necessary. But if you actually look at the science, what is good sleep can be really answered by a four-part equation that, in my mind, there are really sort of four macros of good sleep, three macros of food, fat, protein, carbohydrate, for sleep, four macros. And you can remember it by the acronym QQRT. And it stands for quantity, quality, regularity, and timing. So quantity, you're absolutely right.

5:48Somewhere between seven to nine is that fit. Quality is about the continuity of your sleep. Is your sleep fragmented and littered with all of these awakenings? and you're awake for a lot of the night, that's not good quality of sleep. So you could be in bed for nine and a half hours and still get seven hours of sleep, but you're spending two and a half hours of time awake. That's not good quality of sleep. Then we can speak about regularity, going to bed at the same time, waking up at the same time. It sounds very benign. Well, do I really have to worry about regularity? There's a great study and they looked at regularity in quantity.

6:27Both of them predicted all-cause mortality. So if you're very regular and you get that seven to nine hours of sleep, you have the lowest mortality risk. But then, because they had these two measures in the same individuals, they put them in the same statistical analysis and did the sort of Coke-Pepsi challenge between the two. What they found is that regularity beat out quantity in terms of predicting your mortality, meaning regularity may be as, if not more important than quantity. Now you've got to get both, but so QQR, quantity, quality, regularity, timing, timing sounds like regularity. And you think, well, what's the difference?

7:08Timing is about your chronotype. Are you a morning type, evening type, or a neutral? And it turns out by the way, that if you're a night owl, it's not your fault. It is genetically or largely genetically determined. there are at least 22 different genes that dictate whether you want to be a morning person or an evening person. So you don't get the choice. It's gifted to you at birth. And what we find is that if you are not sleeping in harmony with your natural biological sort of rhythm, then your sleep quantity and quality is worse. So let's just say we take someone who goes to bed at 10pm and wakes up at 6am.

7:47Well, if you're a slight morning type, that's actually quite ideal for you. But if you're an evening type who likes to go to bed at 2am and maybe wake up at 10am, then it's the same eight hour window that they're getting. But if the night owl, 2am to 10am, is forced to sleep from 10pm to 6am, still eight hours, the quality of their sleep that they get will never be as sufficient as the morning type. So some people will come to our sleep center and say, I have terrible sleep onset insomnia. I get into bed and I'm awake for the first two hours and then I fall asleep. And we do a chronotype assessment, which is morning type, evening type.

8:31And by the way, people can do this online very quickly right now. You can just type into Google MEQ test, MEQ. It stands for morningness, eveningness questionnaire. And it fits very well with your genetics, takes about three minutes. When we do this type of assessment with them, what we realize is that they don't have insomnia. They're a night owl, but they're trying to sleep like a morning type. And so when you sleep sort of against your natural biological predilection, your sleep is not going to be as good as it could be if you moved yourself closer to your natural innate biological tendency.

9:12Does that make some sense? So those to me would be, yeah. Yeah. Can you shift your sleep time? If people want to, if someone said, Matt, that makes so much sense. I've been a night on my whole life, but I just feel like I should be trying to sleep early and wake up early. It would be better for my partner. It would be better for my lifestyle, better for my kids, whatever it is. Can you shift your type? It's a really good question. I get asked that a lot because in some ways, what I'm talking about is the ideal world. And drum roll, none of us live in the ideal world. We live in this thing called the real world.

9:48So, you know, stop your fancy sleep science and tell me just, you know, can that change? There was a study done by a group in Australia, and they took, I think it was about 11 different things that you had to do as a night owl to see if they could drag you back so you felt more capable of going to sleep earlier. and it was things like as soon as you wake up, eat a large breakfast, go and get daylight first thing, exercise before midday, do not nap, take an earlier lunch, don't nap again in the afternoon, in the afternoon start to get as much darkness as you can, meaning put shades on if you're going to go outside, in the evening make sure that you eat at least three hours before you expect to go to bed and then try to push your sort of alarm clock the next morning by about one to two hours.

10:39And they collected all of these different sort of regiments. And sure enough, they were able to drag people back by a little bit over one hour, which sounds great. But the problem is these were extreme night owls who would prefer to go to sleep at maybe, let's say 1.30 a.m. That means they're still having to go to bed biologically at 12.30 a.m. It's not the 9.30 p.m. or the 10 p.m. that you would prefer. And imagine trying to capitulate and adhere to that regimen for the rest of your life. So there is some wiggle room, it seems, that you can sort of manipulate. But in truth, I think what we have to try and do as best we can is to say, how can I align myself better with my biology?

11:25When you fight biology, you normally lose. and the way you know you've lost is disease and sickness. And that's what we see with night owls who are sort of trying to sleep against their tendency. That said though, is there a way that you can, I mean, hack isn't the right word, but there are ways that you can try to help yourself. So think about what you do in the morning that takes time. So is it that you sort of, you know, make the coffee, you put the coffee in the coffee pot, you get your clothes ready for work, you pack your bag for the gym after work. All of these things you can do ahead of time the night before to take that 15 minutes of added time the next morning and say, allow yourself to sleep a little bit later.

12:09So you're at least getting closer to your natural tendency. Then go to the front end of sleep and say, what is it that I do in the last 15 minutes before I go to bed? Well, I usually sort of, maybe I take a shower, maybe I change for bed. Maybe, you know, I brush my teeth. Maybe some people take their makeup off, whatever it is, set an alarm two hours before bed, do all of those things. And then right before you go to bed, when that alarm goes off the to bed alarm, all you do is get up and you go straight to bed. So you've saved yourself 15 minutes on the front end. So you can go to bed 15 minutes sort of later, and you can wake up 15 minutes later, but you're not necessarily having to go to work any later.

12:53So does that make some sense? So you can try to short sort of thin slice some of that a little bit. Yeah, absolutely. If you're someone who's waking up tired regularly, like right now someone's listening and they're just like, Jay and Matt, I wake up every day and I'm just tired. Yeah. And I'm trying to get the right amount of sleep but I'm still figuring it out. Where do I start? What would you encourage them to look at? So I think the first thing, let's go back to the four principles. are you getting a consistent seven to nine hours of time, at least in bed? Next, are you trying to assess your sleep and say, am I waking up a lot throughout the night?

13:30I would say that's one of the first places I would go to. Yeah, let's focus on that. Yeah, if you're not feeling restored and refreshed by your sleep the next day, and you're getting four hours of sleep a night, then it's obvious. It's just not the right quantity. But if you're being good, and you're spending sufficient time in bed, but still feeling unrefreshed and restored, we have to ask, are you waking up a lot throughout the night? If you are, let's figure out why. Is it that you are, for example, snoring a lot throughout the night and you have undiagnosed sleep apnea? And you can just download an app on your phone.

14:04I have no association with them. It's called Snore Lab. So Snore, L-A-B. And you download it, it records your breathing. You place the phone next to you on your bed. Then in the morning, it shows you a Richter shock sort of scale throughout the night. And it quantifies your snoring into quiet, moderate, loud, and epic. And the frightening thing is you can then tap anywhere throughout the night and you can hear yourself snoring in a way that we don't. So next thing is let's make sure that you don't have an undiagnosed sleep disorder. Then I would say, is it a case that you're maybe over consuming on caffeine during the day?

14:43Some people will feel completely comfortable having an espresso with dinner and they say, I fall asleep and I stay asleep. So I'm one of those, and it is genetically determined who can metabolize caffeine quickly and it has no effect. We've done studies. And unfortunately, even if you do fall asleep and stay asleep, that caffeine can prevent you from going into the deepest stages of what we called deep non-repid eye movement sleep. That's where you get a lot of restoration sensation from. So maybe we need to ask how much caffeine are you taking? The dose and the timing make the poison. Try to cut yourself off after about three cups and try to stay away from caffeine at least 10 to 12 hours before you expect to go to bed.

15:24The final thing I would probably say is, are you also using anything in the evening to help you fall asleep? And the principal thing I'm talking about here is alcohol. It's probably the most misunderstood sleep aid that there is out there. It's actually not a sleep aid and it will fragment your sleep and block you from getting rapid eye movement sleep. So what we would do is we would march you through a set of environment or behavioral things. What are you doing in terms of your bed timing? Are you spending a lot of time awake? And also the things that you're taking into your body, alcohol, caffeine, etc.

16:00The final thing I would say is stress and anxiety. If there is one outside of skeletal pain, the principal reason that we as a society seem not to be sleeping is this Rolodex of anxiety. Because, and you've spoken so eloquently about this, in this modern era, we are constantly on reception. Very rarely do we do reflection. And the only time now in the modern world, when we do reflection is when our head hits the pillow. And that's the last time that we need to do reflection because at that point, the Rolodex of anxiety starts whirring. At that point, you start to ruminate. When we ruminate, we catastrophize.

16:42And then everything feels twice as bad in the dark of night than it does in the light of day. And at that point, we're dead in the water for the next two hours. So the final thing I would say is let's speak about your mental state. So does that give you a sense of the pinwheel diagnostics that we would go through? I absolutely love it. I love it. I love the acronym. I love how simple and formulaic it is for us to be able to actually measure what's going wrong. And I can, I'm fortunate and very grateful and knock on wood, sleep very, very well and generally always have. But whenever I have had disturbances in my sleep, I can easily pinpoint it to something you've said.

17:23And that shows me how great the model is because as someone who is lucky and fortunate enough to have great sleep, when I have been disrupted, it's always been related either to caffeine, to stress and anxiety. I can easily draw the parallels because it's such a rare occurrence. And so I can see why and when. I want to dive into each of those. Let's start with sleep apnea because I think that's something a lot of us don't actually know enough about. And so I love the fact that people can use the app SnorLab, as you mentioned. How many people are actually struggling with sleep apnea, don't even know about it?

17:56And what is actually happening if you have sleep apnea? Yeah, two great questions. So right now we estimate that approximately 80 % of people who have sleep apnea are undiagnosed. That's crazy. which if you look at the numbers is going to be a non-trivial proportion of the population. And the reason it's so dangerous is because when you have sleep apnea, essentially what's happening is that your airway is either partially becoming obstructed or like a straw, it's collapsing flat entirely. Now, if it starts to become obstructed, so let's say you're sleeping on your back and the airway flaps in that airway are starting to give way to gravity, then you'll start to get a partial blocking, a partial what we call occlusion of the airway.

18:45And that's what you hear when you hear the sound. That's the sort of the flapping of the partial occlusion. And then when you stop breathing entirely, at that point, the airway has completely collapsed. The straw has gone flat. And after about 15 or 20 seconds, your brainstem registers the alarming buildup of carbon dioxide in your blood, because at that point you are slowly asphyxiating and it sends a wake up trigger up to your cortex. And then all of a sudden you hear and you gasp and you're awake. So imagine now we have a way that we measure these sort of occlusions and these partial collapses.

19:27And it's called the AHI score. Don't worry about it. It but the apnea hypopnea index. Suffice it to say that we look to see how many events like this are you having per hour of sleep. And if you were to have very mild sleep apnea, you may be having 5, 10, 15 of these events. That's considered mild. Some people could have 80 of them per hour. But let's just say you have mild sleep apnea, 10 of these events an hour, and you're in bed for eight hours. So imagine the following scenario with undiagnosed mild sleep apnea. What if I were to say tonight, I'm going to come into your bedroom, Jay, and every hour I'm going to throttle you, strangle you to the point where you actually stop breathing.

20:10And I'm going to do that 10 times every hour for every one of the eight hours. So I'm going to do that 80 times throughout the night. Do you think you're going to feel restored and refreshed by your sleep the next morning? And the answer is no, but that's what, now that's hyperbolic, of course, but in some ways that's what we're facing even with the mildest version of undiagnosed sleep apnea. That's why sleep apnea, untreated, is associated with a very significant increase in all-cause mortality, as well as increases in mortality related to diabetes, to cardiovascular disease, as well as certain forms of cancer.

20:46So I think for me, it's the case of it's not only going to erode the quantity of your life, meaning your lifespan, it will certainly shorten your health span. That's what most of us are worried about. Not really our lifespan, it's our health span. None of us want to live with disease or sickness. I certainly don't want to. And I remember there was a patient that we work with, with sleep apnea. And after they were treated, they were saying, well, before that, I just thought this was me at 57 years old. I just thought I would deteriorate it with age. And I realized there was someone in there that wasn't the way I felt.

21:23And when you treated me with sleep apnea, it was almost as though someone cognitively had wiped a fogged glass clear and finally I could see again. And so that's why I think so many people can benefit by way of just simply doing, taking this app, seeing whether you snore. Also, you can do something called the stop bang questionnaire. So S T O P all in caps dash B A N G. And you can do it also online. And it's a very quick questionnaire, probably about two minutes, and it will evaluate your risk likelihood of having sleep apnea. One of those two, if you fear that you have sleep apnea, or if you know that your partner has sleep apnea, please go and get it seen to it's a laughing matter.

22:13You know, we think, well they they sound like a chainsaw they wake the neighbors up it's almost this thing of sort of humor yeah trust me when it comes to your health and your wellness it is anything but a funny story when it comes to undiagnosed sleep apnea yeah thank you so much for giving such practical tips as to how we can check as well and i hope everyone who's listening and watching please go do that because the fact that 80 percent of people may not have a clue and that could be the secret behind better sleep is crazy to me that we haven't uncovered it for 80 % of people. That's huge. And so many downstream consequences happen when they get treated, that they are typically overweight.

22:53They usually have high levels of blood sugar, of blood glucose. They typically have hypertension, high blood pressure. And what's nice is that when you were to say, okay, we've got to have you reducing your food intake. We need to stop you from eating sugar. We need to get you to the gym, all of those things have Herculean in their challenge. And people often in that state of being overweight, hypertensive, high glycemic, they just find it so hard to change. But if you treat them with sleep apnea, when sleep is abundant in good quantity and quality, which it will be when you treat them, all of a sudden your appetite hormones are rebalanced.

23:33So you naturally stop eating as much as you wanted to. The weight starts to come off you and you're simply sleeping the weight off yourself. It's a largely painless equation. You don't crave those sugary, sort of high sugar, sort of immediate hit foods. So your blood sugar comes back into control and you're more motivated to be physically active, meaning that your cardiovascular health. So I sometimes think of sleep, You know, if you've seen one of those fancy music studios where they've got all of the dials on the mixing deck and you can move any one of them. But sleep to me is that one dial all the way at the far left that if you move it, all of those other dials just kind of move up.

24:16It's the tide that floats all of our other health boats. And so if you get that one straight, so many things as a manifold, like an Archimedes lever, will consequently change downstream for the better. You don't even have to do anything. You just have to start sleeping better. Let's take a short break to hear from our sponsors. Parking shouldn't slow you down. ParkWiz gives every driver a shortcut. Book ahead, save up to 50 % and skip the hassle of circling the block. Park smarter, park faster. ParkWiz. Download the ParkWiz app today and save every time you park. This week on a very special episode of Health Discovered, We're taking a closer look at a condition that affects hundreds of thousands of men each year, prostate cancer.

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25:44Five years, 10 months, and two days. That's how long it took to grow the 38 inches to ride on Cali River Rapids. But the moment the wait finally ended, that was Puida Magia. Discover it at Walt Disney World Resort. And let's get back to our episode. It sounds like you're saying that sleep is that number one domino that then naturally helps all of the others. And I've had everything that you just said. I, for the past six weeks, I've been in LA, which is rare in terms of I haven't traveled, I haven't jumped on a plane. I've been in one place. and because of that I've been able to really dial in on everything from sleep working out eating right because I've had no reason to have an error because I've been at home yeah and you know when you travel you maybe whatever right you you eat something that wasn't great it's hard you're in a hotel room whatever it may be I've been here for six weeks I've been on a phenomenal schedule last week I I was only gone for like four hours away I took a three-hour flight took a three-hour flight back.

26:44I was gone for like four to six hours in total. And I landed back at 4am, which is rare for me. I don't do that. I usually sleep by 9.30pm. I'm a morning person for sure. And I got back at 4am. I tried to get some sleep. I probably got up at 8am because that's all I could sleep at that time. I got in a workout, but I had to tell my trainer to lower my level of workout because I was more tired than I've felt for a long time. And I actually felt weaker. so I've been feeling really strong across the last six weeks but I felt weaker I was like I don't think I can lift that much today I'm not feeling up to it on top of that all my sugar cravings went through the roof that day isn't it interesting yeah and you notice it so significantly when you're at the other end where you're like oh wait I haven't needed refined sugar for like weeks on end now but this one day all I'm craving is fats and sugars and that's all I'm after and I did give in and I was okay about it But it's so interesting to feel it that abruptly and that extremely.

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27:45And you're so right. I wanted the sugars. I wanted the fats. I wanted, I couldn't work out as well. All of it makes a difference. And in some ways, what's great now is the science is compelling in terms of the mechanism such that firstly, there are two appetite regulating hormones. They're called leptin and ghrelin. Now, leptin is an appetite hormone that when it's released, it says, okay, you're satisfied with your food, you don't want to eat more. You're satiated. Ghrelin is the opposite. It says you're not satisfied. You're still hungry. You need to eat more. And what we find is that when we start to sort of thin slice people's sleep, and it doesn't take very much, you can sort of get maybe six hours of sleep for five nights or five hours of sleep for four nights.

28:31All of a sudden, the hormone leptin, which says you're satisfied, you're good, you don't need to eat anymore, that starts to decrease. At what point? Well, it usually takes about four nights of somewhere between four to five hours of sleep reduction to already see those changes and see appetite behavior changes as a consequence. So it doesn't take very much. And then if that wasn't bad enough, ghrelin, the hormone that says, oh, no, no, no, you're still hungry. Please, please eat more. That goes up. So in some ways, it's double jeopardy that you're getting punished twice for the same crime of insufficient sleep.

29:08Once by switching off the signal of I'm full, I don't need to eat. And once again, by I'm hungry and I need to eat more. Then what we have also found is that we have inside of us what we call endocannabinoids. So people have heard of sort of cannabis, the way that most people have heard about it is an exogenous sort of intake of cannabis. But we have naturally occurring cannabinoids in our system called endocannabinoids. Now, many people will, let's say, know someone, of course, I'm not going to judge anyone, will know someone who've said, when I, you know, when I smoke weed, I get the munchies, I get hungry.

29:47That seems to be one of the consequences of these cannabinoids. Now, endocannabinoids inside of us also do the same thing. They can make us more hungry. When you are underslept, you're naturally occurring cannabinoids, these endocannabinoids, they also increase. And that drives you to eat even more in addition to the changes in leptin and ghrelin. And then finally, we did a study with brain imaging, where we scanned people's brains with and without good sleep, looking at different food items from highly desirable to highly healthy. When you are underslept, the rational control regions of your brain in the frontal cortex, they get shut down.

30:26And these more hedonic, deep emotional brain centers that respond to rewarding, pleasurable foods, they started to become much more reactive. And it set you on this path of almost obesogenic eating, where you crave those sort of, you know, the sugars, the chocolates, the stodgy carbohydrates, and you don't go towards the leafy greens and the healthy nuts. You go after the pizza and sort of the salty snacks. So all of which is to say you get this sort of conspiring both within the body and also at the level of the brain that explains exactly what you were just describing as a sort of a phenomenon.

31:03And that's why I think this, you've always got to be careful with epidemiological studies where you say, okay, shorter sleep equals higher body mass index, higher chances of obesity. There could be many things, but when you experimentally manipulate sleep and you can unpack the mechanism, then we can entertain causality. For sure. So what's the, you said earlier, we should be eating three hours before we go to bed. What's the ideal meal type three hours before we go to bed? A, so that we don't get hungry just before we go to bed. And B, because I also understand that the digestive process can actually make sleeping much harder.

31:43And so what should we be trying to digest in those three hours that keeps us full and doesn't disrupt our sleep? Yeah, it's a really good question. And And so there, the sort of the three hours, what we were trying to do is take those night owls and try to drag them back in time. But if you're not a night owl trying to sort of manipulate your sort of sleep timing, we can then just ask for anyone who's just, you know, in their standard sleep regimen, when should you cut yourself off? And it's actually a bit of a myth because there is this strong sentiment out there on social media, you need to stop eating maybe three or four hours before bed.

32:18If you look at the data, and I did this sort of analysis of all the literature, if you eat as close as 60 minutes before bed, it doesn't seem to hurt your sleep. Now, if you sort of go 45 minutes or 30 minutes, then yes, it does seem to have an impact blast radius on your sleep. Nevertheless, that's a very different question than saying, what would be beneficial to my sleep? I'm phrasing the question as, at what point does it become harmful for your sleep? And the answer is you can eat up to an hour before bed and show no harm on your sleep. But that's very different than saying, but what if you'd stopped eating two hours or two and a half hours, would that have actually improved your sleep?

33:01I think what we're seeing in the data is that it's very idiosyncratic, that you need to test drive it and you will know which kind of quote unquote type you are. Some people, mostly night owls, have a preference to eat late in the day or early in the evening and very little in the morning. Whereas morning types like to eat sort of breakfast like a king, lunch like a prince, and dinner like a pauper. You know, they scale down. I think it's dependent on your chronotype. That said though, the two ways that food can disrupt us, first, if we're eating high sugar content foods at night, it has a disruptive impact.

33:41And we know this in part because it could be the, not just the activating level of sort of alertness in the brain that happens with a sugar hit. It's also that simple sugars are what we call thermogenic, meaning that when we take on board sugar, it can just very gently increase our core body temperature quite quickly. And it turns out temperature is key for sleep. We need to drop our brain and our body temperature by about one degree Celsius or about two to three degrees Fahrenheit to fall asleep and stay asleep. And it's the reason you will always find it easier to fall asleep in a room that's too cold than too hot.

34:21The room that's too cold, it's taking you in the right direction for good sleep at night. So when you onboard simple sugars at night, it starts to just moderately, just gently increase your core body temperature, which can disrupt your sleep. So I would say content, try to aim for, if you're going to go after sort of carbohydrate, make sure that they're complex carbohydrates that release their energy in a much slower fashion. Also try to aim for a protein based, you know, yogurt is fantastic at that point. Make sure it's not, you know, highly sweetened yogurt because then you're taking on board sugar, unfortunately.

34:59So yogurt together with some kind of slow release carbohydrate is probably a fantastic approach to food. The second way though, that you can disrupt yourself above and beyond the macros of food is that when you eat too late, particularly spicy food, it can cause acid reflux. And that reflux is one of the other reasons that eating too close to bed will disrupt the quality of your sleep. So try to go after more of a slow release sort of protein, maybe a casein based protein, and then aim for, if you're going to go after carbohydrate, just make it a smaller portion and make it a complex carbohydrate.

35:36That's probably the best recommendation. Yeah, no, it's so important to hear about all the versions of it because I do think sometimes when you hear, oh yeah, you can eat up until the last hour, you'll be fine. It's so different to, well, how do I get into performing at my best and feeling at my best? And when you're already struggling with the quality of sleep, every minute kind of factor is going to make a difference. That's right, yeah. And it's just, yeah, I'm really happy that you've gone into the detail there of like, you know, why is it that we're saying three hours or what does that look like?

36:11As I was hearing you speak, I was just thinking about just how hard it's become for people to regulate their lives and manage this. I know in some cultures, it's just so natural to eat really late before you go to bed. How much does eating a late meal also push back your time of wanting to go to sleep, or is there no correlation there? No, there actually is a correlation. It's a very astute observation, actually, which is you can have one type of biological chronotype predilection, but you can almost violate that biology and override some of it by creating certain conditions under which it will distort your natural rhythm.

36:58One way that this rhythm is played out is the release of something called melatonin. And melatonin is a naturally occurring hormone. And it simply tells your brain and your body when it is darkness, when it is night, which is to say melatonin helps with the timing of our sleep. And there are ways that you can artificially delay your natural melatonin release. A good one would be being exposed to too much light in the evening, too much artificial light, what I would think of as junk light. You know, there was this concept a while back of junk DNA. Well, I think there is something called junk light and we get too much of it at night because we are a dog deprived society in this modern era.

37:38But there's other ways that you can delay your natural biology. And if let's say that all food was taken away, all electric light was gone, all internet service was down and, you know, the lights were out, you would naturally say to me, well, I'm someone who would probably not get sleepy until midnight. And then all of a sudden, as I said, no food, electromagnetic pulse takes out all electricity, everything is gone. All of a sudden you probably say, gosh, it's 10, 15 PM. I actually feel quite sleepy. And it's because modernity through all of its changes, light, social media, you know, sort of entertainment that we're constantly exposed to, it's dislocated us from our natural sensation of biology telling us it's time to sleep.

38:27Most of us think that, well, I'm probably, you know, a midnight to 8am type person. When if I took you camping in the Sierras for two weeks, and we had all of our sort of fancy technology measuring your sleep-wake rhythms, and we would actually find, you know, you're much closer to a 1020 to 630am kind of person. But modern sort of industrial life has come in the way of that. And it is modified our perception. So to come back to your elegant insight, there are ways that we can almost contort our natural biology, one of which is things like social media, electric light. But another one is that you can just manipulate things like food timing.

39:13And that food timing will create an activating alertness sensation in the brain and the body and force you perhaps to go to bed or feel tired and two hours later than you naturally would otherwise. So you have, the way that we usually measure someone's natural sort of tendencies is we bring them into the laboratory and we say, say goodbye to your friends and your family for the next week. We take all daylight away, no windows, no nothing. And we just measure your natural biology when we separate you from everything that is in the outside world. And that That way we can bring you back to your innate tendencies.

39:50And usually there is quite the mismatch between when we interview you and say, what is your natural rhythm versus when we measure you, what is your biological rhythm? Those two things are often quite different. Yeah. Thank you so much. As you were talking, you mentioned melatonin. And I was thinking about obviously the rise in melatonin gummies, melatonin supplements, I guess you could take before going to bed. And then you also have sleeping pills. Walk us through what's in sleeping pills versus melatonin, gummies, or the sort, and what's your take on both? Yeah, it's very interesting. And obviously just being a scientist rather than a medical doctor, what I could offer you is sort of scientifically descriptive advice rather than necessarily medically prescriptive advice.

40:34But melatonin has had this meteoric rise in the sleep supplement world. And now here, at least in America, where it's not regulated by the FDA, you can go into a supermarket or a grocery store and down the sort of the health food section, there is this big sort of purple sector and that is the melatonin sector. Melatonin, it can be useful to help regulate your circadian rhythm. And so I will use it strategically if I'm traveling. If let's say I go back home to the United Kingdom and I live just outside of San Francisco, it's eight hours ahead. So I can use it to try to trick my brain into thinking, oh, it's nighttime on the first night I arrive in the UK, when in fact, my melatonin peak is not going to arrive for at least another eight hours because I'm still back on California time.

41:26So, but for the most part, the way people use melatonin is night after night after night. And if you look at the studies, melatonin will only increase the speed with which you fall asleep by about 2.2 minutes. And it will only increase the efficiency of your sleep by about 3.7%, which isn't that much more above and beyond placebo. And the reason is because melatonin doesn't participate in the generation of sleep. Melatonin is a little bit like the starting official at the 100 meter race. It brings all of the great sleep races to the line and begins the great sleep race, but it doesn't participate in that sleep race.

42:06That's a whole different set of brain chemicals, which we'll come on to with sleeping pills. So that's the reason that melatonin isn't a particularly effective sleep aid. It's the reason that you will never see people being prescribed melatonin for insomnia for the most part, unless they have some kind of circadian rhythm disorder. So I would say if you're using melatonin for the purposes of improving the speed with which you fall asleep or the generation of sleep, it may be a placebo effect. And by the way, the placebo effect is the most reliable effect in all pharmacology. So maybe no harm, no foul.

42:41The only other caveats I would offer with melatonin, first, because it's not regulated here by the FDA, you don't know the purity. And there was a great study that's been replicated and they looked at, I think it was about 20 different vendors of melatonin. And they sampled what was inside of the pill. Based on what they said on the bottle versus what was actually in the pill, it ranged from about 80 % less than what it said to 460 % more than what it stated on the label. So it's a bit of a wild west. You don't quite know what you're getting when you take this. Yeah. So you've got to, I would say, be a little bit careful.

43:20For the most part, melatonin is largely in a compound anyway, so we don't need to get sort of, you know, too phosphorylated about it. What's your take on the fact that when we're taking these, I guess artificial supplements of melatonin that it depletes our body's ability to make it and regulate it at the right times that we actually need it? Yeah, and that's another critical question and that's one of the fears that we have. I think the data we don't have right now to say one way or the other, but if you think about let's say a male who's undergoing hormone replacement therapy with exogenous testosterone, what we know is with certain forms of testosterone replacement therapy, after some period of time, the testes will stop producing their own testosterone.

44:06And even if you were to stop your exogenous injection of testosterone, your production of testosterone innately never returns. And the worry is, is that the case with melatonin? Now, there have been a number of case studies that have looked at melatonin use, let's say for up to four or even six weeks of constant use. And when they stop, melatonin production returns. So it looks as though we don't have to worry. My worry though, with those data, when someone has sort of offered them to me is to say, but most people in society, they're not using melatonin like that. They've been using it for years, not six weeks.

44:45So I think I'm still a little bit sort of concerned. The other thing, or two other things, one is that the dose that people typically take is what we call a supra physiological dose, meaning it's far higher than anything your body would naturally release. So people are taking five milligrams, 10 milligrams, maybe sometimes even 20 milligrams. Whereas what we would recommend in sleep medicine is somewhere around about one, maybe maximum of three milligrams. So, you know, log orders of magnitude higher. The other thing too, to keep in mind is that melatonin now is being more and more used in the pediatric setting.

45:23So you'll see these melatonin gummies for kids. And there was some data, gosh, now probably 30 years ago, looking at juvenile male rats, meaning that they're going through that sort of adolescent phase, and they were getting dosed with high amounts of melatonin. And that high dosing of melatonin in the juvenile male rats actually stunted their sexual development. So it stunted testicular growth and it caused testicular atrophy, meaning shrinking of the testes. Imagine if I were to go to, let's say, a teacher and parent meeting one evening at a school and get up there and say, I would like you this evening to start dosing your children with a bioactive hormone.

46:06And it is a hormone that I would like you to dose your children with every night at maybe five to 10 times the natural release. and also it's a hormone that may actually disrupt their sexual maturation and development. Who's with me? You know, and at that point people would, you know, boo you off the stage, rightly so. Now, again, I'm being hyperbolic and we don't know if there is that concern or not. I'm simply saying that if we don't know, my sort of suspicion, at least personally, would be I'd probably err on the side of caution, at least at this stage, particularly because the FDA recently released data demonstrating that admissions to hospitals for melatonin overdose have increased by 503 % in the past 10 years.

46:54So there is something going on with melatonin, I think that we need to be mindful of. Again, though, it's largely an inert compound. So I don't mean to be scaremongering here. Your second part of the question was sleeping pills. And it's a really interesting evolution. I think we're now at the stage of sleeping pills 3.0. We sort of web 1.0, 2.0, 3.0. It's kind of the same with sleeping pills. We started off with the classic benzodiazepines, things like Valium. And they work to go after an inhibitory chemical in the brain, neurotransmitter in the brain, called GABA, which stands for gamma-aminobutyric acid.

47:34Don't worry about the name. It's simply the red light stop sign for brain activity. These things like Valium, they would go after this GABA system in the brain, and they would activate it and essentially just knock out your cortex. And then the second generation of sleeping pills came along, the Ambien, Linesta, Sonatas of this world. They also go after that GABA inhibitory neurotransmitter system in the brain, but they just sort of tickle the receptor in the brain a little bit differently. but for the most part, they are doing the same thing. And that's why we call them the sedative hypnotics because they are sedating your cortex.

48:14Now, if you take an Ambien at full dose, I'm not going to argue that you're awake. You're clearly not awake, but to argue that you're in naturalistic sleep in some ways is an equal fallacy because if I show you the electrical signature of your sleep with and without Ambien, they're not the same. And in some ways, Ambien will come in and it will take a bite out of the deepest of the deep, slow brainwaves of deep non-REM sleep, sort of this big dent that you see that happens. And so again, it's not necessarily to say that there isn't a time and a place for the use of those medications. Sleep medicine right now does recognize them as being useful potentially in the short term to start to begin treatment for insomnia, but they are no longer the first line recommended treatment.

49:06And one of the reasons that in a book that I wrote where I was sort of, I probably wasn't overly enthusiastic about those Web 2.0 sleeping pills, the Ambien's, Lenosis, and Sinatis. And it was for several reasons. First, because sedation is not sleep. And when you take those medications, you mistake the former for the latter, but it's not natural sleep. We also know that those sleeping pills have been associated with higher risks of mortality in certain forms of cancer. Now, those associations, we don't know necessarily that that's causal. But then there was another very interesting study where they looked at how sleep helps your learning and your memory.

49:45And one of the incredible things about sleep is that it will take recently learned memories and that memory circuit in the brain, sleep, will strengthen the synapses so that you come back the next day. And that memory is almost, it's like hitting the save button on those memories. You cement it into the architecture of the brain. And they did a study where they dosed animals after learning a maze or different types of learning, and they could measure the strength of the memory circuit. And then they gave them natural sleep. And sure enough, the next day, sleep had almost doubled the strength of the memory.

50:20Then they did a version where they dose the animals with a body appropriate amount of Ambien. And those animals slept longer. And you would think, well, if sleep is helping the memories and strengthening that memory circuit, sleeping longer should lead to an even greater strengthening of the memory. Unfortunately, Ambien had unwired the memory and it had actually reduced the strength of the memory by 50 % 5-0. So to me, that's just a demonstration that perhaps the quality of sleep is not a naturalistic quality of sleep. And it may not therefore be transacting the natural functions that sleep typically provides like learning and memory.

51:01There is a newer class of medications though out on the market. And I think the evidence right now is still early, but so far, I actually think that they look really quite effective. And again, I think people had taken my stance to be, I'm very anti-pharmacology in general. I'm not. I'm very pro-pharmacology if the pharmacology is good and not necessarily causing you harm. And these new class of medications, they are called the Dora's drugs. And it's D-O-R-A small s. It's a class of drugs. And there are currently three FDA approved. Probably the first one was called Bell Somra. It's a play on sort of beautiful sleep.

51:45and the actual chemical name is suvorexant. These medications do something really much more elegant. The ambience and the lunastasis has said that's just a sedative hit to the cortex. These new class of medications, the Doras, they go after a wake promoting chemical called orexin. You can think of orexin like the wakefulness volume button. And when it's turned up, we're wide awake. And these medications, they come in and they act like an additional set of chemical fingers. And they just go after the volume button of wakefulness of orexin and they just dial it down. And then they step back and they allow the antithesis of wakefulness to come in its place, which is this thing called naturalistic sleep.

52:28And so I think right now I'm probably more bullish on those medications. Again, a lot of water to pass under the bridge before we understand them. But so far, I think that they're a much more elegant and nuanced way of manipulating sleep. The other thing I would be remiss to mention is there is an alternative to these medications in general, and it's called cognitive behavioral therapy for insomnia or CBTI for short. It is just as effective as sleeping pills in the short term. But what's nice is that when you stop working with your therapist after maybe six or eight sessions, not only do you with a sleeping pill like Ambien, when you stop, you typically go back to the bad sleep that you are having, or you actually have rebound insomnia where your sleep is even worse.

53:14But with a therapist, they're giving you the tools and techniques. It's sort of the difference between, let's say, giving a woman or a man a fish versus teaching them how to fish. This way, you actually understand how to manipulate your sleep. They give you the tools and then you can continue to sleep better for years later, even after you've stopped utilizing the therapy, unlike medications. So I would just say that that's a little bit about both melatonin, the sort of the emergence of these new flavors of sleep medications, and then an alternative should people wish for that. Yeah. It's so worrying because I think we've got so used to treating our brain and our mind like technology and this desire to just switch it on and off, power up, power down, power on, power off.

54:01It's almost like you don't ever really stop to think what's happening in order for that to happen. And I know I didn't for a long time where I grew up and you just pop a, well, paracetamol from where we're from, but Advil from, you know, in the US and you've got a headache, just take this, it's gone. You know, you can't sleep, take this, you fall asleep. And you're not really recognizing what's happening at a chemical level and how many consequences there are and what's actually happening beneath the scenes. And I think it's so easy to forget because it's giving you the instant thing that you want in that moment.

54:36But the kind of circuitry that it's kicking off or closing down has far more long-term consequences that, like you said, we're not even aware of. It's sad and hard and difficult that wanting to get these natural things to happen that we are naturally wired to do, right? These chemicals are being naturally produced and there are natural things we can do to boost those chemicals within ourselves that will hopefully get us to go to sleep. As you talked about, like seeing light first thing in the morning, like, you know, being outdoor more, reducing blue light in the evening, reducing exposure to junk light, as you called it in the evening.

55:15I've definitely seen that one make a big difference. I'm someone who generally loves light. I really like being in bright places. And my wife's the opposite. she knows she's very much like wants to follow the sun. And so when it's dark, she'll be like, all the lights have to be off in the house. And recently when we've been watching our shows, we've been watching our shows in total darkness, apart from the screen, obviously. And it's so natural for both of us to just feel tired earlier. And we'll be like, all right, time to go to bed. And we don't have our screen in our bedroom. And so we'll finish watching whatever we're watching.

55:48And we've, sometimes we'll both even like, you can tell we're just falling asleep while watching. We figure it out, turn it off and go to our bed and we're out to sleep. And just simply completely making it dark in the evening has had a huge, huge impact on me. Honestly, I love that you bring this up. And I would say to anyone listening, if you're going to do anything with this podcast in terms of an actionable event, just do this one thing. For the next week, if you get the opportunity, just do me this favor. set a to-bed alarm one hour before you would normally go to bed. And when that alarm goes off, shut down 50%, if not 75 % of all of the lights in your home.

56:31And then see how soporific that will make you feel, how sleepy that will make you feel. It's really quite striking. And then don't just stop there. Do what I would call the off-on-off version of the experiment. So baseline, you're coming in, you're normally leaving the lights on blazing. Now we go into the on version of the experiment, the intervention, which is darkness one hour before bed. And then after that one week, go back to doing what you used to do. Keep all of the lights blazing for right up until you go to bed. And don't just ask the question, did my sleep get any better when I did the manipulation of one hour before bed, switch the lights off?

57:15Ask the question, did my sleep go back to being actually worse when I returned to keeping the lights on? And so you show bi-directionality. And when you show bi-directionality, it's usually a much more powerful version of the experiment. And if honestly you can say to me, it made no difference to my sensation of feeling drowsy and sleepy or the quality of my sleep, then no problem at all. Keep doing what you're doing. And it just didn't work for you. That's fine too. But first, here's a quick word from the brands that support the show. Parking shouldn't slow you down. ParkWiz gives every driver a shortcut.

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58:36Anything with cancer, you just think death sentence. And the only thing I could think about was, who's going to take care of my family? You have to go out there and build your support system. You got to build your team. In this episode, we'll explore the science behind detection, along with the practical steps men can take to protect their health. Listen to Health Discovered on America's number one podcast network, iHeart. Open your free iHeart app, search Health Discovered, and start listening.

59:37She's seen Encanto more times than she can count. resort. All right. Thank you to our sponsors. Now let's dive back in. I love what the advice you gave for people who are struggling with insomnia. For someone who's waking up, they go to sleep for three hours, but then they're up. They finally put themselves back to sleep after an hour and a half and they sleep for maybe another three hours and then they're back up again. For that person, what's the most helpful way for them to be able to fall back asleep in that moment? So we've talked about the roots of the issues and the core from the acronym.

1:00:08But what about that person who's just like, I just want to know how to get back to sleep for another three, four hours if I could. What's the quickest way I can do that? I would say there are three things to keep in mind here. When I often hear that description, people will say, I always wake up at, it's about 3.15 in the morning or it's 4.10 and it just happens so reliably. My first question to them is, how do you know it's four o 'clock in the morning? That's your problem. you're looking at the clock and knowing that it's 3 15 or 4 a.m. in the morning does you no favors at all it's not going to change the outcome so the first recommendation is remove all clock faces from the bedroom it's okay to if you really must do keep your phone next to your bed but keep it out of sight even though i would strongly recommend that you keep your phone in the kitchen or even better still a friend of mine recommended recently just put it in the garage put it in your car in the garage.

1:01:03And that way it's the amount of motivation effort to go and get your phone within the first 10 minutes of the morning is very, very high, meaning you're probably not going to do it. So let's baby steps. Let's just say crawl, walk, run. First thing to do, just make sure you can't see any clock faces. And if you wake up, resist the urge, because as soon as you start doing that night after night, you're actually training your brain, reinforcing it to wake up at 3.15 in the morning. So we've started that. The next question is, well, what should you do about it? You know, don't tell me the fancy, remove the clock, help me.

1:01:38At that point at night, either if you've woken up or you just can't fall asleep, it works for both of these. The problem here is that you have to get your mind off itself. Because at that moment, when you're awake, you start thinking, okay, I'm awake. This is now going to just obliterate my day tomorrow. I've got that important meeting. I'm now going to be underslept. At that point, the anxiety starts to begin. Then you start thinking, oh gosh, I remember now I didn't do that one thing that I should have done for tomorrow morning. And then I've got to do that thing for next week. And I also didn't do that thing last week for, and again, at that point, that's going to keep you awake for the next one or two hours.

1:02:21So your job to try to get back asleep is to disengage the mind. How do you do that? I would say there are probably four or five different tools that you can use. The first is meditation. It may be or may not be for you, but if you look at the data, meditation for sleep, immensely powerful. If meditation is not your thing, just do something simple like breath work, and you can just Google box breathing and anything like that is great. You could also just do a simple body scan, start at the top of the head, move down, just, and again, Google body scan, and you can start to train yourself to do that.

1:02:57The next thing you could do is listen to a sleep story or just listen to a podcast. Make sure it's on a timed sort of shut off. But again, all of these things, common across all of them, is you're getting your mind off itself. If I'm meditating, I'm not thinking about my worries. If I'm breathing, I'm focusing on the breath. If I'm doing some kind of a relaxation, a body scan again, I'm just moving through my body. It's very hard for me to think about my anxieties. If I'm listening to a sleep story, I'm engaging in sort of the externality of the story, not my own internal worries. And then the final thing that was done, is a great study done at UC Berkeley, not by my group.

1:03:37They found that taking yourself on a mental walk in hyper detail was wonderful. So let's say it's a walk that I take with my dog and you've got to remember it in high detail. So I think, okay, I open the drawer, which colored leash am I going to take? I'll take the blue one, clip it in with my right hand, with my left hand, I open the door, take a left down the stairs, go up. It's at that level of detail. And all of these things are taking your mind off itself because at that time of night, sleep is a little bit like trying to remember someone's name. Sleep is not something that you make happen.

1:04:12Sleep is something that happens to you. And like trying to remember someone's name, the harder you try, the further you push it away. And it's only when you stop trying, does it return to you. Absolutely. And that's the same way with sleep. And normally, if you engage in some of these methods and tools, the next thing that you remember is your alarm going off in the morning. Why? Because you took your mind off itself. Totally. If that doesn't work, and you are consistently waking up and spending long amounts of time in bed awake, then we may have to implement one of the methods in cognitive behavioral therapy for insomnia, which is something called bedtime restructuring.

1:04:54It used to be called sleep restriction therapy. And for reasons, obviously you can think it's not the best name where you come to me and say, look, I'm having real problems getting enough sleep. My say, great, we're going to do sleep restriction therapy. And you say, no, no, wait a second. You didn't hear me. I can't get enough sleep. And you're saying you're going to restrict my sleep. It's actually not sleep restriction. It's time in bed restriction. So you tell me, okay, I am in bed for eight hours and I'm awake for two hours across the night. So I'm only getting six hours of sleep, but I'm in bed for eight hours.

1:05:28To me as a sleep scientist, I then know we've got to constrain the time with which you are giving your brain the opportunity to sleep because your brain has become inefficient. It's like saying, I go to the gym and I take an hour to work out. But if you were to actually observe me, I'm actually only working out for about 25 minutes because, you know, at the end, I finished my, you know, my last rep. Then I do the 11th rep, which is I pick up my phone and I start checking social media and then I'm talking to people and utterly inefficient. but then at some point someone says to me, look, today you've only got a maximum of 30 minutes in the gym.

1:06:04And as soon as your 30 minutes is up, we kick you out. The first couple of days, I'm still doing what I normally do. And I get through maybe 15 % of my workout because I'm not doing it efficiently. After a week of doing that, I now realize as soon as I go into the gym, I put my phone down and I just go at it real hard. And I still get my 25 minutes of workout in the 30 minutes. It's the same with sleep restriction. You tell me, okay, I'm in bed for eight hours and I only get about sort of six hours of sleep. Well, now I'm going to say, I'm going to limit you and I'm going to take one hour of sleep away from you.

1:06:40You wake up at the same time, but I want you to go to bed consistently one hour later, maybe even one and a half hours later. You tell me I go to bed normally at 10 p.m. I say, you are now not allowed to get into bed until 1130 p.m. Push through. I don't care. And then you've got to wake up at the same time. And after about three or four days of this, your brain starts to build up. Now, the first couple of nights, you're still going to be sleeping bad. But then after a couple of nights, your brain starts to build up this starvation, this hunger for sleep. It creates a sleep debt. And then after a while, it's like resetting the Wi-Fi button on your router, the brain thinks, gosh, I don't have the luxury of eight and a half hours of time in bed.

1:07:22I'm only allowed six and a half now or seven. And now all of a sudden it becomes incredibly efficient. You stop waking up in the middle of the night. If you do wake up, you fall back asleep very quickly and you end up getting maybe six and three quarter hours of sleep within seven. Whereas you used to get six and a half hours of sleep with eight and a half hours of time in bed. So it's a quite convoluted method, but I would say I would use that as the last approach. Firstly, try to get your mind off itself. If it's still not working, think about sleep restriction therapy. You can just Google it.

1:07:57It's pretty simple. Great advice. Thank you so much. I love how tactical and practical you are. It's so helpful. If there's anyone who's listening to this episode right now and you have a friend or a family member who's struggling with sleep, please pass this episode on because I've never heard someone make it that granular as you are. Honestly, it's so brilliant. And it's so helpful because it's so easy to get philosophical about these ideas. And we all understand how important sleep is and how much we need it. And, you know, I can hear everyone going, yeah, but what do I do? And you're really, you've created a map for people.

1:08:33So thank you so much. Well, I think I was very guilty of doing this. You know, when I first came out a couple of years ago, speaking about sleep, I was speaking all about the science of sleep and the bad things that happen about sleep. And I think someone even said my Ted talk, which I think was called, they name it sleep as your superpower or something should have really been called sleep or else dot, dot, dot, you know, and it did people with insomnia no favors. I understand that now, but I think what I've tried to do is people have said, okay, I get it. Sleep is important, but how, how do I get it?

1:09:05And I completely suffered what we call in neurology is hemi neglect. one half of what I needed to do as a sort of a public intellectual regarding sleep was missing, which is I was telling everyone how critical it was and the bad things that happen when you don't get it. But I wasn't being very helpful because I wasn't telling anyone how it works and how, you know, where is the user manual for sleep? And that's what I'm now trying to do. So thank you for saying that. I'm trying to do a little bit better. Trying to do less bad. Let's just say Yeah. No, it's coming across. Great. I want to move on to talk about caffeine and coffee.

1:09:40You spoke earlier, you said we should be having our last cup of coffee or caffeine at 10 to 12 hours before we go to bed. And when I was listening to that, I was like, I think a lot of people are not doing that. Like from what, at least from the conversations I'm having, I think people are having it much closer to bed or they're having so much that it's affecting their bed. If you had to tell people just a couple of things about caffeine or coffee and sleep, what would you want them to know? I think I would say that firstly, caffeine has a half-life for the average adult of five to six hours, which means that after about five to six hours, 50 % of the caffeine is still circulating in your brain.

1:10:22That means that caffeine has a quarter life of 10 to 12 hours. So if you have a cup of coffee at noon, 25 % of that, a quarter of that cup of coffee is still in your brain at midnight. So I don't think many of us would get into bed and sort of pour a quarter of a cup of coffee and then swig it and then, you know, put your head on the pillow. We understand that that probably doesn't lead to good sleep, but in some ways that's not dissimilar to what you're doing. If you have a cup of coffee at noon, keep in mind, however, there is variability that some people have a faster capability to metabolize or at least clear caffeine from the system.

1:11:00And you can do these genetic tests. And there's an enzyme called the CYP1A2 gene. And that will dictate the speed of it as sort of a liver enzyme, a cytochrome enzyme that will speed or slow down. And you will know if you're caffeine sensitive or not. So firstly, the timing of caffeine can be important. Also the dose. And that's why we've looked at people, even if you just have one weekly sort of drip brewed cup of coffee in the evening, let's say it's just a hundred milligrams of caffeine, it will not necessarily prevent you from falling asleep as efficiently, but it will increase the chances with which you wake up.

1:11:44And if you wake up, it will increase the duration with which it takes you to fall back asleep. And if it doesn't do that, it can also reduce down the depth of your deep sleep. And we know, for example, that it's during that deep sleep when your brain has a cleansing system that washes away things like the Alzheimer's proteins, amyloid and tau protein. So you really would prefer not to try to degrade the quality of your deep sleep, considering all that it does for your brain and your body. But in some ways, that's what many of us are inadvertently doing if we have caffeine too late in the day. I would say though that I've probably changed my tune a little bit on coffee.

1:12:25I would say drink coffee, but the dose and the timing make the poison. Try to, as I said, cut yourself off after about three cups of coffee and try to, you know, cut yourself off at least 10 hours, you know, as a rule of thumb before bed. The reason I reverted back in some ways to say coffee is not necessarily a bad thing to drink. If you look at the relationship between drinking coffee and the health benefits, they are non-negotiably astronomically impressive. Drinking coffee seems to be a very good thing. Now, again, it's dose dependent. Once you get past about four cups of coffee, then it goes in the opposite direction.

1:13:06It's not a good thing. And if you look at that list, and it is quite a list of health benefits and disease de-risking that drinking coffee provides, and you compare that to all of the health benefits that sleep provides, it's a remarkable overlap. So people were saying to me, how do you square that circle? Because that doesn't make any sense. Well, if you look at the data, the reason that drinking coffee is so beneficial is because the coffee bean itself contains a whopping dose of antioxidants. And because in the Western world, we're so deficient in our dietary intake of antioxidants, this one thing, the coffee bean, has been asked to carry the Herculean weight of all of our antioxidant needs.

1:13:53And therefore, that's why drinking coffee has such a health predictive signal in the literature. Case in point, if you look at decaffeinated coffee, has almost the same health benefits. So it's not the caffeine, it's the antioxidants in the coffee bean itself. So again, with all of these things, with alcohol and caffeine, I am just a scientist. I have no right to tell anyone how to live their life. And I don't want to be the healthiest person in the graveyard either. Life is to be lived for goodness sake, live a little bit. All I simply want to do is empower you with the scientific evidence. And then you can make an informed choice as to how you want to live your life.

1:14:37But does that help a little bit in terms of navigating caffeine? Yeah, absolutely, huge. And the other thing you mentioned at this point of the acronym is alcohol. And you were talking about how just the negative effects of alcohol in terms of that disruption of our sleep. If there were a couple of things you wanted people to know about alcohol and sleep, what would they be? Yeah, there I think I probably haven't. changed my tune and I don't see any upside in terms of alcohol for health or certainly for sleep. Alcohol is probably the most misunderstood sleep aid that there is out there. Unfortunately, it's not an aid at all.

1:15:17Alcohol will hurt your sleep in at least one of three different ways. The first thing is that alcohol is also in the class of drugs that we call the sedatives. And again, when you have a couple of sort of nightcaps in the evening, you say, it helps me fall asleep. Alcohol is simply helping you lose consciousness more quickly. It's not really putting you into natural sleep. The second thing is that alcohol will fragment your sleep in the first half of the night. And the reason that it does that is that alcohol will activate the fight or flight branch of the nervous system. Now, in the first half of the night, that's when we get most of our deep sleep.

1:15:57And when we go into deep sleep, we shift from the fight or flight branch of the nervous system over to what we call the parasympathetic nervous system, which is this quiescent nervous branch. Now, alcohol will crank you back over to the fight or flight sympathetic nervous system, which then makes your sleep, the depth of your sleep, far more shallow. So you don't get as much deep sleep. You wake up more frequently, but those awakenings are so brief that you never commit them to memory. So you never think alcohol is harming my sleep by fragmenting it and sort of littering it with all of these awakenings.

1:16:33So your deep sleep suffers, your sleep is fragmented. And then finally, alcohol is very potent at blocking your dream sleep or your rapid eye movement sleep. And dream sleep is critical for things like emotional and mental health. It's essential for creativity. It's also important for hormonal health. It's during REM sleep when we release our peak levels of testosterone in both men and women. And alcohol will sort of shortchange you of that REM sleep. So on all of those counts, you know, I just can't say in good conscience, even a glass of wine with dinner, you know, is that okay? We can see the blast radius.

1:17:12It is in some ways, both a dose and also time dependent process such that if you have, let's say a glass of wine with lunch versus a glass of wine with dinner, the glass of wine with lunch will have less of a damaging impact on your sleep at night. So the completely politically incorrect thing that I would never say on a podcast would be go to the pub in the morning and that way the alcohol is out your system in the evening and no harm, no foul. But no, of course I would never suggest something like that. But yeah, what are you doing tomorrow morning? No, I'm kidding. Before we dive into the next moment, let's hear from our sponsors.

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1:19:10And back to our episode. Like you said, I think it's so easy for human, just ideas that become prevalent in human society that we just take as being normal or habits and practices that become normalized over a certain period of time. And we just start operating like it's normal, it's okay, it's accepted and not really realizing what's going on. And I'm also of the spirit of we should enjoy life and appreciate life and everything else. But I think to really appreciate life, it means to know what works for you and what doesn't and what helps you and what doesn't. And to really recognize the value of the impact of that.

1:19:52Because I think it's really easy to be like, oh, yeah, well, you know, let's just see how things go. And then all of a sudden you hear about a family member or a friend who gets a diagnosis. And then that's when it kind of really hits you. And I've had that far too often where I've had friends and family members at young ages diagnosed with things. and it's consistent with a habit. And by the way, sometimes someone gets something and it's got nothing to do with their habits and it's bad luck and it's everything else. And both of those are positions to be compassionate and empathetic. But I think when it comes to ourselves, I look at it and go, I would like it to not be my own fault.

1:20:28If it happens from something beyond me, great. But if I can avoid it by taking responsibility and accountability for my health, then that's probably a good play and a good way to live. Yeah, I like the way that you're thinking there in the sense that so many of us see sleep as a cost to our lives. Yes. And instead, I think what we have to realize is think of sleep like an investment in tomorrow, not a cost of what I get for today. Yeah. And you're right when you look at, you know, some of the mentality of, you know, I'll sleep when I'm dead. I mean, firstly, what we know from the data is that if we adopt that mentality, you will be both dead sooner.

1:21:08and the quality of your life will be significantly worse as a consequence. But also, if you look at the data between short sleep and cardiovascular disease, if you look at short sleep and certain forms of cancer, not all forms of cancer, short sleep and dementia risk, imagine if you were to say in 20 years time when you're at the hospital and you've just lost a third of your heart function because you've had a massive coronary blockage. If I were to at that point say, I could wave a magic wand right now in the hospital at your bedside. And if only you could go back 20 years and start investing in your sleep, instead of maybe adopting what some, not all people, but some have this sort of almost this, it's almost like a sleep machismo attitude.

1:21:59I think in certain sectors of the workplace, we've got this competitive under sleeping, you know, mentality, the sleep braggadocio notion. But I know no one who 20 years later in a hospital wouldn't say if I could go back and remove all of this cardiovascular consequence that you've just had by way of this heart attack, if only you'd gone back and started just to try to invest even just five or six days a week in consistent good sleep, would you do it? Most people at that point would say, absolutely, I wish I could take it back. But it's so hard for us to prospect into the future and do back casting.

1:22:40Many of us just can't do forecasting at all very well in terms of our health. So what do we do? We burn the candle at both ends. Also, I think it's not anyone's fault regarding this global sleep loss epidemic and this consistent sort of sleep neglect, because firstly, I think society is conspiring against us to get sufficient sleep because sleep has this image problem. We think of people who get sufficient sleep as slothful, as lazy, that sleep, whoever the PR agent for sleep has been, we probably should have fired them long ago because I'm going to try and push back at least. But also from a perspective of someone who doesn't know anything about sleep, I would just think, well, my body's at rest.

1:23:23My mind is dormant. How much danger is there really in losing one hour of sleep or even two hours of sleep? Surely there's not much danger. It can even actually change your very nucleic alphabet. So I'll tell you about a fascinating study that impressed upon me the importance. They took perfectly healthy individuals and they limited them to six hours of sleep a night for one week. By the way, six hours of sleep a night for one week is actually what many people are getting in society. At least a third of the population seems to be getting six hours or less during the week. So it was a very sort of ecologically relevant experiment.

1:24:03And 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. And there were two key findings. First, a sizable and significant and 711 genes were distorted in their activity caused by that six hours a night of sleep. If that wasn't impressive enough, the second was that about half of those genes were increased in their activity. The other half were decreased. Now, the genes that were increased in their activity were genes that were associated with biological stress and cardiovascular disease, genes that were associated with the promotion of tumors, and genes that were associated with long-term chronic inflammation within the body.

1:24:50Whereas those genes that were actually switched off or turned down were genes associated with your immune system. And so to me, what that demonstrated was that there's no aspect of our wellness that can retreat at the sign of sleep deprivation and get away unscathed. That it's almost like a broken water pipe in your home. That sleep loss will leak down into every knuck and cranny of your physiology and even tamper with the very DNA alphabet that spells out your daily health narrative. And so why, if you didn't know that evidence, why would you think that sleep is so necessarily important? If I just as a lay public person would be thinking, well, my mind's dormant.

1:25:36My body gets a bit of a rest. Well, I can rest when I'm watching Netflix. My body gets plenty of enough rest there, so I don't need my sleep. But if you think about it, sleep is the most idiotic of all evolutionary creations. You know, finding a mate, you're not reproducing, you're not caring for your young, you're not foraging for food, and worse, you're vulnerable to predation. Sleep should have been strongly selected against during the course of evolution if it wasn't important. It is absolutely important. It serves a constellation of different vital functions for brain and body. But if I didn't know about them, of course I'd neglect my sleep.

1:26:11So I'm simply saying that to both impress the importance of sleep, but also try to be compassionately sensitive to why I understand people neglect it, not because they're trying to show how brave and Teflon coated they are. it's just because no one understands sleep. So that's why I've tried to sort of make it impart a mission for life is sleep has been the neglected stepsister in the health conversation of today. We speak a lot about diet and exercise and that's great. And because of people like you, I think we're speaking so much more about emotional and mental health, which to me is the fourth pillar of life and health.

1:26:48Sleep is one of those pillars too though. So hopefully this helps a little bit. No, it's brilliant. Matt, I think you are the best PR agent. that sleep could ever ask for. I think your method of communication, the empathy and compassion that comes with it, the lack of judgment, and at the same time, waking us up to the reality, which I think is an important part of the narrative, comes across extremely clearly. And I'm so grateful. And I hope you'll come back on many, many times to deepen this discussion, to extend it. There's so much we didn't even get to today, but we end every On Purpose episode with a final five.

1:27:24and these have to be answered in one word or one sentence maximum. But I know I'm going to break that rule with you already. So the first question is, what is the best sleep advice you've ever heard, received, or given? Regularity digital detox. Going to bed at the same time, waking up at the same time. Do that. So many other things like quantity and quality will fall into place. And then the second is, as much as you can, in the last hour before bed, try to stay off your phone. And in the morning, give yourself 10 minutes. Why? Because what we do is we train ourselves. What's the first thing that most people do when they wake up?

1:28:06They open their phone. And there's this wave, the tsunami of anxiety comes flooding in. Every day you are training yourself when you go to bed at night to expect that huge wave of anxiety when you wake up. It's what we call anticipatory anxiety. And most people will have had this. You have an early morning flight and you know, you've got to wake up for it. It's essential. And you also know that your sleep that night will be so shallow and so sort of diminutive. Well, this is a diet version of that. But every single day by way of swiping open on your phone next to you, just give yourself 10 minutes in the morning.

1:28:46I promise your sleep will be better. So So regularity, digital detox. I love it. Question number two, what's the worst sleep advice you've ever heard, received, or given? That you can make up sleep at the weekend. You can't accumulate a debt and then hope to fully pay it off at the weekend. There's some great evidence looking at all sorts of brain and body metrics that for the most part, some of them, you can kind of sleep back at the weekend. But for the most part, when you look at your cardiovascular system, your metabolic system, your immune system, your hormonal system, if you look at your brain processes, your cognition, your emotional stability or instability, all of these things do not fully recover by way of weekend sleep.

1:29:29So you can't do this binge purge process. So I would say that the myth of makeup sleep is unfortunately just that, that it's not like the bank. Yeah. So you just have to get into a good rhythm and a good pattern and invest in it. It's just, it's never, yeah. If it was like that, trust me, you know, Mother Nature would have figured out a way to have us short sleeping all the time because sleep is so deleterious to any organism. And if there was a way to shortchange, we would have been shortchanging long ago and it would be baked into our sort of sleep DNA biology. The fact that it's not, that human beings are the only species that will deliberately deprive themselves of sleep for no apparent good reason is testament to the fact that you just can't make it up like that.

1:30:15The system doesn't work like that. Question number three, what does bad sleep do to your mental health? Firstly, you become much more emotionally erratic. You become pendulum-like. Why? Why is that? Yeah. Part of the reason is because there is a part of your prefrontal cortex right down in the middle. So my prefrontal cortex sits right above my eyes. It's the most evolved part of our sort of hominid brain. It's what makes us human beings. That middle part of the brain acts like almost a brake pedal on our emotional accelerator regions deep in the brain. And when we are underslept, that part of the brain gets shut down.

1:30:55So now we become all emotional gas pedal and too little regulatory control break, as it were. And that's why we become so reactive. We become, you know, it's that I just snapped dot, dot, dot, fill in the blank when I am under slept. So firstly, our regulation of our emotions becomes impaired as a consequence. Secondly, the anxiety centers of the brain can become 30 to 40 % more reactive when we're not getting sufficient sleep. You can flip that narrative then and say, well, if that's the bad that happens when I take sleep away, what is it about sleep when I do get it that is beneficial? And what we've discovered is that it's REM sleep or dream sleep that provides a form of almost overnight therapy.

1:31:44Dream sleep is emotional first aid. And it's during dream sleep that your brain takes those painful, difficult experiences and acts almost like a nocturnal soothing balm. And it just takes the sharp edges off those painful, difficult experiences so that we come back the next day and we feel better about them. It's that idea of it's not time that heals all wounds. It's time during sleep and specifically dream sleep that provides emotional convalescence. And there's a Wonderful. Gosh, I wish I'd come up with this quote by an American entrepreneur, E. Joseph Kosman. And he once said that the best bridge between despair and hope is a good night of sleep.

1:32:29That's exactly what dream sleep provides. If you love your family, the best thing you can do is get a good night's sleep. When you have had a good night of sleep, I think we all sense this. You wake up and you are dressed in a different set of psychological clothes. Absolutely. It's almost as though sleep provides this sort of emotional windscreen wiper benefit, and we can see clearly. And to me, that's, I think, one of the most powerful aspects. Sleep gives me back the rose in the tint of my worldview glasses every single morning. I mean, I experience that all the time. I know what I can be like if I haven't had a good night's sleep.

1:33:11Yeah, yeah. You know, I'll sometimes say that to my much better half, you know, when I wake up, I'll say to her, look, you know, darling, I am, I am so sorry. I didn't sleep well last night. I am not the best version of myself for whatever I do today, whatever idiocy that I, you know, enunciate or behave in. Yeah. Please forgive me. And I will make sure that I will do all the dishes for the next two months. Yeah. Sleep affects our emotional relationships, our intimacy, everything. Question number four. I have something in my mind. I was going to ask you, what have you seen as being a surprising connection that's connected to sleep?

1:33:49Something that sleep impacts that surprised you? Something a bit that we might not have heard of? We've done some studies looking at what I would think of as more complex pro-social behavior. And what we found is that a lack of sleep will immediately make someone become more asocial meaning that they withdraw socially. They do not wish to have the contact with other people that they typically do. They become therefore more isolated. They feel more lonely as a consequence. And we know that there is this epidemic of loneliness happening. We didn't realize how much a lack of sleep was contributing to that.

1:34:30Worse still, when you interact with someone who is sleep deprived and you are well rested, having had that interaction with the sleep deprived person, when we ask that person, do you feel any more or less lonely in this moment? They rate themselves as now feeling more lonely themselves, having interacted with a sleep deprived individual. In other words, the loneliness that a lack of sleep creates is contagious and it is transmitted from one person to the next. The second thing that we looked at was perhaps one of the most fundamental components of us homo sapiens, which is that we help each other.

1:35:12It's what we call pro-social behavior. And I cannot imagine any modern civilization that has emerged without pro-social helping between individuals. It's a fundamental ingredient. We help each other. And what we found is that when you are underslept, you withdraw your natural tendency to help other human beings. We observed it at the level of me helping other people. We observed it at the level of entire groups helping each other. And we also found it across entire nations. And you think, how do you figure that one out? There is a global experiment that's performed on 1.6 billion people across 70 countries twice a year, and it's called Daylight Savings Time.

1:36:01And what we did, we looked at the national donation database across the United States, which is in some ways a measure of selfless giving. I give to charity, I give to other people. And what we found is that in the days after the spring daylight savings time, when we lose one hour of sleep, there was this huge dent in proactive giving by way of donations to charities. We become more stingy. We become more self-centered. That's crazy. So I would say that it's this new wave of sleep science that goes beyond the DNA nucleus that we spoke about. It goes beyond cells. It goes beyond physiological systems.

1:36:43It goes beyond entire brain networks. It goes beyond the organism themselves. It now translates to a lack of sleep impacting our interrelationships and impacting the very fabric of society itself. That to me has been stunning and quite a surprise. That, yeah, that is a surprise. I was not expecting that. Fifth and final question we ask this to every guest who's ever been on the show, Matt. If you could create one law that everyone in the world had to follow, what would it be? Self-forgiveness. Why? Because I think that there is so much ill grace that is enacted by ourselves on others because we are not good with ourselves that it makes me sad at some times.

1:37:32And I think so much of what we react to others is really about a mirror being held up to ourselves and the pain of that, that if we just let go and gave ourselves self-compassion and self-forgiveness, society would be, I think, demonstrably, which is to say demonstrably, better as a result. In truth, though, that's probably me just holding a mirror up to myself to your question. Beautiful. Matt, thank you so much for your incredible work, incredible sharing of insights today. And I really hope you'll come back for another episode because I have another million questions to ask you. Thank you so much.

1:38:14I'm so grateful for your time and energy. I hope everyone who's been listening and watching back at home, at work, whether you're on a hike, whether you're with your dog, whether you're driving right now, wherever you are, I hope that you will find it possible to try some, just one, even if you just try one of Matt's suggestions today, I really truly believe your life will change. And as Matt said, it will impact all other areas of our lives. Please prioritize your sleep and watch how your life changes. Thank you so much, Matt. Thank you. And can I just say thank you to you for what you do for society.

1:38:49You have dedicated yourself to the wellness and the health of the rest of humanity. But what I see as a big differentiator is that you have a very genuine passion for doing this. You mean it when you say it. Thank you. And I think that's why in part you've had just this incredible impact on society. Authenticity is a very rare thing. And as human beings, we're actually very good at identifying it and also identifying its absence. And one of the reasons that I just have such admiration for what you do is not just that what you're doing is an incredible service, but the authentic way that you're doing it because you genuinely mean it is something that I think is a remarkable beauty to behold.

1:39:37So for all that you do for society, thank you so much. Well, thank you, Matt. That's extremely gracious and kind. Genuinely, that touched my heart. Thank you so much. Thank you. If you loved this episode, you'll enjoy my interview with Dr. Daniel Amen on how to change your life by changing your brain. If we want a healthy mind, it actually starts with a healthy brain. You know, I've had the blessing or the curse to scan over a thousand convicted felons and over a hundred murderers, and their brains are very damaged. Parking shouldn't slow you down. ParkWiz gives every driver a shortcut. Book ahead, save up to 50%, and skip the hassle of circling the block.

1:40:20Park smarter, park faster. ParkWiz. Download the ParkWiz app today and save every time you park. There's a lot going on in Hollywood. How are you supposed to stay on top of it all? Variety has the solution. Take 20 minutes out of your day and listen to the new Daily Variety podcast for breaking entertainment news and expert perspectives. Where do you see the business actually heading? Featuring the iconic journalist of Variety and hosted by co-editor-in-chief Cynthia Littleton. The only constant in Hollywood is change. Open your free iHeartRadio app, search Daily Variety, and listen now. Ugh, come on.

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From the publisher

How well did you sleep last night?

Do you wake up feeling rested?

Today, Jay welcomes renowned neuroscientist, sleep expert, and bestselling author Dr. Matthew Walker to unpack the profound importance of sleep and how it shapes every facet of our health and wellbeing. Bestselling author of Why We Sleep, Dr. Matthew Walker brings scientific rigor and heartfelt clarity to one of the most misunderstood and underestimated aspects of our lives.

Matthew opens the discussion by challenging the myth of the 'eight-hour rule.' While the average adult does best with seven to nine hours of sleep, the focus quickly shifts beyond just duration. Instead, Matthew introduces a more holistic four part framework—Quantity, Quality, Regularity, and Timing, or QQRT. This framework highlights how sleep is not simply about how long one sleeps, but also how deeply, how consistently, and how well it aligns with our natural biological rhythms.

Jay and Matthew's conversation also tackles common disruptors of restorative sleep, including caffeine, alcohol, and excessive exposure to artificial light. Dr. Walker discusses how these elements can interfere with the brain’s ability to enter deep and REM sleep, the latter being especially important for emotional processing, hormonal regulation, and memory consolidation. Sleep, it turns out, influences far more than individual health. 

In this interview, you'll learn:

How to Know If You’re Getting Enough Sleep

How to Improve Sleep Using the QQRT Formula

How to Align Your Sleep With Your Body’s Internal Clock

How to Avoid Waking Up Tired Every Morning

How to Optimize Your Evening Routine for Better Sleep

How to Fall Back Asleep After Waking Up at Night

How to Diagnose Sleep Apnea at Home

With scientific insight and practical wisdom, the episode paints a vivid picture of how sleep, when prioritized and protected, can serve as a catalyst for healing, clarity, and sustainable energy.

With Love and Gratitude,

Jay Shetty

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What We Discuss:

00:00 Intro

01:12 The Four Metrics That Define Great Sleep

06:03 Can You Actually Change Your Sleep Cycle?

09:45 Why You Wake Up Tired—Even After a Full Night’s Sleep

14:29 What Sleep Apnea Really Is and Why It’s Often Missed

19:21 The Body-Wide Damage Caused by Sleep Loss

23:20 The Hormone That Increases Late-Night Cravings

28:42 Best Types of Food to Eat Before Bed

33:48 How Late-Night Eating Disrupts Your Sleep Rhythm

37:23 The Truth About Melatonin Supplements

40:47 Should You Give Melatonin To Your Children?

44:25 The Evolution of Sleeping Pills Explained

52:36 The Best Nighttime Routine For Optimal Sleep 

55:07 Three Practical Tricks to Fall Back Asleep

01:04:58 What It Really Takes to Clear Caffeine From Your System

01:08:01 Surprising Health Benefits of Drinking Coffee

01:10:02 How Alcohol Quietly Ruins Your Sleep

01:13:06 Can Sleeping Well Actually Make you More Successful? 

01:16:40 The Real Risks of Losing Just One Hour of Sleep

01:21:16 What Regular Sleep and a Digital Detox Can Do For Your Life 

01:22:45 Why Weekend “Catch-Up” Sleep Doesn’t Work

01:24:09 The Overlooked Link Between Sleep and Mental Health

01:27:32 How Poor Sleep Fuels Loneliness and Disconnection

01:30:58 Why Self-Forgiveness Might Be the Ultimate Sleep Tool

Episode Resources:

Matthew Walker | Website

Matthew Walker | Instagram 

Matthew Walker | LinkedIn

Matthew Walker | X

The Matt Walker Podcast

Why We Sleep: Unlocking the Power of Sleep and Dreams

See omnystudio.com/listener for privacy information.

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