The Hidden Connection Between Depression, Anxiety, Weight, and Your Gut (and What to Do About It) | Tim Spector, MD
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I talk about five rules, really, to improve your gut. First is try and get 30 different plants a week into your diet. The second rule is fermented foods, trying to get at least three different types of fermented food in every day. Third, I'd go for eating the rainbow and thinking about color and that.

The reason is that Carla tells you the chemicals in those plants that are helpful for your gut microbes. And the chemicals are called polyphenols, and they are rocket fuel for your gut microbes. And number four would be giving your gut a rest. So again, there's time-restricted eating, increasing evidence that if you can leave, you don't have to do massive fasting, but if 12 to 14 hours will give benefits to your metabolism for your gut microbes and fattening.

Finally, it's switch from eating ultra-processed food to real food. And that means quality, not calories. If you remember five things about gut health, do that. Because the food choices you make are most important choices you can make for your health. And these are things we make multiple times a day. 60% of the US diet is fake food. And

We're now getting the science to show why it's bad for our gut microbes, why it makes us overeat by 25%, why it's been making us so sick. So what if I told you that the state of not just your physical health, your weight, your energy, your risk of disease, but also your mental health, including feelings of depression and anxiety and low mood, just might be coming from the bacteria in your gut? Wait, what?

Sounds a little bonkers, right? But that is what cutting-edge science focused on the microbiome is starting to reveal, which is why I wanted to sit down with Tim Spector, professor of epidemiology, leading microbiome researcher, and co-founder of ZOE, the Cutting Edge Science and Nutrition Research Organization. A true pioneer in microbiome research, Tim stands at the forefront of this field and is among the top 100 most cited scientists in the world.

In our conversation, Tim takes us deep into the gut microbiome, that vast community of trillions of microbes that live within us.

I'm pretty well read on the microbiome, but Tim revealed so much cutting-edge science I had never heard about and talks about the stunning relationship between the critters in your gut and everything from inflammation, immunity, cancer, heart disease, and more to depression, anxiety, energy. He explains how these tiny organisms produce vital chemicals that impact nearly everything in our minds and bodies.

We also do a bunch of myth-busting, by the way, and talk about what the science doesn't really say these days, even if maybe you're hearing it does.

We talk about where the science is heading from here. And then Tim shares his really straightforward five keys to building or rebuilding a vibrant microbiome that can literally transform your physical and mental health and along with that, potentially your life. So grab a pen and get ready to take notes because this conversation could quite literally change your life from the inside out.

Quick note here, by the way, Tim is also one of the lead scientists and co-founders of Zoe, a groundbreaking research and nutrition venture that he mentions. Zoe is also a sponsor of ours, and we're big fans of the work that they're doing. But I want to let you know that this conversation was arranged completely independently of that relationship as a way to share deep wisdom from a leading scientist on a truly transformational and emerging field of human health.

So excited to share this conversation with you. I'm Jonathan Fields, and this is Good Life Project.

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You know, really excited to dive in. I know you have done a lot of work really focusing deep on nutrition, the microbiome, and its effect on health, on how we live, physical health, mental health. I think a lot of people have heard the phrase gut biome or microbiome these days, but maybe aren't entirely sure what it actually is and why we care so much. So I think that's probably a good starting point for us.

Sure, yes. The gut microbiome is the general term we give for the community of all the little microscopic bugs that live in our gut. And we're talking mainly about the lower part of our gut, right? That is the large intestine, the colon before the rectum, right?

right at the bottom. So it takes a while to get there. And there are trillions of these guys there, as many as there are cells in our body. They're a mix of bacteria, they're viruses, they're fungi, yeast, even some parasites we've found that are normally in everybody. The way to think about them best is it's like this

collection of all these organisms that produce chemicals so they're like a big collection of your super pharmacies that can give you any vitamin or drug or neurochemical that you want and

And we're slowly discovering this is what they mainly do. They produce all the chemicals that our body can't produce itself. And that's why they're so crucial to us in terms of our brain function and our immune system and our metabolism and regulation of pretty much everything, surveillance of preventing aging and cancer, et cetera, et cetera. So that's the way to think about them in a very broad sense. And I'm

And clearly, we're just learning about them in the last 10 years. And we're learning how to feed them right. And we can't live without them. So they're not an optional extra. I think that's the key issue.

insight we're getting now. Yeah, that was one of my curiosities. You know, if you took, literally had a way of stripping the microbiome outside of a human being, it sounds like life would not sustain for very long after that. No, they've done it in mice to some extent, and they don't develop a brain normally. They don't have a normal immune system, and they're

They lack all the normal reflexes, etc., that we humans have. So they're absolutely crucial for how we interact with our environment and how our immune system works.

It turns out that our immune system is quite important for our brain now, and therefore they really are crucial. And, you know, obviously we can get by with less of them because we have less than our ancestors already. We have about 50% less than we used to have. So you can get by with a crucial, you know, with a sort of subgroup of them. But clearly it's best if the more you've got, the more diverse species you have. And we've done some studies now over the last few years with Zoe on this that show that

if you've got lots of different species, that means you're getting a different range of chemicals produced. And they're actually very fussy, these guys. So you think, oh, well, just give them anything to eat. It doesn't matter, you know, just like the average American, you know. But actually, they're real aficionados. They produced a paper ship

showing that there's a microbe that only eats coffee. It is so fussy that it waits around. Even if you haven't had a cup of coffee for five years, it just stays there in a suspended animation, waiting for that coffee, and then it will go crazy and reproduce and produce all kinds of chemicals, etc. So

That's the way to think of our gut microbes. It's a bit like this jungle or a fish tank, whichever way you find easier, or a garden that you're trying to nourish to get all the different characters on board, big and small, all working together because they also feed off each other. If one's eating a

say, I don't know, a bit of cabbage or something, one will start and there'll be another microbe that will take the discarded bits from the first guy and then another one who takes the discarded bits from the second guy. So nothing's wasted. They're a perfectly sustainable little environment there. And so they make the perfect garbage collection and recycling system.

So let's dive in a little bit more here. You know, I think it's, you've made it clear that this is absolutely critical for health. And you mentioned a couple of different things. And I'd love to see if I can get a clearer understanding. When we talk about the gut microbiome, then in the context of conditions that we might experience that we don't want to experience diabetes, cancer, heart disease, how does a microbiome actually work in the context of disease?

these types of conditions? It works in a number of different ways because obviously we're dealing with trillions of organisms and thousands of different species that have different genetics and produce different chemicals. So in a way, if you think of them as a multiple pharmacy, each of those drugs they're producing have different effects on the body. So for example, for heart disease,

You can have microbes that will be important in reducing, say, blood cholesterol, eliminating the fats from your body rapidly. And there'll be other microbes that are telling the immune system to dampen down inflammation so that the vessels are calm and relaxed. And there'll be other ones that are regulating...

your blood pressure control. Also, regulating your medications for, say, blood pressure. Even statins, we think, are regulated partly by your gut microbes. So they sort of work really across the board. And in the brain, we know...

a little bit that they, as well as also controlling inflammation, which may have a, which is this sort of stimulation of the immune system. So it's running a little bit hot when it should be off. So it's like these burning embers that just keep going and irritating the system that could, you know, be involved in mental disorders. But specifically, we know that microbes produce neurochemicals that affect the brain, such as serotonin, which is a precursor to

things like dopamine, which is important in emotions and is probably...

involved to some extent in depression and those kind of conditions. It also produces something called GABA, which people might have heard of because when you take a valium or a benzodiazepine, that's the neurochemical that's altered in that state. So it works in a number of different ways. And we're only just coming to grips with it, really, because it's got such a broad reach, the microbiome. Chemicals

many of which we still don't understand what they are or exactly what they do. So that's why there isn't a single mechanism that you can say, ah, microbes do this or microbes do that, which is what we thought perhaps 10 years ago. Yeah, I mean, so it's interesting, right? Then we're at a point now, it sounds like in the science, where we can draw a line between microbes and a particular outcome, but in order to actually sort of like fill in that line between microbes

the bacteria or the existence or lack of existence of a particular bacteria in your microbiome and a particular effect in your physical health or your mental health. We're not there yet, it sounds like, but we see that there's an outcome, but we can't trace the mechanism with a lot of accuracy. Is that right? That's right. I think we're just scraping the surface of that. We know from...

Big studies like we've done at Zoe, where we have over 200,000 people now in a database to see those correlations between what your microbes look like and all these medical conditions. And we also know from small animal type studies that you can induce things like anxiety or depression in mice and transfer it from one mouse to another by transferring their microbes.

And then you've got other test-tube experiments giving you little teasers about what's going on. But I think we're going to have to wait a few years to really see exactly what the causal mechanism is. At the moment, we're just guessing that this is the main one and we can talk in generalities about...

What's pretty clear to me is that if you think that the immune system is key to most diseases, so we're talking heart disease, we're talking cancer, surveillance, we're talking allergies, autoimmune disease, and to some extent mental health, then if you're getting a stable immune system that's working really well, we know that most of the immune system is 70% of it is in your gut, talking to your gut microbes. So for me, that's where the answers lie.

It's the communication. So it's an extension really of our immune system. And it's the way the immune system talks to our environment through the foods and through our gut. That to me is a bit of an aha moment when there's a rather vague term, this brain-gut connection and this immune, it's the brain-gut-immune connection that's actually really important that sort of makes sense really because the immune system is also so much part of aging.

and making sure that it's perfectly tuned to our environment, not overreacting, not underreacting, not chasing red herrings, you know, going around...

putting out fires that aren't really there. And it's really focusing on cleaning up the body, making sure it repairs itself. It's fighting cancer when it's really early, before it's seen. It's helping drugs to work, all these things, and stopping allergies and autoimmune disease. And you can see how just the epidemic of food allergy in the last 50 years, which we can't explain by genetics, has got to be due to something like the gut microbiome changing so radically.

That's a reflection of things like our poor diet. I want to make sure that I got something that you said right, though. It sounds like you said there have been mice studies that induced a particular type of bacteria in the mice. And then we transplant those. That balance is correlated with mental health challenges, with depression or anxiety.

And you can literally transplant that bacteria into another, I'm assuming mouse, because I'm assuming you wouldn't be doing this in people now, and see the same psychological manifestations just by taking the bacteria and putting it in another mouse. Is that right?

This is the lovely thing about the gut microbiome, that you take these very big human experiments where you're just looking at epidemiology, just taking, you know, it was hundreds, then thousands, and now we're doing hundreds of thousands of people. And you see these correlations, but you don't know which way it's going. Is it cause or effect? And then you look at mice, and you can take these sterile mice, and you can put human microbes in them from, say, anxious or depressed people. And

you can induce anxiety and depression in those mice. And that's a pretty good evidence that that's a causal relationship. And then once that mouse has become anxious or depressed, you can then induce that in other mice. And they've done other experiments where not in sterile mice, but just by inducing a series of

really stressful experiments in mice, they take their microbes and then they can then transplant those from the anxious mouse into a calm mouse and make it anxious. So in a way, that's sort of suggesting that mental health is to some extent infectious, which is a sort of amazing thought. And they've done these other experiments with things like diabetes and obesity as well.

Hasn't been quite as marked as with mental health, but and also in protection against cancer, things like this. So we're able to show what give us an idea of what's going on in humans by these really clever mouse experiments that they've been developing. Yeah, I mean, that that is wild. I mean, to be able to to take a human being who is experiencing depression or anxiety or mental health challenges and

transplant some of their microbiome into a mouse and then have that mouse exhibit similar things and then transplant from that mouse to another mouse, that really does speak not just to correlation here, but to causation. And then if you start to expand that out, I mean, just the notion that I think for a lot of people, if they think about, well, I've been struggling with depression, with mental health, with anxiety, and the notion that it might in some way, shape or form have to do not just with what's happening in their brain,

but actually in the balance of bacteria in their gut is kind of mind-blowing. You know, I wonder what the state of research is in terms of looking at that more expansively with humans right now. Well, obviously, it's a very fast-growing area of research because, you know, we've had these, certainly in psychiatry, there have been these different models of mental health. You know, initially, you used to blame your mother or your parents for,

for giving the wrong personality that there was this thing about the refrigerator mother and you know Freudian sort of idea that in a way it was your environment that caused everything then we had this the genetic revolution and said it was this genetic susceptibility and then it was all rather inevitable whether you had a mental health disease and

And suddenly, the last 10 years, it's all shifted and said, well, actually, you know, the gut and your gut could be this link between both your genes and your environment, particularly your diet that's causing this. And you can change a lot of that through this gut-brain connection. It is another way of, in a way, drugs getting to your brain and altering your…

your mind. So I think it's, you know, it's going to really revolutionize psychiatry because at the moment, because we separate the mind and the body, no one talks about diet. You wouldn't go to see a psychiatrist and you say, tell me, what's your diet like? Well,

Whereas probably I'd say if I saw someone suffering from, say, depression or anxiety, that's probably the first thing I'd now say before discussing antidepressant medication. And there are human trials now of people with mild depression saying that if you give a gut-friendly diet,

you get about 30% completely in remission and doing better than many trials of the drugs themselves. So I think it is an exciting time, but it's really breaking tradition and changing people's whole idea of what

mental illness is as well as other areas you know of medicine where people have had a rather closed view of it for so long and think oh well it's just drugs there's any one way to deal with this it's genetics it's drugs it's things that you know doctors understand suddenly moving into these new areas the

doctors haven't been trained in, like gut microbes and diet, you know, it's often tricky and the patient may often know more than the doctor in many instances. Yeah, I mean, it also makes me, where my brain is going with this also, I'm wondering now, you know, and I would imagine there'll be some research on this at some point, you know, if you point to the major pharmaceutical interventions for mental health, often some form of SSRI, SNRI, it now is making me wonder whether the

method of action is really directly on the brain or is it potentially on the bacteria in the gut, which then actually is the thing that changes the state of neurotransmitters in the brain. When you really start to map it out, it's kind of fascinating. There have been some studies showing that at least 50% of all the common pharmaceuticals are interacting with microbes in the gut for their action. And that's

That was pretty wild because that's just what we can show. It could actually be 90%. We're not absolutely sure. But in mental health, we know that antidepressants, the SSRIs, these are serotonin reuptake inhibitors, the microbes break down the drug and

and can actually inactivate it. And so because we know all of us have very unique gut microbes, some people who take these drugs can be completely ineffective, not because they're not taking it properly.

they often get blamed for, or they're not taking the right dose. Just they have the wrong set of gut microbes that are inactivating them. And that's why about a third of people who take them really have no benefit from them. So that's just one example. But if you take Tylenol, for example, then you get a similar reaction. Some people never get any pain relief from Tylenol. They say, I've got to take aspirin. It doesn't work for me. Or I've got to take ibuprofen.

Whereas others, fine, it works. And again, it's the microbes that are interfering this process and inactivating one. And in cancer treatment, you know, more importantly, more and more people are having immunotherapy. If you've got melanoma or kidney cancer or increasing prostate cancer, increasing range of

cancers. We did a study in Europe, which I was leading, showing that the most important fact about whether you were still alive at 12 months with your end-stage melanoma was the state of your gut microbes. So if they're not in the right state, they will either inactivate the drug or the drug doesn't work. And so this is suddenly one of the most important things that it

Everyone needs to know as they get older and they get exposed to these kind of illnesses that no one has really been thinking about. And there isn't, aren't really enough specialists out there to actually spread the word. So it's all coming from researchers like myself because they're just, you know, there's no medical specialty behind this yet. It's too new, but things are moving so fast. It's really important people know how important this is because it also comes back to this message, how important diet is. Yeah.

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I want to dive into a bit of the do's and don'ts here in terms of like, how do we actually build a healthy microbiome and avoid the things that might actually make it less healthy? But there's one other question that I wanted to ask you before we move on. We've talked about the impact and the potential links to things like cancer, heart disease, autoimmune conditions, mental health. Now, I'm curious about whether there is a clear link between the microbiome and weight.

It's something that so many people struggle with on so many different levels. What's the state of science on that? Well, there are different correlations in all our studies. So people who have the greatest weight tend to have less diverse microbes than people who are thinner.

And the mouse studies, again, if you take the microbes from someone who's skinny and put them into a mouse, they won't put on weight as fast. And if you take, say, from their identical twin sister, which is what we did, which is my background in twins, you'll show that actually they will put on weight when they're overfed. So we're sure they have a role. How big it is, we don't know. Yeah.

And we were quite excited 10 years ago because in a way, a lot of this microbiome stuff kicked off that maybe just by transplanting microbes from a skinny person to an overweight person, you could completely change everything. And it turns out that didn't work. So lots of private clinics were trying it and people were trying it at home and with their own MagiMix and all sorts of things you shouldn't do at home. And

generally they failed or occasionally they went wrong and people actually gained weight because the microbes were the wrong ones. So we think it has a role. I don't think we know enough about it yet to be able to manipulate it properly. And clearly, as always, science is perhaps more complicated than we thought. And because we haven't worked out yet what the microbes, key microbes are that affect the key processes of weight gain. And of course, with

Zempik and Manjaro, we've realized that it's not so much metabolism in the gut that's important, but it's appetite levels in the brain. People are now looking for what are the key microbes that affect appetite

Hmm. And maybe targeting them with pre or probiotics. And there's some evidence that microbes do produce GLP-1 themselves, which is this appetite suppressant. But fair to say, I don't think we've found the magic bullet yet. So it

But it sounds like it's going to be a more targeted therapy than just taking everything from another person and sticking it in you. So I think we'll have to chat about this in a few more years and see if there's a microbiome equivalent of a Zempik that's going to come along. But I think someone will find it and...

you know, again, it just shows that within us, we've all got this amazing pharmacy and we just got to know how to feed it right or how to program it in order to bring it out. But

I would say that the science isn't there yet to offer the exact recipe for weight reduction, other than to say that generally people who improve their gut health do slowly improve their weight, but it's not dramatic. And it's a general correlation, and it could be related indirectly to things like inflammation and the fact that if your body is well balanced in control, you

you're less likely to be putting on weight, but maybe also less likely to be craving some of these foods that upset that balance. Yeah. I mean, it'll be fascinating to see that research, especially in the context of cravings and appetite, you know, because if you can affect it on the level of the brain and the actual, the initial impulse, that would be really fascinating. Just as an example, when we put

We've put hundreds of thousands of people now on the ZOE program, which is the idea that you can give people a gut-friendly diet, cut out sugar spikes, reduce the fat levels, move them towards a higher fiber diet.

the first thing we see is an improvement in mood and energy. So way before anything else. So we don't understand why that is, but clearly the brain is the first thing that's being triggered by these changes in our gut microbes. And we do see significant changes in our gut microbes when you measure it, but people feel better first. And we'd

you know, we didn't even think to ask them initially because it's not something that in medicine we tend to ask about energy levels. But that's what we found. And we think it's due to what's going on in the microbes and perhaps the chemicals they're producing. So I want to dive into some of the way that we would change our nutrition and our lifestyle. But I'm also curious about the impact of a couple of other things before we get there. One is, I

I think something that I've experienced this year, which is I have been on antibiotics multiple times this year from health procedure or medical procedure where it's just kind of prescribed by rote because this is what you do. I think we've probably all heard on some level that this is not a good thing for your gut microbiome. But talk to me a little bit more about what actually happens here when you take a systemic oral antibiotic and also...

What can we do about this if we're in a situation where it is recommended to do that? Yeah, great point. Well, I think the average American, by the time they get to 18, has already had about 20 courses of antibiotics. And it carries on, about one a year on average. It's just crazy.

And this is like three or four times more than you'd get in Scandinavian countries. So there's massive over-prescription, probably due to the litiginous nature of American medicine. Everyone's worried about something going wrong and somebody being sued. And so...

When in doubt, take this stuff, which we used to think was pretty harmless. And that's probably still taught in medical school that, you know, the risks are minor. Maybe you get a bit of, you know, stomachache, occasional rash. But, you know, these are good drugs. And they, yeah, they definitely save millions of people's lives. So I'm not saying don't use them.

But we now know that they radically affect everyone's gut microbiome when you take them. And what differs is, depending on your individual makeup and the individual antibiotic, it can vary between about a month or

to years before your microbiome comes back to where it was. And in that time, it's disordered, it's not working properly, and your immune system is impacted so that it won't be working as normal as it's supposed to work. And you may end up getting more infections in that time. Studies in

in epidemiology following kids who've had a lot of antibiotics show that they actually have more food allergies than kids without antibiotics. And there are potentially other consequences as well, maybe more obesity as well in children, because that's one reason why they give chickens and animals antibiotics in low levels is to feed them up, make them more obese. So

obviously we ought to be thinking differently about antibiotics and say, well, actually it's a balance. It isn't all good. You've got to weigh up the chances of having another infection. You know, I had a...

a tooth implant and the dentist said oh i recommend uh you take an antibiotic you didn't know i was interested in the guts and um he was a bit surprised where i said well rather not is that a problem he said no well some dentists say you know you don't have to so it's not universal it's just you know we generally recommend it because it reduces the risk of an infection i said yeah well

do you tell your patients that there's a risk of, you know, getting more flu next year or more COVID or, you know, having other problems? They said, no, of course not. Why would I do that? So, you know, generally you take medical advice, but if they do offer you a choice, then I think you've got to weigh it up, you know, individually and ask them, you know, what are my risks of an infection? Is it usually they're sort of one in 5,000 or something like that?

And you say, well, if I get infected, you know, am I going to die or just come back and it just takes longer to sort me out? So I think we just need to think about all medicines a bit more carefully rather than just taking them routinely because we already have a pretty weak gut microbiome in the US. It's, you know, we've lost half our species. It's probably the worst microbiome in the world.

because of all the bad things we've been doing to it. So we don't want to keep harming it. And some people, once they've taken antibiotics, if they're having them every year, they never recover. They've always got a very damaged system, which means their immune system's not working properly. And that really worries me that we're doing this. And particularly for children and particularly...

unnecessarily. So yes, they save lives. And I'm not saying don't take them ever, but I think really be more mindful about when you do take them and take for a short period of time. And I always tell people to really up your game on your diet and what else you can do for your gut microbes. Yeah. So that's antibiotics. I'm curious also about the potential impact of

if any. I don't think I've seen research on this. Is there research on sort of chronic stress on the microbiome? Well, psychiatrists do recognize there's a mixture of anxiety and depression is a diagnosis. Certainly in Europe where you get a mix of the two and that

They see a very disordered microbiome in people who have that, who are anxious. They've done a few small studies in humans in stress. They're not particularly convincing, but they've done some things, exam students and things like this, showing a potential effect of the microbiome. But the best studies are, again, in mice, where it's very easy to induce stress in mice.

And they can rapidly change their gut microbiome to what looks like a very stressful microbiome signature, producing stressful chemicals, making the whole thing worse. And they can, again, transplant it from a stressed mice to an unstressed mice, and that

new mouse would become rather stressed and show stressful patterns. So I think we have to assume that that, you know, again, it's the gut microbiome is both reflecting its environment, you know, what's going on outside as well as someone causing it as well. So I think we,

We react to stress, you know, just like people, I think with poor sleep and other problems, you can induce problems in your gut microbes. So, and you just mentioned sleep. I'm curious whether, yeah, it seems like all these different things, there's almost like a circular relationship. Like one triggers this, which then makes the actual symptom worse, which then actually makes the microbiome worse. It's like it creates this...

You can either create a beneficial spike or cycle or a destructive cycle in all of these. I would imagine there's some relationship with sleep in here as well. Yeah. When we talk about gut microbes, we generally talk about diet, but sleep and exercise are also important and important.

Once everything gets out of whack, then a poor night's sleep is followed by changes in your gut microbes, which we think induce changes in what you want to eat. And then if any of the listeners, you know, after a poor night's sleep, when you sleep for four hours, we've done lots of studies now on thousands of people showing that poor night's sleep is correlated with a different choice of food in the morning, right? So your brain's telling you, gosh, I haven't slept.

I'm going to have some really unhealthy food this morning, right, to get me through this. So I'm just going to go for massive amounts of carbs and get a real sugar spike. And I'm not going to worry about the consequences. And you feel really hungry. And that's what you crave.

It's very hard to have a healthy breakfast after you've had a really poor night's sleep. And we think this is all linked to the gut microbes being out of sync, maybe sending chemicals to the brain saying, give me sugar. And so then you get into the cycle of a big sugar spike and then you get a dip and then you get more energy loss and inflammation.

increased hunger and that you go on through the day until you either keep going by that or you manage to get rid of it with a decent night's sleep and you can get back on a flat C again because you're in this storm. So more and more we see this connection between the different balances of the body. It's

It sounds a bit crazy, but I think medical science is catching up with this alternative medicine that's been saying this for years, but without any science behind it, just with anecdote. And we know that the gut microbes, just like humans, do need a regular cycle.

they, you know, they get jet lagged. If you stop, you know, it's a bit like the science behind time-restricted eating, having regular eating patterns, not eating late at night, giving them a good rest is really crucial for their normal functioning. Otherwise they produce abnormal chemicals. And so in a way they're just like us, they need sleep and they need, you know, regular habits. And this is, this is what it's showing, you know, the bodies are

finely tuned machine that works best when it's in a clear pattern that just carries on to doing the same thing all the time, not messing around with it. Yeah. And we'll be right back after a word from our sponsors.

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Let's dip into the nutrition side of this then, because it sounds like that is a lot of where the work is. I mean, more broadly, lifestyle, it sounds like sleep is really important. It sounds like you're sort of referencing exercise, which is probably important as well. But when we talk about what we're taking into our bodies, the big levers really lie there. Before we talk specifics...

What is the sort of, you know, when we think about, okay, so whether we're looking to build the healthiest microbiome possible, or maybe we had a round of antibiotics and we kind of know that we need to recover from that. We need to rebuild from that. Whatever the reason is, you know, whatever, you know, if there's some underlying level of dysfunction in our gut microbiome, what is sort of like the big picture aspiration of what we want to accomplish before we get to the actual, like how we might choose our nutritional choices? Yeah.

do two things to your gut microbiome. One is to improve the diversity of species. So give all the guys there a chance to thrive and reproduce. So we talked about the coffee microbe, which is called loss of the bacta. There's just one example, but there's lots, thousands of other guys waiting for you to give them that bit of

Chinese cabbage or some Iranian carrot or whatever it is. So giving them a diversity to get them to flourish means you're going to get more species. In general, that's been the sort of golden rule up to now about how to feed your gut microbes. But increasingly, just having lots of species isn't the whole picture. And the other thing that we've discovered...

Again, from the ZOE database, which is now probably the largest in the world with food microbes and health data, shows that you want to increase the number of good bugs and reduce the number of bad bugs. And we've worked out there's about 100 of these key microbes in everybody in the US and the rest of the world that we can compare. So you want to get...

more of the good guys, less the bad guys. A bit like, you know, how we describe your blood lipids or your blood, you know, cholesterol levels, good cholesterol, bad cholesterol, get that ratio high. So that's what we're trying to achieve. And we now, we're getting much better at knowing how to do that. And it's essentially through throwing a diversity of plants. So I talk about

five rules really to improve your gut. First is try and get 30 different plants a week into your diet. Now that sounds crazy if you get nervous about how many plants you can eat. It's not all kale. It's nuts, it's seeds, it's herbs, it's spices and it's even different colours of the same species and each of them is a little niche for another little animal down there, a little microbe and

We did studies showing that that's key. And we've just got a paper coming out any day now comparing vegans, vegetarians, omnivores. And it doesn't really matter if you have the occasional bit of meat or fish. As long as you're getting those rich variety of plants, you're still going to have one of the healthiest gut microbiomes. So the number one thing is to get those plants on your plate.

And once you've got that, you're automatically getting all the fiber you need. So we're not so specific. It's very hard for people to start measuring fiber and all this stuff. But if you have some of these more simple back of the envelope rules, it makes life a lot easier to say, I've got to keep thinking about plants. I've only eaten five today. Let's put some more nuts or seeds in.

on my salad or, you know, let's pick something I haven't eaten before. So that, that works really well in practice. So we've been doing this in the UK now and it's really taken off this, this concept of 30 plants a week rather than the sort of government, you know, five a day. It's always the same, always the same juices and things that are really bad for you. So that's,

That's a concept. Yeah, I would imagine also, you know, because some people are like, oh, how do I do this? I have to have 30 individual things. But then so many of us have sauces, like tomato sauce. I mean, how many different plants are probably in tomato sauce? Yeah. You know, so there are probably ways that we can get them without sort of like having them individually also. Exactly. I mean, just to give people an example, I mean, my breakfast is a full fat yogurt with fermented milk, kefir.

And I have a jar where I mix up nuts and seeds pre-mixed, and I've got about 10 plants in there. And so if I add some frozen berries, which gives me about another three plants, I've got over a dozen plants just done in my breakfast. Right. So it's not as hard as it seems. Yeah. Okay. So that's the whole point here. You can sort of slightly fix the system if you're just thinking in that

in that way and you know you're prepared right so that's that's the first rule and it's probably the most important one because the average American we think has you know so much in eight and ten plants a week if they're lucky

and many a lot more less. And, you know, the French fry doesn't really count as a plant. So that was the sad fact. But coffee does. Coffee does count as a plant. Well, I love that. And does chocolate count also? Not Hershey's, but if you get...

Like a good bean to bar. Bean to bar, you know, 75% chocolate. It definitely counts. Yeah. All right. I love that too. Exactly. So, because you've got to remember, you know, people forget where, you know, what are these things come from? And they forget that chocolate and coffee come from fermented beans. Right. So really important to get back to our roots. Yeah. The second thing,

Coming back to my five. So the second little rule is fermented foods. And this would have been good advice for you on your antibiotics. Trying to get at least three different types of fermented food in every day, even in very small amounts. It can be a little shot. It doesn't have to be a huge portion at all. As well as your yogurt, never go for low-fat, low-sugar yogurts. They're terrible. You've got to go for the natural ones, nothing else in it. Or you've got

fermented milks, the kefirs, or you go for proper cheese that's not in a plastic wrapper, or you go for the 4Ks. So you've got kraut, kombucha, kimchi, which is Korean sauerkraut, and those kefirs. So it's a good way of remembering those things to eat as well. And you can use miso paste of Japanese food is very high on these fermented soy products. So the

There's lots of ways, as well as some Russian pickles and things like this that don't have vinegar and you're making things in brine. And kombucha is everywhere in the US. So that's something that's pretty easy to pick up. Third, I'd go for eating the rainbow and thinking about color and rejuvenation.

the reason is that Carla tells you the chemicals in those plants that are helpful for your gut microbes and the chemicals are called polyphenols and they are rocket fuel for your gut microbes and we used to call them antioxidants before we really knew that they worked via our gut microbes and that's

comes back to the question you asked earlier. So that's a way of spotting them. Really brightly colored ones have the most polyphenols, as do ones that have a bitter taste. So if it's bitter, if it's like tannin, a stringency on the tongue. So things like extra virgin olive oil, many nuts. You've got, again, back to your black coffee.

Some green teas and dark chocolate, even red wine has these characteristics. And number four would be giving your gut a rest. So again, there's time-restricted eating, increasing evidence that if you can leave, you don't have to do massive fasting, but if 12 to 14 hours will give benefits to your metabolism, fire your gut microbes. And finally, it's

switch from eating ultra-processed food to real food. And that means quality, not calories. And I think this is an important thing. Many people still believe that calories are the answer to everything. And we and my colleagues at Zoe are absolutely convinced that

That era is gone. And in a way, as Zempik has shown, all those companies have gone bust now as people have given up trying to calorie count on bad food. And you only have to look around and see, you know, that's been prevailing wind for the last decade.

30 years and it's failed miserably. But if people started selecting food on a basis of quality, you know, without worrying about the quantities, then actually you can lose weight that way as well because you're feeling fuller, your gut microbes are sending off the right signals, etc. So if you remember five things...

about gut health, do that because the food choices you make are most important choices you can make for your health. And these are things we make multiple times a day and very few people tell us, you know, how to do them properly. And you've got to stop looking at packets and labeling and advertising. It's all advertising. There's no such thing as a health

claim on a packet is just fake advertising so people need to get wise and you know reduce from this 60% of the US diet is fake food and we're now getting the science to show why it's bad for our gut microbes why it makes us overeat by 25% why it's been making us so sick

So I love those five. It just really lays out. It gives you a simple, straightforward roadmap for anyone. The one thing that's still an open question in my mind, probiotics. Where are we with that? Well, people always think of probiotics as what you get in the pharmacy or the health food shop in a capsule or magic liquid, but they're in yogurt.

they're in all these fermented foods in often much bigger quantities than you get in these capsules. And you know they're alive because, you know, you can see them, whereas a lot of the probiotics you buy in the pharmacies may contain nothing but sawdust. You know, there's no controls on them at all. So the evidence says that probiotics

do generally work in the trials, but that there's a highly variable response in humans because we all got very different gut microbes to begin with. So it's like getting a transplant with someone else's blood and you're not quite sure what blood group anyone is. It may work, it may not. And they don't seem to work preventively for much. They seem to help people with gut problems to some extent, particularly they seem to work in children, old people, but, you know, well.

But I'm not a big fan of them because I think fermented foods offer the advantage that they're often cheaper and they give you a wider range of microbes. So if you take a homemade kombucha or a kimchi, you're going to get at least 30 different species of microbe. You don't have to pick the one or two or three that you'd get from CVS. It's like night and day, and you don't know those ones are alive or going to do anything for you.

So I think until that science improves and the standards improve, I think you're better off with fermented foods than probiotics. But I'm not ruling it out. And there are studies, there have been other ones on mild depression showing that probiotics can help people. And there's other ones in IBS, irritable bowel syndrome, showing they can be beneficial. So definitely they can work, but it's still quite a crude business at the moment.

It sounds like, I mean, it's fascinating. It sounds like the last decade or so has ushered in almost like it's a new era of focus and research and resources in this area. And we've learned so much. And what you've shared also is that there's still a long way to go in terms of the knowledge base. And it sounds like there is a lot of work now, realizing that this actually matters on a level that probably none of us realized, you know, 10, 20 years ago.

So I'm super excited and you must be incredibly excited to be involved in sort of like progressing that science forward to see what we actually discover in the next 5, 10, 15 years. Yeah, it's one of the most exciting areas in science I can possibly imagine. And switching in a way from academia to working with a...

A company like Zoe that's going directly to customers means that we can get hundreds of thousands of people doing identical studies. And this gives us massive studies that we couldn't possibly afford to fund online.

just out of universities and academia and allows us to make these changes, see these real effects in real time. So, you know, I'm the luckiest scientist around because I get to play with all this stuff. And, you know, you imagine you're 200,000 people and they're all taking the same meal on the same day and you're watching their blood sugars change, their blood fats change, you're seeing how their gut microbes influence that and, you

allowing us to find things like the coffee microbe and all these specific ones, what microbes are going to be important when you eat nuts or seeds, which ones grow, which ones are good and bad. And each of them has some effect like an ozempic, if you like. So I think it's an incredibly exciting field to be in.

And, you know, we're just scratching the surface really of what our gut microbes can do. So I think it's amazing. And people will start testing them just like they test blood pressure. I'm pretty sure that now the gut tests are reliable. This will be something that people will be monitoring. So, you know, when you get to your next course of antibiotics, hopefully you'll have had a gut microbiome test and

You were saying, okay, can I get an antibiotic that doesn't affect these guys? And, you know, what's the doctor going to give me to make my microbes recover quickly? All this kind of stuff, it'll be all linked up rather than, oh, well, that's nothing to do with me. You know, you just take this short term. We'll be thinking much more holistically because the microbes join everything together, you know.

everything from our brain to our body to our energy and so everyone needs to know about them I think that's what's exciting everyone needs to know how to

treat them properly and look after them. They're our friends. Love that. And super excited to see where this all leads as well. So it feels like a good place for us to come full circle in our conversation. I always wrap these conversations with the same question, which is in the context in this container of good life project. If I offer up the phrase to live a good life, what comes up for me?

I'd love to live to 85, doing all the things that I want to do, all the sports, all the intellectual bits, seeing my friends socially. That, for me, is a good life. And living life to its full potential and following my dreams. Thank you. Thank you.

Hey, before you leave, if you love this episode, safe bet you'll also love the conversation we had with Frank Littman about the pillars of health. You'll find a link to Frank's episode in the show notes.

This episode of Good Life Project was produced by executive producers, Lindsay Fox and me, Jonathan Fields. Editing help by Alejandro Ramirez, Christopher Carter, Crafted Hour Theme Music, and special thanks to Shelley Adele for her research on this episode. And of course, if you haven't already done so, please go ahead and follow Good Life Project in your favorite listening app.

And if you found this conversation interesting or inspiring or valuable, and chances are you did since you're still listening here, would you do me a personal favor, a seven second favor and share it? Maybe on social or by text or by email, even just with one person. Just copy the link from the app you're using and tell those you know, those you love, those you want to help navigate this thing called life a little better so we can all do it better together with more ease and more joy. Tell them to listen.

Then even invite them to talk about what you've both discovered because when podcasts become conversations and conversations become action, that's how we all come alive together. Until next time, I'm Jonathan Fields signing off for Good Life Project. My dad works in B2B marketing. He came by my school for career day and said he was a big ROAS man. Then he told everyone how much he loved calculating his return on ad spend.

My friend's still laughing at me to this day. Not everyone gets B2B, but with LinkedIn, you'll be able to reach people who do. Get $100 credit on your next ad campaign. Go to linkedin.com slash results to claim your credit. That's linkedin.com slash results. Terms and conditions apply. LinkedIn, the place to be, to be.