ZOE Science & Nutrition - Michael Mosley: 4 habits that changed his life

Episode Date: March 16, 2023

If you had to do just one thing to improve your health, what would it be? Our busy lives mean it can be difficult to keep up healthy habits, and with so much conflicting advice out there it’s tricky to separate fact from fiction. In today’s episode, Jonathan is joined by medical doctor, journalist, and presenter Michael Mosley, who is alongside ZOE regular Tim Spector, to discuss Michael’s four key habits to improve our health.  Michael’s latest book ‘Just One Thing’ explores these habits and has seen him speak to singing scientists and eccentric iceman to healthy habit experts and evangelists. And of course, being Michael, he tried every habit out himself. We talk about which methods are the most effective, which he has incorporated into his life, and how he makes his new habits stick. Download our FREE guide — Top 10 Tips to Live Healthier: https://zoe.com/freeguide Timecodes: 00:00 Introduction 00:12 Topic introduction 01:38 Quick Fire Questions 03:24 Michael's simple changes to improve health 04:26 Are cold showers good for you? 05:54 How long do you need to be immersed in cold water for the benefits to work? 06:40 Can cold showers improve mental wellbeing? 10:25 Potential dangers of cold water swimming 11:58 Do cultural differences present different outcomes across the world? 13:08 Can these small stressors help us? 13:28 What is the theory behind this working? 15:21 Will this work for everyone or is this very personalized? 17:45 What effects does breathing have on your health? 18:57 How breathing exercises affect our brain 21:23 How do you keep up the breathing exercises? 22:36 ZOE app breathing exercise 24:44 Is there a difference between breathing through your nose and your mouth? 26:04 How important are plants and nature for our health? 29:21 Can exposure to nature improve things like mental health and even gut health? 31:01 Can herbs also help improve our health? 31:27 What are the benefits of exercise? 32:42 What are endocannabinoids? 33:41 Are preferences for exercise genetic? 35:12 Is it endorphins that make us feel good after / during exercise? 36:31 How exercise affects us is extremely personalized 38:42 How do we encourage people who don't enjoy exercise to do it? 40:13 Tips to improve your exercise routines 43:08 Are there benefits to walking downhill? 45:42 Summary 48:34 Goodbyes 49:08 Outro Episode transcripts are available here Michael Mosley’s book is available to buy here Follow ZOE on Instagram: https://www.instagram.com/zoe/ Have an idea for a podcast? Contact Fascinate Productions to bring it to life.

Welcome to ZOE Science and Nutrition, where world-leading scientists explain how their research can improve your health. If you had to do just one thing to improve your health, what would it be? It's a question that medical doctor, journalist and presenter Michael Mosley set out to answer in his book, Just One Thing. From singing scientists to eccentric icemen, Michael spoke to healthy habit experts and evangelists to separate fact from fad. And of course, being Michael, he tried every habit out himself. What we wanted to know was, having tried them all, which are the most effective?

Which has he incorporated into his life? And how does he make his new habits stick? Today, Michael joins us alongside Zoe regular Tim Spector to discuss his four key habits to improve our health. Michael and Tim, thank you for joining me today. I feel surrounded by an amazing amount of knowledge on lifestyle and nutrition, and I'm really looking forward to this. We always start the podcast with a quick fire round of questions from our listeners, and the rules are very simple. You can say yes or no, or a maximum of a one sentence answer, but no more than that. And I want to have a little bit of fun this week because I think having Tim here with

you, Michael, I know that Tim is a bit of a rebel. He doesn't really like to agree with anybody. And so I thought it would be quite fun to ask each of these questions and have Michael first and then Tim afterwards and see where that leads us. So this might be a horrible idea, but I thought I would give it a go and I'm far enough away that Tim can't hit me. We can always edit it out if it ends in a bloodbath. All right. You both trained as medical doctors. For the average person, can lifestyle changes be as powerful as medicine for our health? Yes. Yes.

Easy, you see. All right. Can plants around us in the house or in the garden make us happier? I think they can make you feel happier, yes. Definitely nature makes you happier, yes. We've evolved to be happy in nature. Is a cold shower really good for our health? Perhaps. I think the science is still a little bit out on that one. I'd agree. I think it might vary enormously by individuals and it's something we really need to test. Can the way we breathe affect our mood? Yes.

I'd say perhaps. I'm glad. I was looking for a little bit of disagreement, and we'll talk a bit about this. I'm looking forward to talking about this one. And lastly, if we exercise regularly, will we start to enjoy it? No, not necessarily at least. Well, I know Michael doesn't enjoy it. That's why he said no, but I think it's highly personalized. So some people will, and I think there's definitely some people who won't. Brilliant. Well, look, I think that sort of sets up the podcast beautifully. And so, the idea we had, very lucky to have Michael and Tim on the podcast, is that Michael's investigated a lot of sort of new and emerging health trends over the years. And one of the things that he's been really focused on recently has been this idea of sort of simple changes. So,

something that's not too complicated that you could take on board that could actually have like a real impact on someone's health. And some of these ideas are quite surprising. Some are even really quite counterintuitive. So why would dumping a load of freezing water on your head be any good for your body? That sounds sort of mad. Or why would running down a hill potentially be better for you, for your muscles than running up a hill? And so we thought it would be fun to run through a few of these and understand a little bit from Michael and also from Tim about their views on, I guess, these emerging new ideas. And I thought the first one, since we've just sort of touched on it already, that would be fun to talk about is cold showers.

And Michael, do you want to explain, I guess, what you've seen and your thoughts about it? Yeah, so cold showers and also cold water swimming has become incredibly fashionable, though it has been around for a very, very long time. And the Romans used to practice having warm dips followed cold dips and things like that. So lots of enthusiasm for it. And as part of the sort of just one thing, I gave it a go and I have persisted with it. But a lot of hype around it as well. Wim Hof is a famous advocate of hanging around in your underpants in sort of sub-Arctic temperatures or dipping himself in barrels of cold water. And for a series I recently made

called How to Live to 101, I went to interview him in Holland and he did all these things with great gusto. But I think the science is not perhaps as firm as some of the advocates would say, but there is definitely something there and I'd love to see it explored more. But in brief, what I do these days is i go

and have my warm shower wash myself and then i blast it to cold and then i stay in there for about 40 seconds i normally sing vigorously while i'm in the shower but that detracts from the cold my wife also does it she allows the water to stoically fall over her um i spoke to a guy called mike tipton who is a professor at portsmouth university and who studied the effects of cold water immersion and he advised me that what you need to do is stay there long enough until you stop gasping because your first reaction to cold water immersion is and then you have to slow it down and And when your heart rate, and well, basically when you stop gasping, that probably means you've been there long enough. And you've been doing this for quite a long time then? This is a one thing that has stuck?

It has stuck, but it's more, to be honest, in the summer months than in the winter months. The winter is too cold, and I find it a bit brutal. And I sort of have swings and roundabouts. So the main two areas where cold showers do seem to have an impact, and particularly cold water swimming has an impact, is potentially on the immune system and secondly on your mental state, if you like, on happiness, on how you feel. So the data around the immune system is variable. That's what I could say. The best study so far was probably a Dutch study where they recruited 3,000 people and randomly allocated them

to either having a 30-second cold shower, a 90-second cold shower, or just sticking to a warm shower. And they had to do that for a couple of months. And then over the subsequent winter, they looked at how many people took time off. And the group who had had the cold showers, they took significantly less time off. Now, it didn't seem to matter whether it was 30 seconds or 90 seconds. They got the same sort of, you know, effect. So that's not a truly wonderful study, but it is at least indicative.

What do you think, Tim? Yeah, I mean, I haven't looked recently, but what I did a few years ago, a lot of these are case reports of people maybe with quite severe depression that do get benefits from this. I think the immune studies are always hard and there are confounders about, you know, things like time off. But I believe there's probably a strong placebo effect of these showers, which we shouldn't ignore, that is highly effective. And I started doing this just to see what it was like and what could I put up with it. And interestingly, it's the opposite. In the summer, my cold water system goes much colder than it does in winter, where it's heated up by the hot water. So I get more of a differential in summer. So I find in winter,

it's not much different, really, because I've got a really old heating system. But I did find it, yeah, sort of invigorating. So whether that boost psychologically helps you and then, you know, aided by a bit of placebo and the idea that people like Michael are saying it's good for you and Wim Hof. But I think it's going to be highly personal. And I think we do know from temperature regulation in the skin and things that there's huge genetic variations in how people respond to cold. And we did a lot of these twin studies, putting twins' hands in ice buckets and things, and found that this perception of that cold pain varies enormously between people.

And I think this probably means that these treatments need to be quite personalized. And 30 seconds cold showers for some people might be absolute torture. For other people, it's nothing at all. So I think we need to refine this much more. Definitely worth doing bigger population studies. And I think this is one of the things we'd love to do in the Zoe Health Study is get people taking cold showers. And I like the idea that you may only need 30 seconds

because I think most people could get away with that. Absolutely. And beyond that, I love the idea that it's not necessary to do more. The more is not better. What Professor Mike Tipton said to me is he thought it could be that what you're doing is you get a stress response. You get stressed when you have a cold shower, without a doubt. You do adapt. It takes about six sessions before you adapt and it becomes, for most people, more acceptable. But he said that it seems to be that you get a cross response so that he did a study where they got people to do cold showers and then

it turned out that they were better adapted to you know surviving at altitude that being you know responding to one thing was better than another thing so he thinks there may be something going on there he also stressed some of the dangers. And indeed, I was involved in a rather peculiar incident a couple of years ago. I was swimming in the sea with my wife, Claire, off the coast of Cornwall. It was May. It was pretty cold. And we'd just gone out to a boat and were swimming back. And I thought, I'm going to beat Claire to the shore. And the next thing I know, I'm in casualty. And apparently what had happened is I'd swam back to shore. Claire swam ashore as well. And she said, how are you, Michael? I'm looking really vacant. And I clearly have no idea who she is or who I am or where I am.

Though I kept on repeating, I have a wife, I have four children. And so I ended up in casualty and got a thorough examination, couldn't find anything. And then the consultant rolled up and he said, you have something called transient global amnesia, which is relatively rare, but it's brought on by swimming in cold water. So my memory banks have been entirely wiped for about two, three hours. And then it gradually came back. It's like a plot for a really bad sort of Spanish drama series if it only is supposed to last for three months and not three hours. So I think that's amazing this actually happened. It's a great excuse. Every morning you have a cold shower. You say, oh, I've got global amnesia. I can't remember.

Was I really supposed to do this podcast? Well, exactly. Was I supposed to be here or not? The other thing is apparently it's caused by a sort of transient change in your blood pressure and the blood flow to the brain. It can also be triggered by sex. The neurologist told me so that is also, you know, you have sex and then you completely forget who you are, where you are and who you're with. That, again, is kind of rare. But the serious point here is don't go cold water swimming by yourself, particularly if you're not used to it, because there are risks. Particularly if you're unfit, you could have a heart attack, drop dead. You could have your memory wiped.

Who knows? So try and do this sort of thing with someone else. And it's interesting. I have a personal story here. I have a very good friend who will know who he is when I mention this, who started working for a company that's based in Finland. So way off in the icy waste. And he went there for his first sort of company offsite about three weeks ago. And the entire company went and had a big sauna get incredibly hot on an island. And then

apparently they walked out onto the ice and they've dug a big hole and they expect everybody to just jump in. And apparently everybody who was finished was just, they didn't only just jump in the water. He said they sort of sat in the water having a pleasant conversation. And my friend thought about this quite hard and then said, no, I'm not going to do this. So clearly there's something cultural here also, isn't there, about thinking that this is normal. Or thinking this is insanely dangerous. Yeah. Or insanely dangerous. So what's our view?

Is this making everybody in Finland live longer, Tim? I'd like to share something exciting. Back in March 2022, we started this podcast to uncover how the latest research can help us live longer and healthier lives. We've spoken to leading scientists around the world doing amazing research. And across hundreds of hours of conversations, they've revealed key insights

that can help you to improve your health. If you don't have hundreds of hours to spare, no need to worry. At the request of many of you, our team has created a guide that contains 10 of the most impactful discoveries from the podcast that you can apply to your life. And you can get it for free. Simply go to zoe.com slash free guide, or click the link in the show notes. And do let me know what you think of it. Okay, back to the show. Well, they always claimed that saunas were helping people. But I think when they did some studies, they found there were as many people who had heart attacks as maybe lived longer. So it's probably highly personalised.

But I think the point is that if you're doing something regularly and small stresses to your body, generally that's a good thing. So as a general principle, a lot of the things I think Michael talks about are these small little mini stresses and this whole concept of hormesis, a little bit of what hurts you helps you, a little bit of poison is good for you. And can you explain that for a minute? Just because I think the story sounds great. I think the thing that I'm struggling with is why is doing something that is unpleasant, like a cold shower going to help? I think we understand with exercise that we understand that you're going to build your muscles, all these things,

but the cold shower I'm struggling with, why might that be good for us? I mean, the idea is, as I said, that you build resistance to this particular stressor and therefore potentially you are developing resistance to other stressors as well at the same time. There's also a thing called cold shock protein. When you're in hot water, there's heat shock protein and these things are associated with repair. As you're saying, with exercise, you damage yourself, you rip muscle and it's actually the process of repair which seems to be good for you. When you do something like fasting, then again, one of the arguments is the reason why it has been, at least in animals and in some human studies, been shown to prolong life is because

it is stressful. And stress evokes response from your body. As Tim said, that which does not kill you makes you stronger. It's all about getting the dose right if you did that it actually stimulates the whole system a little too much and it it knocks you off yeah a little spot of arsenic peps you up never hurt anybody that's right please don't try this at home is I think what we had immediately on the podcast but and it sounds like just just to summarize this is like's interesting. The scientific data isn't really strong is what I'm hearing. So this is one of many of these areas where there's something interesting. There probably hasn't been enough experiments done at enough scale to really show whether it's compelling. And I think also, Tim, your suspicion is there's a lot of personalization

in the sense that this might really work for some people and not for others? Yeah, absolutely. The dose might vary for different people as well. You know, as our immune system is highly variable and personalized, so we might need different stresses and things. So this is very much an overarching theory that it's very hard to do these experiments in humans. And, you know, stressing a worm and making it live longer isn't necessarily the same in humans. But generally, the age research community is coming around to these ideas that these things are important. And it's all about, you know, how our body senses these stresses

and these outside influences, whether it's diet or from the outside world, and then sends other repair mechanisms to sort of work. So it's definitely more of a hypothesis at the moment than actual hard fact, but it does seem to explain a lot of these anecdotal events. I've actually been making a series for the BBC called How to Live to 101, which took me around the planet. And I was looking at some really interesting stuff in Israel, where they induce a relative hypoxia. So what they do is they put you into this bariatric chamber, which basically, you know, can raise and lower air pressure. And then you have to inhale oxygen, they whack the pressure up, and then they drop it. And so your body perceives this,

you know, you're kind of short on oxygen. So you think that's a really, really bad thing. Your brain's going to go, oh, I'm going to oxygen. But actually what they've shown is that doing this leads to the production of BDNF, brain-derived neurotrophic factor in the brain, the release of more of this stuff. And they've got some pretty compelling evidence now indicating that it's helpful for things like stroke, possibly for long COVID. And they're doing big numbers. I mean, this was a large institute, lots of people, proper science going on. And you would not have bet money that inducing hypoxia was a good thing for your brain. And as I said, that's some of the, it's a different way of stressing your system. Again, not something you want to try at home. Well, that also links in with some of these breathing exercises that are coming along

where they're actually promoting increasing the CO2, carbon dioxide, in your blood. And that seems to be another stress that is helpful and actually helps you absorb more oxygen. So some of these things seem counterintuitive, but it's all on this general theme. It's a stress. Well, that's actually a brilliant transition because the next one that I wanted to talk about was taking deep breaths because that also seems a bit ridiculous as something that's going to make a difference to your health. It's something that I might sometimes say to my wife and my wife might sometimes say to me health. It's something that I might sometimes say to my wife, and my wife might sometimes say to me, but that's mainly because I was really annoying,

not because I think it's going to affect your health. But actually, I think, Michael, you had some really interesting stuff about this idea that actually the way we breathe might have some impact on our health. And I'd love you to sort of share what you discovered. Sure. So when I was looking into just one thing, I'd been sort of aware of it because my sister teaches mindfulness and kind of breathing is part of that, at least being aware of your breath, but not actually consciously controlling it. And then I came across this really interesting research

showing that deep belly breathing. So the idea is it's not just deep breathing or slow breathing. It is belly breathing. You're trying to, you put your hand on your gut and you should feel it kind of go up and down rather than breathing. You do really slow, deep breaths. And one technique is called 4-2-4.

There are quite a few other ones, but essentially you breathe in through your nose to a count of four, hold it for two, and then you breathe in through your nose to a count of four, hold it for two, and then you breathe out through your mouth to a count of four. And when you do that for even a minute or so, what happens is your heart rate will start to drop, and you'll kind of begin to feel calmer. And I was interviewing an expert, and he said one of the reasons is, as Tim was sort of alluding to, you're altering the carbon dioxide levels in your brain. This switches on part of your system known

as the parasympathetic system, which is releasing noradrenaline. So everything kind of calms down. And all the great religions have sort of advocated some form of breathing exercise. It's been particularly popular with people who are doing yoga and things like that. They've of advocated some form of breathing exercise. It's been particularly popular with people who are doing yoga and things like that. They've always advocated different forms of deep breathing. But now we're kind of recognising there's something really to it. And when we did a podcast on it, it was overwhelmingly the most popular podcast we had ever done. And that was just about breathing, which shows you, I guess, there are a lot of people out there who experience anxiety and sleeplessness, because I was essentially saying this is a really good way of coping

with an anxiety attack or if we're feeling anxious. But also it's something I do at three in the morning when I'm waking, you know, and lots of restless thoughts. I just practice this breathing and it's surprisingly powerful. That's really interesting. I was actually, because I read it, I thought that I I remember that I was taught breathing techniques in my early twenties. I was diagnosed with a lot of food intolerances as quite a few people listening to this podcast know, which sort of started my 25 year journey of Zoe. And when I went to see all the doctors, you know, you don't have

cancer, et cetera, that's good. They didn't even know what the microbiome was back then, Michael. So that definitely didn't come into the conversation. And so the conclusion was, probably you're really anxious and this is like a big part of this. And so I got sent to see somebody who taught me about breathing with some sort of feedback mechanism where you could sort of see something on the screen going up and down. And I think what I took away was you really could reduce your level of tension from breathing. And I was terrible at ever remembering to do it at any points when I really needed to use it. So I think like many of these things, there's this sort of huge gap between this healthy habit that you should do and then actually managing to do it. Is that a common challenge or is this just, am I the only person?

Oh, absolutely. But the thing is, you need to practice. You need to practice, practice so that when you are having an anxiety attack, a panic attack, when you're feeling terrible, you actually do it because your natural inclination is to hyperventilate. That when you're feeling anxious, you're like, and then you go, and then that makes you feel much, much worse. And you forget everything you've ever heard on some podcast or other.

And you just go. And that is having the reverse effect, is it? So it's the opposite of the deep breathing that you're describing. That's actually making you more anxious through this breathing. Yeah, you've got to kind of practice it. And as I said, you've got to find a technique that works for you. Another very simple one is four, six. So you breathe in for a count of four and then out to a count of six. And actually the exhale, some people say the exhale should be longer than the inhale, but you find something

you're comfortable with. You practice it. You take a few minutes out of the day to do it. You've got to find a trigger. So I find, for example, with things like doing press-ups and squats, I do them first in the morning. I do them with my wife, Claire. Two reasons. One is we encourage each other to do these exercises. Otherwise, you know, you probably wouldn't because the moment passes. And the other is I'm using the fact I've got to get out of bed as my trigger to do them. If you want to try and breathe like Michael, you can go on the Zoe Health Study app. And at the moment, we're running a study where we're trying to was three, four, five. So breathe in for three, hold it for four, then breathe out for five, which is this idea that actually you're slightly exhaling more and making yourself slightly hypoxic as a way of clearing out the system.

And hypoxic, Tim, hypoxic means? Hypoxic means you're getting low in in oxygen relatively so we always thought that was a bad thing and as michael says you know there are lots of treatments that seem to uh improve you by doing it again it's this sort of stress and studies have shown that if you do sort of get rid of oxygen which means you're by definition building up carbon dioxide in your in your body more than you would normally do this can have actual positive benefits and allows you there's some evidence in athletes that if you build up co2 then it allows you to use the oxygen better and actually it's become your your body becomes slightly more efficient so this is all done on small numbers, and we haven't really sort of worked out how this works at a population level. That's why we sort of want more people

to do these studies and say, well, who does it work for? You know, is it the same for men and women? Is it different at different ages? But the act that we developed and is still developing, it's still an evolving thing, helps people log every day how they feel and whether it's helping them or not. And I think, you know, we'll hopefully come back and we can discuss some of these results. But anyone who wants to go, they can still go on and download that app and have a go. And it's just another thing to think about in our busy lives, just say, am I actually breathing properly? Should I? Unless I've got a cold, why am I breathing through my mouth? You know, think about it. Absolutely. Interestingly, I've actually just been doing a podcast where we're looking at mouth

breathers. And as you say, if you breathe through your mouth, it kind of dries out your mouth. It makes you more prone to infections in the mouth, dental caries and things like that. And obviously you can snore more. But what was really interesting as I was talking to a Norwegian scientist, and he said, when you breathe through your nose, he discovered that breathing your nose releases nitric oxide in the nose. And this kills the bugs in the nose. But the nitric oxide also travels through your blood to your lungs. And that increases oxygenation, particularly in the upper lobes of the lung. So we don't entirely know what that means, but it's kind of interesting that there is a significant difference between being a mouth breather and a nose breather from that

point of view. And again, it's something that the yogics have been keen on for a while. Is yogic a word? I don't know. But yeah, it makes you kind of think even a simple thing like breathing can have quite a profound effect on your sort of mental and physical state. My grandfather in Australia, when I was six, took me out every night into the garden. He was in the Australian army and used to get me and my brother to do deep breathing exercises. We were in our pyjamas before going to bed and we thought he was completely mad. But of course, he was way ahead of his time then. That's brilliant. Well, I think going into the garden

is a brilliant transition to the next simple thing. And I would love to talk about houseplants and the benefits of gardening more widely. I'm quite a keen gardener myself, although I do find that Zoe has slightly restricted the amount of gardening that I might want to do, never mind having broken two toes. But I've never really thought that it had any real health benefits, but I believe, Michael, that there might be some suggestion that it does. Absolutely. I think Kai and Tim and you and everybody would agree

that spending time in green spaces is really good for you. And there's also research showing that spending time in blue spaces, which is down by the sea or by a river, is also kind of good for you. We were looking specifically at houseplants. Now, I was kind of critical, or at least a little bit cynical about this. But a couple of years ago, when I was making a series called Trust Me, I'm a Doctor, we did this experiment with the University of Lancaster, which I thought will never, never work, but the results were really interesting.

What we did is we were looking at the health of people living near a busy road and we got them to wear the pollution monitors and they had quite high levels of some of the nastier pollutants like the small particle stuff. And when we sort of examined their house, indeed, lots of these small particles were in the house. And so what the scientists said is, we are in front of some of the houses.

We're going to just put some plants, basically some small trees, silver birch in tubs, and see what happens. And I thought a few silver birch trees are going to make no difference whatsoever. But surprisingly enough, yes, the houses where the silver birches were in front, the levels of pollution in the houses was lower. And that seemed to be because the silver birches were capturing the pollution in the leaves. And then when it rained, they were sort of flushed off and they went down the sewer. So we thought houseplants. now nasa had done an experiment in the uh late 80s where

they had in an enclosed space they had increased levels of what are called volatile organic chemicals these are things like you know when you have air freshener these things uh you know they produce some quite nasty stuff like benzene which is not terribly good for you indoor pollution so what they've done is they've sprayed some of this stuff around, put some houseplants in an enclosed space. And indeed, the houseplants had reduced levels of benzene and also, you know, basically hydrated the chamber more. But people said, well, that's an enclosed space.

So, you know, what can you expect? But there was another group in Australia who did it in open offices. And again, the introduction of houseplants had quite a big impact on these volatile organic compounds. And plus, you know, people kind of liked having them around. And indeed, what they demonstrated is when you take the plants away, people really miss them. You need quite a few, ideally in a sort of small office.

I don't know how big your office is, but if you had five or six of them in there that could actually make a difference both to the quality of the air you're breathing how hydrated it is possibly but not very much carbon dioxide but again which i you know never underestimate it the power of the placebo that you just kind of like having a living thing there and as long as you look after it you'll feel a sort of a love for this plant as well there are quite a few epidemiology studies about depression and that being lower or protected by people who live in the country rather than urban areas and having gardening as a hobby so actually gardening as a hobby has come out of a number of surveys as being protective for your mental health. And what's also interesting is we looked in the twins and obviously we found that

gut health was on average better in people in rural areas than people in cities. So this is things like gut diversity and generally having more species and assuming a better immune function. And that was also associated with lower depression levels. So it could be that people are out, but it's not rather than just the plants themselves, it's actually people touching nature, getting those microbes from the soil and having a better exposure

to the general healthy microbiome around us that is healthy. And that's one reason. Some cultures actually have school trips, like Japan, to go and hug trees and go into the forests as a regular part of their activities, whereas in England it would just be in a concrete playground. But they really appreciate the concept of walking in nature

as a regular event for their health. Hi, I have a small favor to ask. We want this podcast to reach as many people as possible as we continue our mission to improve the health of millions. And watching this show grow is what motivates the whole team at Zoe to keep up the really hard work of creating new episodes each week. So right now, if you could share a link to the show with one friend who would benefit from today's information, it would mean a great deal to me. Thank you. I love this idea. I normally have a great big plant right behind me, but since it's the winter

in the Northern hemisphere at the moment, I have it moved over right by the window because it's pretty miserable at this point where the sun is just starting to come back up. So I can sort of shift it back into the darker end of the room. Absolutely. And you can also grow herbs. I and Tim, I'm sure, very enthusiastic about herbs. Rosemary is a brilliant herb to grow and smells fantastic. You can grow indoors, outdoors. It can be part of your five a day, 10 a day. Herbs and spices, particularly herbs, are sort of ignored as part of that thing. But I love adding all sorts of strange and wonderful herbs to the food I eat. Varies it, but it is a contributor to your kind of gut health.

Wonderful. Well, we've added the houseplants to our life now. I feel that was fun and easy. Now let's talk about something that everyone knows they should do, but most people are not quite so excited about. Let's talk about exercise. And I think this idea we started with actually, which is whether or not you might enjoy it was interesting, but also the sort of exercise that might make sense. And, you know, Michael, I think this is something you've sort of explored a lot through your career. What's your one thing on exercise? That it's a brilliant thing to do, that you need to do varied. Essentially, there are three types of exercise you need to prioritize. Aerobic exercise, running, walking, swimming, cycling. Then there is resistance exercise, which a lot of people forget about or

don't want to do, which is press-up squats, lifting weights. And the third one is balance, because balance is an incredibly important part of being healthy and growing old, and it falls off pretty fast. So you need to do all three, but some people are more enthusiastic about it than others. So I'm actually okay about doing the press-ups and squats, but I am not so crazy about the running. And indeed, I took part in an experiment a while ago where I got together with some enthusiastic runners. And this was at the University of Nottingham in England. And we were actually measuring something called endocannabinoids. Have you come across them before? That sounds very complicated.

They're essentially a cannabis-like substance, and they are produced by your body in response to a variety of things, including singing, which we touched on briefly, but also exercise. The thing is that some people get a big hit of them, and some of us don't. So in this case, what happened is they took some blood samples before we went for a run. I was with, as I said, enthusiastic runners, came back, measured our endocannabinoid levels. Mine had not shifted an iota. If anything, they'd probably gone down. Whereas the other three, they had shot up. They basically, they had such a good time.

And one of them, interestingly, suffers from quite serious depression. And you could see the lift in her mood. And then over the course of about six hours, as the endocannabinoid levels dropped, you could also see that she was becoming more withdrawn. And she now runs ultramarathons as her way of self-medicating. You know, about 10 years ago ago we did do a twin study, several thousand twins, and asked them about exercise participation and found that there was a clear genetic basis not only on sort of, you know, how regularly they went to the gym or how regularly that they went

for a run or walks. that would support the idea that everyone has slightly different thresholds, if you like, that's genetically hardwired. It doesn't mean they can't exercise, but their preference would tend to be similar in the identical twins compared to the non-identical twins. So it suggests there is some genetic threshold, but clearly, if you have to run you'll run you know if there's a saber-toothed tiger you know about to uh maul you you'll run but i think getting that pleasure from it it could be that some people get more pleasure from lifting weights as you said others get it from running others will get it from other forms of stress or relaxation

and in a way that's that gives the our tribe this sort of diversity and greater survival so we're not all like lemmings and we just you know as soon as anything happens we all go off and run a marathon you know that would be a bit a bit not all those calories yes start to death a week later yeah but but they think our ancestors generally were doing brisk walking uh rather than running and certainly when i was with the Hadza tribe in Tanzania, hunter-gatherers, they just walked at an incredibly fast pace, which I couldn't keep up with. And they could do that for very long periods of time. And I've often heard it described as getting endorphins from exercise. Is this just sort of

like people not really understanding the science and is your cannabis-related substance that I can't pronounce, is that the same thing or is that something completely different? It's the same in the sense that it's a naturally produced euphoric, if you like. But there was a while where everything was endorphins. But as I said, now people are kind of looking at other things as well. So I think endocannabinoids is a sort of a sexy new kid on the block, although it's about 10 years since they discovered it. And indeed, the reason they went looking for it is because they were aware with the endorphins that this mimicked, or at least if you take heroin or morphine, this was just mimicking something that we naturally have.

So they thought with cannabis, cannabis kind of gives you a high. it makes you feel good, it makes you feel euphoric. Presumably, there must be something in your body which does the same thing. And that's how they came across endocannabinoid receptors. And then they started researching this thing. So also some suggestion that if you respond in that way, you get a big surge that also gives you the munchies, because I'm not a big cannabis consumer, but I am told that it gives you the munchies because I'm not a big cannabis consumer, but I am told that it can induce the munchies. So for some people, when they go for a run, they want to eat a lot afterwards. Other people, not so much so. I think the idea that it's very personal, that's been measured, I find very reassuring because

I do exercise regularly because I'm convinced about the health benefits. And I've never reached that point that I know lots of my friends who just say, oh, I've got this massive high while I'm in the gym doing it. I always feel really good afterwards. And I'm not sure how much of that is from any chemical benefit or how much of it is just knowing that I've finished, I've done it and I feel good that I've done this good thing, but I don't get the sort of buzz through the exercise, which I know some people talk about, particularly around things like running and all the rest of it. And I've always like, it seems really unfair. It seems it would be much easier to do the exercise if you were actually getting pleasure from it. I mean, no one ever complains, oh, eating cake is really hard.

Your body is giving you these great positive pleasure feedback, even though your brain is saying, this is probably not very good for me. So it's very interesting. They've actually been able to measure this and seen that, I guess, you know, the story often of the Zoe podcast, that there's this very personalized differences. And that's starting to be something that you can see really, you know, in the chemistry. It's not just people, you know people pretending that they can't feel it. Well, it's often in the brain, Jonathan.

It's often in that they do these functional MRI scans. Because we don't know all the chemicals. We're just, you know, Michael's talking about some of the ones that are easy to measure. There's plenty that we can't get to at the moment that we'll know in 20 years' time. But they can measure on an MRI scan, which is like a brain scan where bits of your brain light up when they're highly active. And they've done these studies in runners, non-runners, and it's the pleasure centres basically light up. And that seems to be the way we can measure this. And there's definitely variety in that.

And I think one of the big challenges in public health is how do you get people who say, I really don't like exercise. I've never liked it. I hated it at school. It doesn't make me feel good. I just feel bad afterwards. How do you get them to exercise? And I think that's, Michael, I agree, that's a

challenge. Absolutely. And they are the majority, unfortunately. The other thing we know is that when you do surveys of people, they say, yeah, of course I do 150 minutes. But when you actually fit them with accelerometers and things like that, you find they're just lying. And the number of people who hit the guidelines is, in some cases, less than 10%. So that is the challenge of our time. How do you make it pleasurable? And you can make it more pleasurable by doing it with a friend. You're more likely to persist with it if you've got a friend running with you, if you've got a friend down the gym.

The only reason people really employ personal trainers is because the personal trainer is going to dig them out of bed and make them go for the run. And there is some companionship in that. So it's how do you manage that? Just telling people that exercise is good for them is not actually going to make them do exercise when the alternative is sitting on the sofa,

eating eclairs and watching the TV, which is fun for most people, although in the long term, extremely bad for them. So just exhortation alone ain't going to do it. And so I'm a kind of great believer. You kind of got to build it into your life. I live at the top of a steep hill. And so I always cycle to the station.

It's just over a mile. And I say to my wife, under no circumstances, pick me up. Even if I ring you up and ask you to come and collect me, say no. But that will force me to go up the hill. And then I put in little bursts of hit while I'm going up and arrive sweaty and hugely resentful, but at least I've done it. That's brilliant. So do exercise with a friend, you know, then your personal trainer is a way of also creating that, build it into your life. Any other tips that you've picked up? Because I think we all know how important exercise is for your health. Any other little tricks that you want to share?

I think as a regularity as well, find something that can fit into your life. Don't go say, I'm going to run a marathon because you probably never will. As I was saying about the press-ups and the squats, I do them first in the morning because I know if I don't do them then I never will. And so expecting to go down the gym every evening at 6 p.m. is probably unrealistic for most people because it's not going to fit into your life. So ideally have something which is triggered by something and which is more likely to be something you'll actually stick to rather than something you'll do. I know a lot of people who've run marathons and who never ran them again. It was so awful. They ticked it off their list, it wasn't you know that isn't

going to set you up for the rest of your life that's kind of a one-off event great fun very stimulating lots of people shouting and cheering but find something just something and even better if you find something you actually enjoy whether it's playing football whether it is you know fencing whether it is going and just going on a treadmill is miserable for most people. And that's why they go down, they run on a treadmill. And after they've done that for a couple of weeks, they go, no treadmill, no, not going to do that ever again. So there are very, very few people who think that running on treadmills is fun. I don't know if Tim is one of them, but I'm certainly not one of them. No, it is soul destroying. But I think it's little things like, you know,

you put the tea on or you're waking up to brew or you've got five minutes, you know, that's the time where you can just do some exercise or squats. And, you know, I remember there are people like Rang and Chatterjee who have got little programmes to get people clues that things you do in your life that you can just build in every day so a small amount every day is often much better than some big splurge at the gym every every two weeks and then you go and you know have a burger afterwards to celebrate so i can say there are

things like you get told you should put your trainers down by the front door so you see them but to be honest i see the trainers by the front door and i just chuck them in the cupboard i don't go oh i must put the trainers on to go for a run so i found for me what works is getting straight out of bed and doing some exercise if i found if i wait and i say okay i'll just uh read the news on my phone uh i never go it's only when you when your brain is too fuddled to stop you doing it, do you actually get up and do that exercise and go down maybe and do your stretching, your sit-ups and whatever. If you delay it, you're lost.

That inner brain that says, oh, it's nice and comfy here, Tim, you don't have to get up anymore, will always win. So it's all about making it effortless. So either routine or effortless, they're the key things. One of the other interesting and odd things I came across when I was writing Just One Thing is the benefits of walking downstairs or indeed running down the hill,

which I thought was odd. It's known as eccentric excise or eccentric excise. Have you come across this? There's a group in Australia and they did this sort of wonderful study where they got a group of overweight people, and they asked them to basically either walk up or down, randomly allocated them to walking up or down a 10-storey building. And one group had to take the lift to the top and then walk down. The other group, they walked up the 10 flights, and then they took the lift down. And they had to do this twice a week for, I think it was about eight weeks. And what was really surprising was the group who were walking down the stairs got the most benefit

in terms of impact on their blood sugar levels, blood pressure. They burnt a few more calories and also it was better for their bone density so the reality seems to be that walking down is in and of itself quite a serious form of exercise and so i thought that was kind of just kind of wonderful and weird and one of the lessons you draw from it is when you're doing the press up and the squat what you want to do is really slow down the descent that actually a lot of the benefit comes from when you're going down not from when you're going up yeah i've noticed that when i'm doing mountain walks with some keen alpine friends the next day it's all my you know those eccentric sort of muscles that absolutely kill me not the quads or you know the usual ones in the front so it's all the back and

the buttocks that really hurt but some people can't of course i i used to be a rheumatologist and all the early arthritis patients all complain that the first sign of arthritis is walking downhill because it definitely puts more strain on the knee than walking uphill which people find very strange and they say well it can't be my arthritis because i'm fine when i go uphill. But the first sign of usually knee arthritis is pain walking down the stairs. I've also recently been looking at the benefits of walking or indeed running backwards.

There's a wonderful piece of research. I was talking to a researcher who's been doing it for 20 years. I said, why? Why on earth would you want to do that? And she said, basically, it was just an area which hadn't been explored by anybody else. And so, you know, you publish in the areas where no one else was going to compete with you. But she said, you know, footballers often train running backwards and supposed to be good for balance and also for back pain.

Again, maybe one to think about before you try at home. Well, Michael and Tim, thank you so much. I think we could keep talking about this for hours, but I think we're unfortunately going to have to call time. I'm going to do what we always try and do here, which is a sort of a quick summary of what we've covered. And please correct me if I got everything wrong. We started off talking about some of the best simple things that Michael had discovered through work for his book and podcast. I think we started with cold showers, which amazingly might really have some health benefit. My takeaway is the verdict is out, but definitely worth further investigation. And that if you go outdoor

swimming, you don't want to do it on your own because you might suddenly forget who you are and who you're married to. We then talked about houseplants and the gardening, and I think the verdict was pretty compelling that there really is benefit to both of these things. And I also took away the tip that if you're not so good as green finger, then you can't kill rosemary. It'll smell great and you'll be able to eat it. So there's a sort of all-round win there. Then we talked about deep breathing. And I think, again, surprisingly, sort of strong evidence this can have a very direct impact on your anxiety, how your brain is working. Again, not as much scientific investigation as you might hope. And I think another thing that might be very interesting, Tim, for sort of further investigation at large scale.

And I took away that mouth breathing is bad, which is bad because I am a mouth breather, I'm told, when I go to sleep. And I'm not sure how to fix what you do when you are asleep. So we're probably a whole podcast on how to address this. And then I think at the end, we talked quite a lot about exercise, which is obviously a big thing within which there are many simple things. We learned this new word, endocannabinoids, which basically means I get to make my own cannabis. Some of us have it, some of us don't, but everyone should be doing more exercise. And I think we had a few brilliant suggestions from just brisk walking and eccentric walking, which isn't walking in a funny pace,

apparently, but it's going downhill, being better than uphill. I love the idea that going downstairs is better than upstairs. That definitely doesn't sound right. And above all, build this into your life. So have some pattern, whether it's regular, doing it with a friend, finding something you enjoy so that this is repeatable rather than just something you do for a little while and then you drop. Very good summary. Yep. I'm with you all the way. Apart from the endocannabinoids, we all produce endocannabinoids. It's just some people appear to produce them with excise and other people don't. They have multiple effects throughout the body and we're only just beginning to unearth, if you like, some of those effects. I'm all for a personal study to understand,

Tim, how I can produce more of these. I'm happy to be the guinea pig. And I'm hoping that you tell me that I just watch lots of TV and this solves it. But I have a feeling that it will require more than that. No, it's going to be lots of ice baths for you, I think. I hate this idea. And I can tell that I'm going to be taking an ice bath later this year for certain. Brilliant. Michael and Tim, thank you so much for joining us. Really enjoyed it and I hope we can do it again soon. Thank you.

Thank you, Michael and Tim, for joining me on Zoe's Science and Nutrition Today. If based on today's conversation, you'd like to understand how to make sustainable changes to your diet to improve your health, then you may want to try Zoe's Personalized Nutrition Program. Your Zoe membership comes with our app and access to our nutrition about Zoe, you can head to joinzoe.com slash podcast and get 10% off your purchase. If you enjoyed today's episode, please be sure to subscribe and leave us a review as we love reading your feedback. If this episode left you with questions, please send them in on Instagram or Facebook and we will try to answer them in a future episode. As always, I'm your host, Jonathan Wolfe.

Zoe Science and Nutrition is produced by Fascinate Productions with support from Sharon Fedder, Yellow Hewins Martin and Alex Jones here at Zoe. See you next time.