Feel Better, Live More with Dr Rangan Chatterjee - #250 Why Sleep is the Most Important Pillar of Health with Professor Matthew Walker (Re-Release)

Episode Date: March 27, 2022

This is the first in a series of re-released episodes from the Feel Better Live More back catalogue. I originally recorded this conversation over 4 years ago and Professor Matthew Walker is one of our most popular guests on the podcast. Sleep is one of the most undervalued components of our health yet neglecting it can have devastating consequences. In this episode, I talk to world-leading sleep researcher, author of the international best-selling book Why We Sleep and Professor of Neuroscience and Psychology, Matthew Walker. We discuss everything you ever needed to know about sleep. Matthew shares some brilliant tips to combat jet lag, explains how sleep can enhance athletic performance and decrease risk of injury and reveals just how much caffeine consumption can impact sleep. We explore the reasons behind the current global sleep-loss epidemic and how sleep deprivation can affect every aspect of our health – from our blood sugar levels and our risk of heart attack to our mental health. Finally, we discuss alcohol’s impact on sleep and the staggering financial costs associated with lost sleep. Matthew also shares what he has changed in his own life since starting his research. This is an invaluable conversation – I hope you enjoy it! Thanks to our sponsors:   https://www.vivobarefoot.com/livemore   https://www.athleticgreens.com/livemore Order Dr Chatterjee's new book Happy Mind, Happy Life: UK version: https://amzn.to/304opgJ US & Canada version: https://amzn.to/3DRxjgp  Show notes available at https://drchatterjee.com/250 Support the podcast and enjoy Ad-Free episodes. Try FREE for 7 days on Apple Podcasts https://apple.co/3oAKmxi. For other podcast platforms go to https://fblm.supercast.com. DISCLAIMER: The content in the podcast and on this webpage is not intended to constitute or be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your doctor or qualified health care provider with any questions you have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have heard on the podcast or on my website.

If you look across epidemiological studies, millions of individuals in these studies, a very simple truth comes out, which is that the shorter your sleep, the shorter your life. That short sleep predicts all-cause mortality. You know, the global sleep loss epidemic that is underway right now, which I believe is probably one of the greatest public health challenges that we now face in the 21st century, it is a slow form of self-euthanasia. Hi, my name is Rangan Chatterjee. Welcome to Feel Better, Live More.

If you are a regular listener of my show, you will know that the usual pattern of release for this podcast is a new conversation every Wednesday and a shorter 10-minute bite-sized episode every Friday. But over the next few weeks, what I've decided to do is re-release some of the most popular podcast episodes to date at the weekends. Now, the reason I've decided to do this is because at the moment, there are a lot of new listeners coming to this show. And that's because there's a lot of publicity in the media, the newspapers, on television, and on other people's podcasts surrounding the release of my brand new book, Happy Mind, Happy Life. So for new listeners, I really want to be able to showcase what this podcast is about

and the variety of different topics that I try to cover every week. Now, if you're a long-time listener, I hope that you will enjoy being reminded about some of the classic episodes from the archive. And even if you did enjoy listening to the episodes first time round, I hope that you might feel inspired to re-listen. the episode's first time rounds, I hope that you might feel inspired to re-listen. So the first conversation in this new weekend series is my initial conversation that I recorded now over four years ago with the author of the international bestseller, Why We Sleep, Professor Matthew Walker. Now Matthew is a fountain of knowledge when it comes to all

things sleep, but he also has a really compelling and clear way of sharing his ideas and research. And when our conversation, we talk about sleep potentially being the most important pillar for our health, the impacts of caffeine and alcohol on the quality of our sleep. We talk about sleep and athletic performance and how better sleep can help reduce our risk of injury. We also talk about the type of sleep that is most effective for our mental health and resilience and how being chronically sleep deprived affects our appetite and our ability to lose and burn off fat. This really is an incredible conversation that I think is just as relevant today as it was when I recorded it four years ago.

I hope you enjoy listening. that I think is just as relevant today as it was when I recorded it four years ago. I hope you enjoy listening. But caffeine is a misunderstood drug. It's a drug, right? You use the term drug, and that's interesting. It is a drug. It's what we call a psychoactive stimulant. Everyone knows that caffeine can help alert you and sort of keep you awake. That's the thing that's most known. Caffeine, if you look at some data, is probably the second most traded commodity on the surface of the planet after oil, which I think says everything about our sleep deprived state.

The other thing about caffeine, however, that most people don't realize is the time that it is in your system. So most drugs have what we call a half life, the amount of time it takes for half of that drug to be essentially excreted out your system. Caffeine has a half life of about six or seven hours, and it's a little dependent on what type of gene that you have to sort of metabolize the caffeine. But on average, it's about that. But what's interesting is that caffeine has a quarter life of about 12 hours. What this means is that if you have a cup of coffee at noon, a quarter of that caffeine is still circulating around your brain at midnight. So to put that in context, it would be the equivalent of getting into bed. And just before you turn the light out, you swig a quarter of a cup of Starbucks and you hope for a good night of sleep.

You know, you would never do that because, you know, but that's exactly, unfortunately, what people do, you know, completely innocently by drinking caffeine, you know, still too late in the afternoon. Yeah, it's a huge problem. still too late in the afternoon. Yeah, it's a huge problem. I think it's a big problem in society. I mean, another way to quantify this is if you just look, and I've checked out the data from the Financial Times, the number of Starbucks coffee houses that have arisen over the past 30 years is just like an exponential increase.

And I think that is an expression of how we're self-medicating our state of sleep deprivation in developed nations. Well, cafe culture is just growing exponentially now, right? It's the new, you know, I talk about something, it's almost like a new pub culture. It's cafe culture. You hang out with your friends, you meet up, you get your drink. Typically, it'll be a caffeinated drink.

We've now got school kids. You know, I saw in a local village I was walking through recently, you know, after school, you know, I popped into a cafe to get, I think, a bottle of water. I can't remember, but I popped in and I saw a group of school kids. They must have been maybe 13 or 14 after school. They have sitting in the cafe with their caffeinated drinks, you know, doing their homework together, catching up or whatever. I thought, wow, this has become endemic in society now. You call it a drug. I agree with you. It is a psychoactive substance that we use liberally. We let our children have it. We often don't think about the implications

of that. And so many patients of mine tell me that, Dr. Chachi, I know, you know, if caffeine can be a problem for some people, I'm not one of those. Caffeine is fine for me. But more often than not, when they either reduce their intake or cut it out completely, the sleep quality goes up. And, you know, Sachin Panda, Professor Panda, who, you know, I know you know very well, you both sort of follow each other's research he was on the podcast a few weeks ago and you know he was saying routinely every year he will he will have a bit of a detox from caffeine he'll go off caffeine he says when I do that yeah I have a headache for a few days but my sleep always improves I've got more energy and my productivity dramatically increases and I think that says it all, really.

It does. And, you know, a number of points that you made that I'd love to circle back around to. Firstly, caffeine is the only psychoactive stimulant that we do give to our children readily, which, you know, is, I think, a concern. And I'm not trying to be sort of, you know, finger-pointing or finger-wagging. Again, I think it's just that parents

probably don't understand the impact of caffeine in that regard. I think the second point comes on to your comment of some people say, look, I'm one of those people who can drink a cup of coffee in the evening, have an espresso after dinner, and I fall asleep fine and I stay asleep. Now, even if that's true, there was an alarming study that was done where they gave people just one single cup of coffee, a dose of 200 milligrams of caffeine, standard cup of coffee. And then they measured the quality of their deep sleep by tracking these big, powerful brainwaves, these glorious, beautiful, deep brainwaves that bathe all of our brain during deep sleep at night. And it helps also restore the body. night and it helps also restore the body. And what they found was that just one dose of caffeine in the evening decreased the amount of deep sleep by 20%. Now you would have to normally age by about 15 years to produce that type of a deficit in your deep sleep, or you can do it every single night by having a cup of coffee. And what's interesting is that those people will wake up the

next morning. They won't remember waking up because they may not have woken up, but the quality of their deep sleep was so poor that they will still then feel unrestored and unrefreshed by their sleep. And so here is the irony that now they're starting to reach for two cups of coffee rather than one. And so develops this dependency cycle, this sort of addiction spiral, as it were. So I think people are perhaps unaware of the true impact of caffeine, how long it sticks around within your system. And even if you feel that you're immune to that evening cup of coffee, how it will still impact your sleep, even though consciously you know nothing about it.

Well, I think, you know, you raise a really important point there, Matthew, about, you know, knowledge and awareness. You know, none of us are pointing fingers. You know, we, you know, I understand caffeine is everywhere. You know, I probably used to overdrink caffeine and I've altered my behaviour as I've learned more and more about the research. And I think what we're trying to do is raise awareness of, you know, caffeine is a sleep disruptor. There's just no question about that. And, you know, we can dress it up any way we want, but it is a sleep disruptor. So if anyone is listening to this, if that story that Matthew just mentioned resonates with you, I'd

really sort of encourage you to have a little think about your caffeine usage and just see if, can you, can you wind it down a little bit? Can you see, you know, bit by bit, if by reducing it, it improves your quality of sleep? The recommendation I make in my book is enjoy your caffeine before noon. And I say enjoy, because I get it. People love it. I love a good cup of coffee, but I will not have caffeine after midday. Yeah. And I, you know, I've now actually done what Sachin has done. I would, I routinely go through sort of a caffeine detox. And right now I'm caffeine free, but, you know, I too would enjoy that cup of coffee or a nice strong cup of, you know, Yorkshire tea. I have no relationship with them, by the way, in the mornings. And I also love the coffee culture as well. You know, I go out with friends and we grab coffee all the time and I love

that. And I want people to embrace it because I think it's fantastic that there's a social movement sort of circulating around that. All I would say, though, is that, you know, decaffeinated coffee is actually really quite good. And I would struggle, I'd love to do the sort of, you know, the Coke Pepsi challenge with decaffeinated. Just in terms of the taste, you will probably notice that it wouldn't give you sort of the shakes or that sort of slightly anxious state, and you probably know the difference. But I've really become enamored with decaffeinated coffee and all of its flavors,

and I love the cafe bar culture. So love to embrace that. But I do like what you're saying about sort of patients just thinking a little bit about caffeine and considering it and just trying to try the experiment, you know, sort of set yourself the task, give it a go and see if it works for you. Yeah, I remember about a month after my book came out, someone tweeted me and said, I never ever thought that caffeine was a problem for me. But I've read your book, I've taken your recommendation, I now only have two cups of coffee and I have it before noon. And I've never slept this well in over 30 years. And it's just incredible how such a common thing that people are doing day to day may be impacting our sleep. And I think you make a really good point that it's like a self-fulfilling prophecy. The more caffeine you drink, the more

you need, the more dependent you become, the less good your sleep is. And it just continues. I think we also have to highlight, we're talking about coffee, but I think tea would be similar because it contains caffeine. Green tea, a herbal tea that often people switch to when they're not having tea or coffee, is also a highly caffeinated drink, so may affect you. You mentioned decaf coffee. You know, I've read some reports are saying that decaf coffee does contain some caffeine. Do you know much about that? So decaffeinated coffee is not no caffeinated coffee.

So you do have to be, you know, somewhat mindful of that. And they looked and you can sort of search around on the internet. There's some good sites that will describe exactly how much some brands have very little caffeine at all. Other brands, however, I was surprised to find can have up to 20% caffeine in. So you have five cups of those, you know, and you're well on your way to a standard cup of coffee. So you do have to be a little bit careful. But it's certainly a good way if you're thinking about trying to come off caffeine to sort of psychologically still treat yourself with that. Exactly. And it tastes great, right?

Yeah, it does. It really, it's not too bad. So caffeine is something that a lot of us do in the morning. We're also going to talk a little bit later about alcohol, which is something that people often use in the early evening or late evening to help them unwind for bed. But before we go deep into alcohol, because I think that's something that people are incredibly fascinated about, because I think that whole term of the nightcap, it's there in our vernacular now,

how it's something that can help you just slip off into sleep. Or can it? We'll find out shortly. But, you know, listeners to my podcast know that I talk about these four key pillars of health that I think have the most impact on the way that we feel, but also that we've got some degree of control over food and movements, which people have been talking about for years, but also sleep and relaxation. Now, in your book, right at the start, you make a very powerful case why sleep is the foundational pillar of health. I'd love you to talk more about that. Yeah, you know, I used to think that sleep may be the third pillar of good health alongside diet and exercise. But the more I sort of did my research and the more I read from other people, I realized I was probably wrong. That in fact, sleep is the foundation on which those two other things sit.

you an example in each. Firstly, for diet and exercise, we know that if people are trying to lose weight and they're being judicious about their food intake, they're trying to diet, but they're not getting sufficient sleep. 70% of all the weight that they lose will come from lean muscle mass and not fat. Wow. Because your body becomes very stingy in giving up its fat when you are underslept. So dieting becomes, you know, quite redundant in that regard. You know, you want to keep the muscle, you want to let go of the fat and sleep deprivation will do the opposite to you. So that's the first thing. It's a foundational element on which, you know, nutrition sits. And by the way, I'd love to talk all about sort of diet, appetite, sort of increased caloric intake, increasing exactly what you desire to eat when you're underslept. There's great data there.

But let me move over to activity. We've spoken about the foundation on which diet sits. When you are not sleeping sufficient amounts, firstly, the likelihood that you will actually exercise decreases significantly. Your motivation to be physically active drops away. Even if you are physically active, the intensity of your workout will not be as strong. So it's less effective and less efficient. Things like your vertical jump height, your muscle contraction strength, even the exchange of carbon dioxide and oxygen in your respiratory systems, they get worse when you haven't slept. What's even more frightening,

however, is that your risk for injury increases when you are exercising but not well slept. This is incredible. And they did this great study where they looked at some athletes across a season, and then they tracked their sleep. And then they bucketed those athletes into the different amounts of sleep, nine hours, eight hours, seven hours, six hours. What they found was a linear relationship between less and less sleep and increasing risk for serious injury during a sports event. So there is yet another demonstration of how even if you're trying to be physically active but not getting sufficient sleep, it can be harmful. The beauty of that part of the relationship and the same for diet

is that it's bi-directional, that if you actually, you know, improve your sleep, you can improve those two things. But conversely, those two things will improve sleep. So if you start to correct your diet, you start to sleep better. We've already spoken about caffeine, but physical activity is a great way to enhance both the quality and the quantity of your deep sleep. So physical activity, as long as it's not too close to bedtime, if it's too close, your metabolic rate stays too high, your core body temperature stays too high, and that will prevent sleep. I'm seeing that a lot as well you know and I've experienced that myself in terms of squash is one of my favourite games but if I play squash at about 7 or 7 30 p.m I can't sleep that night you know I'm lying in bed at night I know it's about five-ish for me really is the last time I can go on the squash court

have a great workout have have an enjoyable game, and everything seems to have sort of gone back down to normal before I try and sleep at night. And I've seen that a lot with patients, which again, you know, if people are after work, they're trying to fit their workout in, you know, it becomes challenging because the modern world is making it sometimes quite tricky for us to live in harmony with our natural circadian rhythms. But I see that a lot working out intensely in the evening is a problem. If you don't research on that in your lab. So we've looked at this with body temperature too, you know, and I understand that people, you know, I still want to celebrate and embrace the idea of people exercising. I think that's critical. And even if it's late into the night, best not to do that. But if you do do that, a good way to try and solve the higher core body temperature is to have a bath or a shower right before bed.

A hot bath, right? A hot bath is best, yeah, or a hot shower. Because what happens is that all of the blood comes to the surface of your skin. You kind of get nice rosy cheeks. surface of your skin, you kind of get nice rosy cheeks. And that acts like this huge thermal radiator taking all of the heat out of the core of your body. And as a consequence, the core body temperature will actually plummet and you will fall asleep easier. That's the reason that it's always easier to fall asleep in a room that's too cold and too hot. Too cold is taking you in the right temperature direction for good sleep. So if you do have to work out at some point late into the night,

you can try that trick. But for the most part, try and get your workout in a little bit earlier. It's a great tip, though, for people, because I know there'll be many people listening to this who probably do try and get their workout in in the evening. So that's a great little tip that they can put into practice to see if they can ensure that that workout doesn't hinder their ability to get good sleep. As you were talking about vertical jump and, you know,

you know, as a sportsman myself, I sort of, you know, this really, you know, gets me excited to think actually, can you improve your performance by sleeping more? And immediately what came into my head is an interview. I think it was an interview or maybe I heard this comment I mean you may may know more about this but I have heard that Roger Federer may get I think he's been on record say he gets 12 hours of sleep a night I don't know that's true or not have you heard about that at all yeah yeah so he does he gets about uh 12 hours of sleep and if you look at lots of sports athletes, you know, LeBron James, the basketball player, he suggests that he gets somewhere between 10 and 11 hours. He splits that

he has a nap routinely during the day of about an hour and logs about sort of nine to 10 hours at night. Usain Bolt, you know, he is, he says he never gets anything less than nine hours. And I believe for one of his world records, he had only been awake for about 35 minutes because he'd taken a nap right before. I think it was an Olympic gold and a world record that he broke. And he'd only been awake for about 35 minutes because he'd slept. And, you know, this is what, you know, I do some consulting now for some Premier League football teams as well as NBA, NFL in the United States. Because they're starting to realize that sleep is probably the greatest legal performance enhancing drug that you could ever wish for. And it's not just in terms of preparation for exercise, by the way, for which it is spectacular. It's also about recovery. And that's one of the places where I see a lot of their sports physios perhaps not recognizing what they can do with sleep.

They front loaded about before the game, which is great. But often when teams are playing, they're playing multiple games. It's about a season and it's all about maintaining their players' health. And that recovery period after a game before you play the next game is key. You know, players will dive into baths of ice to try and reduce swelling and inflammation. Sleep is a critical part of that sports equation. You need to sleep on both sides of that. So it's fascinating.

Just, I say it just for people who are, you know, really interested in being physically active, maintaining their peak performance, make sure that you also consider sleep after being physically active as well. When we talk about peak performance, you know, everyone's looking for peak performance these days. Of course, those guys are athletes, right? So their idea of peak performance is probably, you know, when Roger Federer is playing in a grand slam tennis match he wants to be operating at peak performance but you know like you know joe public also wants peak performance in their lives you know they want to be able to wake up feeling refreshed you know maybe get their kids to school without there being a whole load of arguments at home because everyone's underslept and tired. They want to get to work and perform well in their

job. So they feel that they're contributing to whatever work they're doing. They're operating at a high level. So, you know, I guess, you know, some people may think, yeah, Roger Federer, LeBron James, you know, yeah, sure. Great for those guys. But, you know, I don't need as much sleep as them. So my question would be, what can we learn from those guys then in terms of how they prioritise sleep? How much sleep do we need every day? But also, in episode 14 of this podcast, it was a few episodes ago, I interviewed Nick Littlehails, who for many years has been advising clubs like Manchester United, the England football team. And he talks about this idea of 90-minute sleep cycles.

I don't know if you've read his book or you're familiar with his recommendation, but I find it, you know, he talks about this whole idea of five 90-minute cycles that we need throughout the day. And I know some people found that quite helpful to take the pressure off them at night. So quite a few questions there, Matt, but I wonder if we could just try and go into those areas a little bit. Yeah, so right now the recommendation is for most adults get seven to nine hours of sleep. And to get, by the way, to get seven hours of sleep, you probably need at least a seven and a half hour sleep opportunity. I think that's what many people miss in recommendations from sort of experts. They say, get your seven hours of sleep. So people think that means, you know, well, if I go to bed at 11 p.m. and I wake up at 6 a.m., then I've got my seven hours

of sleep. That's not true. You probably will have only logged about sort of six hours and 40 minutes and that's not enough. So you need to think about the sleep opportunity time as being probably around about eight hours optimally. What we also know is that once you get below seven, we can start to measure objective impairments in your body and in your brain as well. The problem is that most people don't realize that they're sleep deprived when they're sleep deprived. This is a big problem with sleep loss. And, you know, the analogy, I guess, would be a drunk driver at a bar. You know, they've had a couple of pints, maybe a few shots, and they pick up their car keys and they say to you, you know, look, I'm fine to

drive home. And you say, no, I know that you think you're fine to drive home, but trust me, you're not. You are objectively, you're impaired. It's the same way with a lack of sleep that our subjective sense is a miserable predictor of objectively how well we're doing with a lack of sleep. And I think that's one of the issues that I try to sort of help dismiss in terms of a notion. I think the other thing that's problematic too about getting too little sleep is that your baseline level of how you think your health and your wellness is just becomes chronically low. And you accept that as if that's just where I am in life. This is just me. This is as good as it can be. And people don't realise that if you were to change something like sleep or stress or diet or physical activity, there's actually a better form of you waiting

on the other side of those things. It just requires perhaps, you know, some knowledge and an invitation to go there. Matthew, I call this podcast, Feel Better, Live More, for a reason. And it really just echoes what you just said then. When we feel better by prioritising sleep, by looking at these other pillars that I talk about, we get more out of life. We're a better version of ourselves. We have better relationships. We have much deeper, more meaningful interactions with the world around us when we're feeling better. And I guess you would argue that when we sleep better, we live more. We do. I mean, firstly, that data is very clear that if you look across epidemiological studies,

millions of individuals in these studies, a very simple truth comes out, which is that the shorter your sleep, the shorter your life. That short sleep predicts all-cause mortality. Wow. And so, you know, I think... I think we just need to stop and just let that sink in for a minute. Depriving ourselves from sleep will shorten our life. Yeah. Yeah, I mean... That's the powerful data that, you know,

the global sleep loss epidemic that is underway right now, which I believe is probably one of the greatest public health challenges that we now face in the 21st century, it is a slow form of self-euthanasia. That's a very powerful statement, one that I absolutely would agree with. Have we, as a society, have we put too much focus on the right food and the right physical activity at the expense of sleep. show. Now if you're looking for something at this time of year to kickstart your health, I'd highly recommend that you consider AG1. AG1 has been in my own life for over five years now.

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offer. Usually, they offer my listeners a one-year supply of vitamin D and K2 and five free travel packs with their first order. But until the end of January, they are doubling the five free travel packs to 10. And these packs are perfect for keeping in your backpack, office or car. If you want to take advantage of this limited time offer, all you have to do is go to drinkag1.com forward slash live more. That's drinkag1.com forward slash live more. thought about this a lot. I don't think we've done it at the expense of sleep perhaps, but I do resonate with your comment that I think sleep has perhaps been the neglected stepsister in the health conversation of today. And I think it's been left out in the cold. There's probably a number of reasons for that. The first is just because scientists like me are to blame. What I

mean is that we have not adequately communicated to the public or to medicine or to healthcare professionals in general how critical the importance and necessity of sleep is. And I liken where we are with sleep with where we were for smoking 50 years ago. All of the science was there, but it hadn't trickled down into the public knowledge base or even into medicine. That's what you do so great with your book is you're bringing that awareness to the general public all over the world, which is fantastic. And that was part of the motivation for the book.

I could see the disease and sickness and ill health that was caused by insufficient sleep. And there wasn't a blueprint guide, there wasn't a blueprint guide. There wasn't some kind of a manifesto for sleep. And so that was part of the reason to write the book. But I think to come back, you know, to why sleep has been left out in the cold, I think part of it is people like, you know, well, at least my fault. I think the other thing, too, is that unlike diet and exercise, sleep has an image problem. You know, I think nobody feels ashamed about saying, I went out for a run at lunchtime or, you know, I had a great run this morning. Nobody necessarily feels ashamed about, you know, putting salad on their plate, you know, and making a really healthy meal. But I do think people feel sometimes ashamed by saying,

well, I need at least eight and a half hours of sleep a night. You know, and sometimes I've heard the reaction of people saying, really? And that really has a hint in it to suggest that if you're getting sufficient sleep, and I choose that word carefully, sufficient, then you must be lazy, that you're slothful. Because we've tagged and we've associated this thing called necessary sleep with that luggage of something to be ashamed about. And in fact, if anything, what happens is that people have this braggadocio attitude, this almost sort of sleep machismo attitude that you're very proud to tell people how little sleep that you're getting as though it's, you know, a badge of honor. I see that in some people, not all people, but some people. So I think to change that part

of the sleep discussion and bring it into the health equation, we need to de-stigmatize sleep in a way too. I think those are at least two of the reasons why it's being left out in the cold. Yeah, yeah, absolutely. I mean, I, you know, I've shared this before on the podcast that a few years ago, for me, it was probably when I had kids, actually, because my kids were early risers. And, you know, that's, that's the understatement of the year that they were early risers. But I realized that if I didn't alter my going to bedtime, I was going to be exhausted every single day, which is what was happening. And I sort of altered my whole sleep schedule a few years back.

And it's something now that I really do prioritise. I will have a shut-off time in the evening, after which I'm not on my computer, I'm not working, I will wait because I know that if I don't do that, the next day I won't be performing at anywhere near the level I want to. And it actually reminds me of that Facebook conversation we had, the Facebook live chat we did. So guys, we were trying to schedule this chat for a little while. Oh, I love this.

We put a date in and then Matthew had to move the time and I got an email, I think, from your publicist saying in and then Matthew had to move the time. And I got an email, I think, from your publicist saying, you know, can we move this time? And I thought, well, that's 9pm UK time. Man, that's really late because, you know, I've just written a book saying how important sleep is as well. I'm, you know, trying to educate and inspire my audience that actually these things are really important. So I actually declined your very kind invitation to do it at 9pm. I just actually asked to see if we could change the time. Yeah, you probably didn't know.

Yeah, I certainly wouldn't have suggested that. Yeah, I said, guys, look, we chat between 9 and 10, and we talk about how detrimental sleep is and all the problems associated with it, yet we're doing it late in the evening for my UK audience. I'm going to expose everyone to blue light in the evening right onto online devices emotionally work them up before beds i thought actually you know what let's just decline that and do it another time so i thought that was quite nice yeah that was great wasn't it yeah it was just you know for someone to embrace

you know sort of uh and practice what they preach you know, and I think for the two of us, you know, a lot of people, of course, will ask me, well, so how much sleep do you get? And I will tell them that I do honestly get a non-negotiable eight hour sleep opportunity every night. And it's, I'm not trying to be, you know, a poster child for sleep. I'm not trying to just sort of promote the book. If you knew the data as I do, and as I hope people will after reading the book, honestly, you just would not choose to do anything

else. And, you know, I don't want to live a shorter life and I don't want to live a shorter life that is filled with disease or sickness. And from everything I can tell, sleep is perhaps one of the most democratic, freely available, efficacious forms of health insurance that you could ever wish for. And as a consequence, the reason I get that much is because for selfish reasons, you know, I just want to be alive and well for as long as possible. And I think, you know, it's interesting hearing you say why you prioritize it. You know, again, it's selfish is the wrong word, but it's for self-preservation reasons. And one of the things I actually, if I, if you don't mind, I know this is your podcast and you're interviewing me.

Talk about whatever you want. But I would love to just ask you the question, because, you know, when I saw the title of the book, you know, and I saw that, you know, there on the front cover was this word called sleep. On my book? On the front cover of your book, there was this thing called sleep. Relax, eat, move and sleep. And I well imagined that the first three would be there, of course, from, you know, an eminent clinician, but I was surprised by the four. I was lovely excited. It was wonderful. But tell me, you know, where did that decision come from to include sleep? You know, where did you get the awareness from? Where did you get the sensitivity to sleep?

You know, was it boots on the ground with patients was it in a medical curriculum was it personally tell me i'd love to know yeah i think matthew that's a great question really i mean my i guess my journey into this um i've really been keen to promote lifestyle comes from a you know a real feeling that in medicine we've lost our way a little bit. Now, we're not putting blame on anyone, but I sort of feel that the medical system is set up around acute diseases, acute problems that respond very well to our magic bullet

pharmaceutical interventions. But I think the health landscape, even in my career, and I've nearly been seeing patients now for about 20 years, even in my career I have I've nearly been seeing patients now for about 20 years, even in my career, I've seen the health landscape of the patients that I see change dramatically. Whereas now the bulk of what I see in my daily practice, I say 80% of it is in some way driven by our collective modern lifestyles. And so I've been delving deep for a few years now in terms of, you know, what are those lifestyle factors that I can leverage with my patients to get a better outcome? And of course, when I first started going on this journey, it was all about

food, right? You know, it's like, okay, you know, it's all about diet. You know, if we were having this chat five or six years ago, I would be saying, you know, most of what happens to us, you know, most of our health determinant is basically foods. But I be saying, you know, most of what happens to us, you know, most of our health determinant is basically foods. But I disagree now, you know, because I think when you know the science, when you have seen the science, as you detail so beautifully in your book, the case is compelling. You can't really ignore sleep. So I'm a doctor who wants to get my patients better, like every other doctor. I want to do this in as harmless a way as possible. And I'm a doctor who wants to get my patients better like every other doctor. I want to do this in as harmless a way as possible. And I also get very tired of suppressing downstream

symptoms. So I want to go upstream as far as possible to see what lever can I turn that's going to have all these downstream consequences. And food is one of those things that, you know, food isn't just calories, you know, it's not just fat and carbs, it's information. It changes our genetic expression. So it's information for the body. In a similar way, physical activity can change hormones, can change genetic expression, all these kinds of things. And, you know, so obviously that's food, that's movement. Relaxation is a whole piece about stress, which some research is showing that up to 90% of what we see in primary care may have stress as a factor,

which is incredible. But I always felt I was missing one piece off the puzzle. And I would see, if we take autoimmune disease as an example, when I see my patients, I often do what's called a timeline. And I look, you know, I say, okay, you've got symptoms here today, but let's look at your whole life. Let's see what's been happening sequentially. Because I don't think a lot of these chronic conditions just happen overnight. There's been a buildup for a period of time, for a period of years. And I would often see with autoimmune conditions that just a few months, sometimes just one month before the onset of symptoms, I would see either... Well, not either. I would

often see a really stressful episode happen that would reduce the quality of people's sleep. And then I see symptoms come on. As a doctor, I always want to learn from my patients. So your question is, where does this come from? Well, primarily it's come from listening to my patients and listening to the stories that they tell me. Because you're one of the world's eminent researchers of sleep. I love research, but I also love real life. What happens at the coalface when I'm seeing patients? What do they tell me is working? What do they tell me they're struggling with? That also influences a lot of my recommendations as well as the science.

You know, if you can marry those two together, I think that's when we can make a real difference with people. And I also went to a conference in San Diego about two years ago, and the whole conference was on sleep and relaxation and rest. And I think it was Phyllis Zay. Do you know Phyllis? Phyllis Z. And I think it was Phyllis Zay. Do you know Phyllis? Phyllis Zay.

Yeah. She gave a couple of keynotes there. And I thought, God, this really is wetting my appetite. It's really reinforcing what I'm seeing in my practice. As I say, when you look at the research, I thought, well, how can I write a lifestyle book that is to empower people to take control of their health and not cover sleep? You know, I can't do it. I just can't do it. What's so interesting about that is, you know, you had, you know, all of this time at medical school in practice, you know, and it took a conference.

Yeah. You know, that you, you know, through your own sheer interest and desire to try and help. My own money, my own sort of annual leave to go and do this stuff because I'm interested. That's where you got your sleep education. You know, that strikes me as so, you know, unfortunate. You know, I want to think, I want to work with medical systems to try and increase, you know, a sleep education component. Because wouldn't it be wonderful if all of our primary care physicians here in the United

Kingdom were, you know, as sleep aware and sleep motivated as you are? And I'm sure they would be delighted to receive that information. You know, I have lots of friends here who are doctors. And, you know, I know that they would embrace that and would love to try and increase wellness in their patients. But there's just no pathway that we've engineered in the medical system to gift them with that knowledge and dispense wellness to their patients. Because sleep really is the tide that raises all of the other health boats. It's just, as you said, it's the superordinate node that if you manipulate it, you know, it's like the Archimedes lever. You pull that, everything else, you know, can start to come into play.

Yeah, you get the sleep better. It affects your brain. It affects your hormones. It affects your genetic expression. It affects all these sort of things that we might be looking for drugs to affect those individual pathways. But you can improve a lot of them by improving your sleep. Yeah, and we think, well, that sounds almost too good. But don't forget, it took Mother Nature 3.6 million years to evolve this necessity of eight hours of sleep in place,

which I should note, by the way, that if you look at the data back in the 1940s, the average adult was sleeping about 7.9 hours of sleep. Now that number here in the United Kingdom is closer to six hours and 30 minutes. In other words, within the space of 100 years, which is a blink of an evolutionary eye, we've lopped off almost 20% of our sleep need. You know, how could that not come with demonstrable health and disease consequence? So I think, you know, there's that component there, but I love what you were saying that, you know, in medicine, we're often, or even in research and pharmaceuticals, we're often trying to sort of manipulate one pathway in one area of the metabolic system or one aspect of the immune system or one feature of the cardiovascular system. And, you know, sleep affects all of those.

And we can, you know, I'll give you an example. Firstly, we know that after if you get a patient and you have them sleeping just six hours for one week, this is someone, let's say, who is healthy. hours for one week. This is someone, let's say, who is healthy. At the end of that one week of short sleep, their blood sugar levels are disrupted so significantly that they would be pre-diabetic, that you would diagnose them as being in a state of pre-diabetic. Just from sleep deprivation. Just from sleep deprivation. You control all of the factors. You can also speak about sleep loss and the cardiovascular system. And all it takes is one hour of lost sleep because 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. And it turns out that when you look at that data in the spring,

when we lose an hour of sleep, we see a subsequent 24% increase in heart attacks as a result. It's just incredible, isn't it? But in the autumn, when we gain an hour of sleep, we see a 21% reduction in heart attacks. So the data's there on a global level, isn't it? Just from that. It's striking. And you can even think, you speak a lot about the immune system.

It's so key for our health. So tell us, what does sleep do for the immune system? So firstly, we can look on both sides of the coin. What happens when we don't get enough sleep? Firstly, we know that people who are sleeping five hours a night are four times more likely to catch a cold than those people who are sleeping eight hours or more. Striking study, very well controlled study. We also know that it doesn't take one week of, you know, short sleep deprivation. One night is enough.

What we've found is that if you take healthy individuals and then we limit them to just four hours of sleep for one single night, what we see is a 70% drop in critical anti-cancer fighting immune cells called natural killer cells, which are these wonderful sort of immune assassins that help decrease our cancer risk. Yeah, and help us fight infections. And fight infection. Part of our innate immune system. Exactly. Part of that critical innate immune response flipped the side of the coin.

And now what we find is that when you get sleep, there is a change in what we call the autonomic nervous system, which is sort of this automatic part of our nervous system. And that automatic nervous system is split into two branches. One that is sort of like the accelerator pedal that gets us revved up, triggers the fight or flight response. The other is the brake that sort of calms us down. And when we go into deep sleep, we apply that break to the nervous system and everything quiets down. Heart rate decreases. Deep sleep is the most wonderful form of natural blood pressure medication that you could ever wish for.

But one of the other things is that we see as that nervous system quiets down, levels of things like cortisol drop down, that stress-related chemical. levels of things like cortisol drop down, that stress-related chemical. And it's during that time that the body goes into an immune stimulation mode. And it's where essentially you're going to restock the armament of your immune army so that when you wake up the next day, you can battle and fight infection. What's also fascinating, and I love this data, infection. What's also fascinating, and I love this data, and this tells you just how critical sleep is to a fighting for our health. If you look at people who become infected or you actually infect them in the experimental laboratory, let's say with sort of a cold vaccine, you immediately trigger increased sleepiness and increased amounts of deep sleep.

And it turns out that the infection indicates to the immune system that you're under attack and the immune system will actually signal to the sleep system within the brain, we need more sleep. Sleep is the best battle force that we have right now to combat this assault. And so that's why when you're sick, all you tend to want to do is just curl up in bed and go to sleep. The reason is because your body is trying to sleep you well. It's an appropriate response to what's going on. Exactly. Our bodies are pretty clever, right?

They are remarkably clever. You know, again, Mother Nature has figured this out. And so she brings up this thing called sleep, which I would argue is probably like the Swiss Army knife of health. You know, whatever ailment you are facing, it is more than likely that sleep has a tool in the box to try and help fight it. That's so key. Whatever ailment you're facing, guys, if you're listening to this, whatever you're suffering from, whether it's a lack of energy on a day-to-day basis, or whether it's that you're worried about your risk of developing a chronic disease such as type 2 diabetes or heart problems as you get older, what Matthew is saying, what Professor Walker is saying is that sleep, improving your quality of sleep is going to help you with all these different facets. It's

going to help reduce your risk. It's going to help increase your energy. It's also going to reduce your risk of actually getting disease in the future, which is just absolutely incredible. I mean, we are going to move on to tips because I know many of you will be thinking, okay, this is all great. I'm sort of hearing about all these things that sleep does, but how do I get more? So we're going to come to that shortly, but so much I want to talk to you about, great, I'm sort of hearing about all these things that sleep does, but how do I get more? So we're going to come to that shortly. But so much I want to talk to you about, Matthew. I mean, I think we could easily make this like a full day podcast. I'm that fascinated in this.

I'd love to return at some point, should you wish me to. Yeah, well, 100%. But I think what you said about medical school training, I think it's very important because pretty much everything that I put in here, and then the last quarter of the book is on sleep. I'm not convinced that any of that came from my medical school training. So that was all self-taught from, you know, spending hours on PubMed, reading research, going to conferences, trying to learn more because I wanted to help my patients more. I thought, you know, I need to know more about this so I can actually do my patients, you know,

and give them a better service. So you're saying that, you know, maybe medical students may get maybe two hours or so. And you'd love to sort of try and help that and get, you know, maybe a sleep curriculum into medical schools. And this really, you know, I think one of the reasons we get on so well

is there's so much synergy in our viewpoint in terms of how we think this needs to change. So what I've done over the past six months is develop a brand new course with a colleague of mine, Dr. Panjshir, called Prescribing Lifestyle Medicine. And it's a one-day masterclass to teach healthcare professionals, but primarily doctors, on the basics of, you know, lifestyle medicine, if you will, as a term. on the basics of lifestyle medicine, if you will, as a term. So we go into sleep and we teach this framework where they can simply apply these four pillars with their patients. One thing that we do talk about on that course, and I think we've not spoken about this yet,

is about sleep and its role in mental health. And what's interesting, you mentioned bi-directional relationships before, and how a lack of sleep can increase our risk of problems, but also sleep can be a treatment as well for various things. And I wonder if you could talk about that in relation to mental health problems, such as anxiety and depression, and maybe from there, and just move briefly onto Alzheimer's if possible. Yeah. So we've done a lot of work in this area of sort of sleep and mental health. I think the first point to note is that we have not been able to discover a single psychiatric condition in which sleep is normal.

Wow. And I think sleep has a profound story to tell in our understanding, in our treatment, maybe even ultimately at some point our prevention of grave mental illness. And I don't say that flippantly. Firstly, we've done some work where you can take healthy individuals and you can deprive them of sleep for a single night. And then you place them inside an MRI scanner and you look at how their brain has changed. And what we find is that these deep emotional brain centers erupt when you're sleep deprived. You become a lot more emotionally reactive, impulsive.

There's a deep brain center called the amygdala, which is one of the centerpiece regions for the generation of strong emotions. That part of the brain is up to 60% more reactive when you're sleep deprived relative to when you've had a good solid night of sleep. And we've also found out- That's a huge amount, right? It's a 60%. It's very difficult to usually see that type of a change in the brain without

some kind of pathology or drug. Sleep deprivation will do it. On an intuitive level, most people recognize that when they haven't slept well, they're just a little bit more reactive to things that that email from a boss from their boss for example can be easily misinterpreted you know they annoyed at me they you know you suddenly start to see things that aren't there and i i've just i mentioned this before i've just completed my second book called the stress solution which is going to come out in january and i cover a little bit of this that you're talking about in that to really try and show people that, you know, lack of sleep is a stress on our body. And 60 percent, that's incredible.

Change in the brain, yeah. And I think it really comes, you know, you're absolutely right. Many of us have a sense that, you know, I just snapped, dot, dot, dot. You know, those are the words that usually follow a bad night of sleep or when you've not got enough sleep. And we know it all the way down sort of the age chain. You think about a parent holding a child, the child is crying and they look at you and they say, well, they just didn't sleep well last night. As if there's some universal knowledge that bad sleep the night before equals bad mood and emotional reactivity

the next day. And it doesn't stop in infancy or childhood or adolescence. It's true when we are adults as well. And we've seen this data. What I think is concerning is that that neurological signature that we discovered in that study is not dissimilar to numerous psychiatric conditions. And in fact, we're now finding significant links between sleep disruption and depression, disruption and depression, anxiety, including PTSD, schizophrenia, and most recently and tragically, suicide as well. In fact, a short sleep duration is usually predictive of either suicidal ideation, suicidal thoughts, suicide attempts, and tragically, suicide completion. So I think the scope through which sleep is impacting mental health disease,

I think is considerable. We used to think in psychiatry that the psychiatric disease was perhaps causing the sleep disruption. I think now we've been forced to change our minds. It's not as though it's completely in the opposite direction. It's not that every psychiatric condition is a sleep disorder. That's not true either. But is it a two-way street? I think that that's probably more tenable. In fact, is the dominant flow of traffic perhaps more in one direction than the other? I think that's also reasonable to assume on the basis of the data right now as well. So I think there's clearly an intimate relationship between our mental health and our sleep health. Matthew, the implications of what you just said, I think, are so profound. We've got to accept in

the 21st century, not only do we not prioritise sleep enough, we're a chronically sleep deprived society. We're now going through a mental health epidemic. You know, Mind, the charity here in the UK, say that about one in four people in the UK now in any given year are going to be diagnosed with a mental health problem. That's incredible. And when you hear about that research, we think chronically superposed society, mental health problems on the rise,

yes, there are other factors. Okay? I don't think i don't think you both of us agree on that we're not trying to say it's all to do with sleep but what we are trying to say is that sleep is a critical part of the equation and one that we can no longer afford to ignore um so i find that research fascinating you know and it makes me think as a doctor you know you've mentioned already type 2 diabetes heart disease mental health problems such as depression and anxiety you know i know at our previous discussion again guys i'd point you to that facebook discussion

we won't have time to go into this today but we will want to get you back on the podcast um on our facebook discussion we did go into al's and how, you know, sleep deprivation you feel may be causative now, or one of the causative factors that causes Alzheimer's disease. I'm thinking, well, you know, I often say this when I'm teaching doctors, you know, why are we not bringing up sleep quality with pretty much every single patient that walks in through our door? with pretty much every single patient that walks in through our door. And you could imagine the cost savings to our economy. In fact, the Rand Corporation recently did a survey,

the enormous cost of sleep deprivation throughout a number of developed nations. What they found was that a lack of sleep costs most nations about 2% of their GDP. So here in the United Kingdom, that's £ billion pounds of lost economic value caused by insufficient sleep. In the United States, it was $411 billion. In Japan, it was $138 billion. In other words, if you solve the sleep loss epidemic, you know, imagine you could almost double the budget for education, or you could perhaps even half the healthcare deficit. You know, Theresa May just this week, as we're speaking here, the prime minister of the United Kingdom, described a 20 billion pound injection of funds into the national healthcare system. And there's uproar about where that money is going to come from. Well, you know, if we just

simply prioritized and solved the sleep epidemic, the sleep loss epidemic, we could cover that and still have £10 billion left over. Yeah, I know. And you know, this podcast doesn't sound to be too political, but I would say that, you know, I find a lot of the messaging around the NHS and public very short-sighted. It's about pumping more money in to fix downstream issues, whereas we've got to look at prioritising sleep as a society, whether it's the lighting that's used in hospitals when patients are trying to recover from illness, which isn't very helpful a lot of the time, whether it's teaching our children about it and encouraging good habits at school,

but also as parents with our kids, really ingraining. And I think we've not really got into technology today and how the overuse of technology can potentially be problematic for sleep. I agree, sleep, it's such a simple lever to turn. It's also, well, we'll come into tips in just a second, but so many health inequalities are there from people from different socioeconomic groups. We know in the UK that you can have as much of a 10-year difference in your life expectancy depending on where you live. One thing I like about a focus on sleep, and I appreciate that there are many pressures in

deprived communities, financial stresses, maybe a lot of shift work, maybe working multiple jobs. So I absolutely understand and recognize that there are significant issues that we have to overcome. But a lot of the recommendations that we're now going to talk about that I cover in my book and you cover in detail in your book, most of the recommendations to help people to get more quality sleep are free of charge. Yeah. I often say that I think sleep is perhaps the most democratically freely available healthcare system for everyone around the world. Now, that's a bit of a glib statement on the basis of exactly what you just said, I think about, and the data is quite frightening. We've been looking at this too, at sort of low socioeconomic status communities. And there, what you'd see is just what you described,

you know, higher general social stress that impairs sleep, usually working multiple different jobs, split shifts, working the night work. Often people in those communities are working in the service industry. That usually means that you're either up very early or you're staying in work very late, all of which comprise, you know, factors that work against sleep. So I want to be really appreciative of that. But still, I think, you know, the tips that we can do right now to start sleeping better every night should be applicable and for the most part utilized by just about everyone, as long as you don't have a sleep disorder. and for the most part, utilized by just about everyone, as long as you don't have a sleep disorder.

Well, Matthew, normally I end the podcast off by asking people for four key tips that people can put into practice immediately, but we don't have to limit it to four. You know, I want this podcast to inspire people to not only take sleep seriously, but to give them some practical help. So immediately after listening to this, I can put the headphones down and go, right, I'm going to do what Professor Walker's asked me to

do. I'm going to try these five things today. In your experience, and you've been interviewed all around the world now to do with your book, what are those common things that people aren't doing that they could do to help improve their sleep? improve their sleep. Before we get back to this week's episode, I just wanted to let you know that I am doing my very first national UK theatre tour. I am planning a really special evening where I share how you can break free from the habits that are holding you back and make meaningful changes in your life that truly last. It is called the Thrive Tour. Be the architect of your health and happiness. So many people tell me that health feels really complicated, but it really doesn't need to be. In my live event,

I'm going to simplify health and together we're going to learn the skill of happiness, the secrets to optimal health, how to break free from the habits that are holding you back in your life. And I'm going to teach you how to make changes that actually last. Sound good? All you have to do is go to drchatterjee.com forward slash tour. I can't wait to see you there. This episode is also brought to you by the Three Question Journal, the journal that I designed and created in partnership with Intelligent Change. Now, journaling is something that I've been recommending to my patients for years. It can help improve sleep, lead to better decision making and reduce symptoms of anxiety and depression. of anxiety and depression. It's also been shown to decrease emotional stress,

make it easier to turn new behaviours into long-term habits, and improve our relationships. There are, of course, many different ways to journal, and as with most things, it's important that you find the method that works best for you. One method that you may want to consider is the one that I outline in the three question journal. In it, you will find a really simple and structured way of answering the three most

impactful questions I believe that we can all ask ourselves every morning and every evening. Answering these questions will take you less than five minutes, but the practice of answering them regularly will be transformative. Since the journal was published in January, I have received hundreds of messages from people telling me how much it has helped them and how much more in control of their lives they now feel. Now, if you already have a journal or you don't actually want to buy a journal, that is completely fine. I go through in detail all of the questions within the three question journal completely free on episode 413 of this podcast.

But if you are keen to check it out, all you have to do is go to drchatterjee.com forward slash journal or click on the link in your podcast app. Yeah, so there's probably maybe five things that people can do right now to get better sleep. The first is regularity. Going to bed at the same time and waking up at the same time, no matter what. Even if you've had a bad night of sleep, still try to wake up at the same time. Just understand it's going to be a tough next day. And then get to bed at the same time that following night, and you'll have a good night of

sleep. You'll sort of sleep a little bit more soundly that night. Even if it's the weekday or the weekend, don't do what we call social jet lag, which is sort of where you sort of sleep too late at the weekend. And then on Sunday night, you've got to drag your body clock all the way back and try and force it to sleep at a time when you haven't been sleeping before. That's torture. Regularity is key. The second thing is temperature. We've spoken a little bit about that, but keep your bedroom cool and probably around about 18 degrees Celsius, which is colder than most people think. But cooling the room down takes your body into that right sort of thermal space for good sleep. It cools it down. Darkness we've spoken about too, but we are, I think, a dark deprived society in

this modern era. And you need darkness at night to allow the release of a hormone called melatonin, which helps time the healthy onset of your sleep. So yes, it's to do with blue light sort of emitting devices, screens, phones. Those are things that you should try and stay away from in the last hour before bed. But it's not just that. It's also overhead lighting. You know, we don't need to be bathed in electric light all night. In the last hour before bed, just try turning half of the lights off in your flat or in your home. You'd be surprised at

how soporific and sleepy you become when you're shrouded in darkness. So that's the third thing. The fourth thing is, I would say, walk it out. And what I mean by that is don't stay in bed if you've been awake for 20 or 25 minutes, either trying to fall asleep or you've woken up and you're trying to get back to sleep. The reason is because your brain is this wonderfully associative device, and it will start to very quickly learn that being in bed is about being awake rather than asleep. So what you need to do is after about 25 minutes, just relax, understand that sleep is not quite here yet. Go to a different room in dim light, read a book or listen to a podcast.

But don't check email. Don't eat because it trains your brain to expect that in the middle of the night. Only return to bed when you are very sleepy. And that way your brain will start to relearn the association that your bedroom is the place of sleep rather than the place i think it's a really important tip matthew that you know i know even from our first conversation on facebook but you know whenever i talk about sleep you know people can often get really wound up about this and say you know i'm doing all those things i i can't sleep and they've you And they've really just, without trying to,

their brain has just got into this position where it's been trained not to sleep. It's been trained to not associate the bedroom with sleep. Or so many people I see, when I hear about on social media, are doing work emails right up to the moment they fall asleep. And we mentioned children before, and I often say, children need a bedtime routine. We know that.

Why as adults do we think we're any different? We should, and you're absolutely right. You know, we've turned the bed in this day and age often, you know, into a kitchen. We've turned it into an office. We've turned it into a cinema. You know, we do all of these things typically on the bed, which then it does impact the

brain's association. It gets quite confused about what this thing called the bed is all about. So I think that that's a very helpful tip. And try not to get too anxious if you're sort of falling asleep. I know that probably a lot of what I've been telling people will make you feel anxious if you're not being able to get the sleep that you need. But try not to worry about it. Everyone has a bad night of sleep. Just get up, understand that you're going to be awake for a little bit longer, and then go back to bed and you will start to relearn that association. And in fact, a lot of, you know,

people and patients will say to me, well, you know, I've been falling asleep on the settee watching television. And then I get into bed and I'm wide awake and I don't know why. And again, it's because of this association that you've learned with the bed. The final two things, one of which we've mentioned, is what you intake into your body, caffeine and alcohol. We've spoken about caffeine, but I'll speak about alcohol quickly. Many people use alcohol as a sleep aid and it is anything but an assistant to sleep. Alcohol is a class of drugs that we call the sedatives

and sedation is not sleep, unfortunately. Sedation is not sleep. It's very different. So what you're doing when you have a nightcap or you use alcohol to try and get to sleep, and many people do understandably so, they mistake one for the other. You're just knocking your cortex out. You're not in natural sleep. The two other problems with alcohol and sleep, firstly, alcohol will fragment your sleep. So if I were to record someone's sleep

in the laboratory after they've had a couple of drinks, their sleep is littered with all of these awakenings throughout the night. Now, you tend not to remember waking up, but the next day you feel again unrefreshed. You don't feel sort of bright and alert or restored by your sleep, but you don't remember waking up. So you don't link it to the alcohol, but alcohol is bad at fragmenting your sleep, produces poor quality. The final thing alcohol is good at doing is blocking your dream sleep or your REM sleep. And we know to come back to our conversation, REM sleep is critical for emotional first aid. REM sleep provides overnight therapy. It's a form of emotional convalescence and alcohol will block that

REM sleep quite viciously. So those would be the five tips I think for better sleep. Yeah, Matthew, thanks. I love that. Just to say on alcohol is it dose dependent? So for example you know some people say well I'm okay with one glass of wine but two or three glasses is going to fragment my sleep. You know can you comment on the dosage there or would you advise people who are struggling with sleep to knock it on its head basically? I know and it's so hard for me to answer this. And this is one of the many reasons why I'm such a deeply unpopular person. I don't think that's fair to say.

But, you know, firstly, I don't want to sound puritanical. You know, life is to be lived to a degree. And all of these things that we're discussing, we're trying to speak about the extremes. But I also want to empower people with the knowledge. I'm not here to tell you necessarily what you should or you shouldn't do. I just want to give you the scientific facts and then you can make the choice. I would say, unfortunately, that even just one glass of alcohol in the evening, we can see that, we can measure that. You can measure that. In your lab,

you can see that you're not getting the same deep level of restorative sleep even with one drink even with one drink so i know it's hard but now you know everyone you know should you know have a social life and sort of you know enjoy a drink now and again i think the best advice would be this if you're going to bed feeling tipsy you probably have had too much alcohol in terms of sleep impairment well i i think you know i i so resonate with it with so much of what you've just said, which is, you know, this podcast, what I do, what you do, it's not about telling people what to do. You know, I've got no interest of telling someone what they should do.

I have no right to tell someone what they should do with their lives. What I think we're trying to do is to educate people, inspire them, empower them to understand what lifestyle choices they're making and how that could impact their health. And I always draw the analogy with going out, how many of you drinks with your mates on a Friday night? People know intuitively that if I go out for a drink on a Friday night and have three or four pints, let's say, you know what, my Saturday morning might be a bit of a write-off. I may not be functioning as well as I might want to. But you're going into that with that knowledge. You're saying, you know, I know the effect alcohol has on me, but I'm going to get so much enjoyment out of my night out tonight that I'm willing to

put up with the consequences. What I think we're both trying to say is, guys, we just want to empower you. We want to help you understand the impact that caffeine might be having on your sleep, that alcohol might be having on your sleep, that the fact that you're on your work emails before you go to bed might be having on your sleep. Do with that information what you will, you know. That's how I would put it.

I so agree because I think, you know, a lot of what you speak about in your book, which is, you know, far more wide ranging than mine, because I just take one of the things you go after four of the key pillars, which is so much more impressive. I think it says so much about the difference between me and you, Rangan. Well, you're a recent, I'm a clinician, right? There's a big difference, right? There is, but I still think it's a heroic thing. There is, but I still think it's a heroic thing. But what I would say, I think, is that, yes, a lot of people are aware of some of these things. You know, like it's good to be physically active. You know, I should try and stay away from drinking too much alcohol. But I also think that there's a lot of what we discuss, you know, I hope in both books, that is perhaps knowledge that people aren't aware of. And if only that they were aware of it, they would actually want to do something different. That's the sort of the case that I'm really passionate about is that people, as long as you know the information

and you choose to do otherwise, no problem at all. A lot of people just are either misinformed or entirely when it comes to sleep, uninformed. That's the goal. That is the goal. And it's really about, it's that empowerment piece and and this is one thing i just want to end on is just to say guys look it may not be that you can just change one thing and suddenly have a great night's sleep you might have to change three or four things together you know that's certainly my experience it's like you

know matthew you know you're a researcher so a lot you know you'll do research and showing what caffeine does on showing what alcohol does. But I would say as a clinician, use that research, but maybe you might have to try a few things. You might try, for example, one week with no caffeine and no alcohol and see how you sleep, because then you can be empowered to decide what are you going to do after that. Are you going to go back? Or maybe then, I always try and get people sleeping as well as they've ever slept.

Then they can start reintroducing some of these lifestyle things that they want and they can say, oh, wow, that's interesting. I felt great last week, but now when I have a 2 p.m. coffee, you know what, I'm not quite as good. Okay, that's going to teach me now that I'm going to knock it a bit earlier in the day because I think ultimately nobody's going to follow your advice or my advice simply because we told them to.

I think it's only when they start to feel the difference themselves, they go, wow, you know, I kind of like feeling good. Yeah, and I think, you know, I love your point about just trying to give it time too. You know, sleep and starting to change your sleep and seeing the effects of getting better sleep. It's a little bit like exercise at the gym. You know, you're not going to go to the gym one day and wake up looking like Arnold Schwarzenegger. You know, it just takes some time. But if you commit to it, you will see gradual change. And it's the same thing with sleep as well. But I also think I love the idea of you putting sleep in that bedrock place and then starting to introduce the other factors.

What's lovely is that many of them will actually fall in place when sleep is stabilized. And I'll give you a good example of diet. We know that without sufficient sleep, two critical appetite hormones go in opposite bad directions. appetite hormones go in opposite bad directions. One of those hormones is called leptin, which is a hormone that sort of signals to your body, you're full, you don't want to eat anymore. The other hormone is called ghrelin, which does the opposite. It says you're not satisfied with your food, you want to eat more. And despite leptin and ghrelin sounding like two hobbits, they are actually real hormones. What's interesting is that when you sleep deprive people or even just limit them to maybe just like five or six hours of sleep for a week,

levels of leptin, which say you're full, don't eat more, they drop down. Levels of ghrelin that ramp up your hunger and say, I've just eaten a big meal, but I'm not satisfied. I want to eat more. That hormone skyrockets when you're underslept. So no wonder people who are sleeping just five to six hours a night will actually eat on average somewhere between 200 to 300 extra calories every single day. So you can solve sleep and you will actually start to not want to eat as much. And this is why a part of weight loss is to sleep better. It's a critical factor.

And I think next time I get you on, Matthew, we'll probably go into detail on that. We'll probably go into detail on Alzheimer's and maybe even things like menopausal symptoms and hormonal symptoms. I also see sleep deprivation playing a huge role in. I know you're on a really busy schedule. That's how it is when you have such a popular

international bestselling book. And you know all about that too. Well, guys, I'd highly encourage you to pick up Matthew's book, Why We Sleep. It's absolutely brilliant. It's got pretty much everything you've ever wanted to know about sleep. I think you'll probably find in that book. I look forward to when you release a later edition, when you've got newer research coming out in the future at some point. But Matthew, one question I like to ask my guests who are leading researchers in the field is, as you became more

and more aware of all this sleep research, what was the biggest thing in your own lifestyle that you changed on the back of your research? I think it was probably caffeine. I think just seeing the data and then doing those types of studies ourselves, and particularly the finding that we discussed were even if you're asleep, the quality of that sleep is just not as deep. That really got me concerned, and that's when I really started to pay attention to my caffeine content. Are you teeter-totter now with caffeine?

So right now, yeah, I am. I drink decaffeinated tea and I drink decaffeinated coffee. I sometimes, you know, I've ebbed and flowed between sort of having coffee in the morning because I do feel it's alerting benefits. But, you know, we didn't necessarily evolve to be medicated with caffeine. And I think anyone who's, you know, drinking caffeine at 11 a.m., which on the basis of your circadian rhythm, if you listen to the wonderful podcast with Sachin Panda that you did, you know, your peak of your circadian rhythm is right around sort of the 11 o'clock period. That's when it should be almost impossible for you to fall asleep. But yet, you know, I sometimes look around on an airplane when I'm leaving and people, half the plane is asleep at 11 o'clock. And if you're self-medicating your sleep deprivation at 11am with caffeine, it usually means that you're perhaps just not getting enough sleep. And

that's probably been one of the greatest, I think, influential factors. That and the impact on my productivity, I think that was the most underrated. And it actually forced me to start doing a lot of research on sleep loss and productivity that maybe on a second podcast we can talk about. What we can get into, yeah. But, you know, my ability to maintain focus and produce high quality output work is dramatically dependent on the sleep that I've been having at night. Really hope you enjoyed that conversation. As always, do think about one thing that you can

take away and start applying into your own life. Matthew did come back on the show for a part two, that is episode 147. So if you enjoyed my first chat with Matthew, do go back and listen to that episode when you get a moment. Thank you so much for listening. Have a wonderful week. And always remember, you are the architects of your own health. Making lifestyle changes always worth it. Because when you feel better, you live more. Thank you.