Feel Better, Live More with Dr Rangan Chatterjee - #194 BITESIZE | Why Sleep Matters (and How to Get More) | Matthew Walker

Episode Date: June 24, 2021

We often think of sleep as the third pillar of health underneath diet and exercise, but Matthew believes sleep is the first pillar on which all others sit. Feel Better Live More Bitesize is my weekly podcast for your mind, body, and heart. Each week I’ll be featuring inspirational stories and practical tips from some of my former guests. Today’s guest is world-leading sleep researcher, author of the international best-selling book ‘Why We Sleep’ and Professor of Neuroscience and Psychology, Matthew Walker. Matthew shares research on how important sleep is for our health and the amazing power it has to recharge our mind and body. We explore how proper sleep can benefit your life and Matthew shares his tips for better sleep. Show notes and the full podcast are available at https://drchatterjee.com/26 Thanks to our sponsor http://www.athleticgreens.com/livemore Follow me on https://www.instagram.com/drchatterjee   Follow me on https://www.facebook.com/DrChatterjee   Follow me on https://twitter.com/drchatterjeeuk 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 other qualified health care provider with any questions you may 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. 

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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. Welcome to Feel Better Live More. Bite size your weekly dose of positivity and optimism to get you ready for the weekend. Today's clip is from episode 26 of the podcast with world leading sleep researcher and professor of neuroscience and psychology, Matthew Walker. In this clip, Matthew shares research on the importance of sleep for our overall health and the amazing power it has to recharge our mind and body. You make a very powerful case why sleep is the foundational pillar of health.

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 and I'll give 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. We know that without sufficient sleep, two critical 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 two to 300 extra calories every single day. Yeah. So you can solve sleep and you will actually start to not want to eat as much. 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. 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. But physical activity is a great way to enhance both the quality and the quantity of your deep sleep. 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? Sleep really is the tide that raises all of the other health boats. It's the superordinate node that if you manipulate it, it's like the Archimedes lever. You pull that, everything else can start to come into play.

You get the sleep, but 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, you know, and it's no, we think, well, that sounds almost too good, but don't forget, you know, 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 6 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. need. 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 you speak a lot about, you know, 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, you know, help decrease our, you know, sort of, you know, 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. Flip the sort of 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. 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, 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. That's an appropriate response to what's going on, right? 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 listen 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. In your experience, what are those common things that people aren't doing that they could do to help improve their 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. Keep your bedroom cool. 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. 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. 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. 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. Yeah, Matthew, thanks. I love that. Let's go into caffeine. I mean, how much of a sleep disruptor is caffeine? 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. You know, 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 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 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 you're going to do after that. 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 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 that's

gonna teach me now that i'm gonna i'm gonna knock it a bit earlier in the day because i think ultimately nobody's gonna 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. Hope you enjoyed that bite-sized clip. Please do spread the love by sharing this episode with your friends and family. And if you want more, why not go back and listen to the full conversation with my guest. And if you enjoyed this episode,

I think you will really enjoy my new bite-sized Friday email. It's called the Friday Five. And each week I share things that I do not share on social media. It contains five short doses of positivity, articles or books that I'm reading, quotes that I'm thinking about, exciting research I've come across and so much more. I really think you're going to love it. The goal is for it to be a small yet powerful dose of feel

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