Optimize Your Gut to Fight Disease With Tim Spector

As Hippocrates said, food is medicine. But what food specifically for which person? Under what particular circumstances? And when? Thanks to some astonishing breakthroughs in medical technology, scientists are at the threshold of prescribing food to sidestep disease, predict diagnostic outcomes, promote longevity, and enhance well-being on a highly individuated basis. The era of personalized medicine is upon us. And at the tip of this revolution is today’s guest, Dr. Tim Spector. Arguably the world’s leading authority on the cutting edge of microbiome research, Tim is a globally-renowned epidemiologist and geneticist. He is also the bestselling author of several books, including The Diet Myth, Spoon Fed, and his latest work, Food for Life, an in-depth, scientific breakdown of what and when to eat, and ways we can all improve our own personal nutrition. This is a fascinating conversation that will leave you reframing the importance diet plays in your life—and what the near future holds for better health for all. Show notes + MORE Watch on Youtube Newsletter Sign-Up Today’s Sponsors: Seed: seed.com/richroll ROKA: http://www.roka.com/ Squarespace: Squarespace.com/RichRoll Caldera Lab: http://calderalab.com/richroll SriMu: http://srimu.com/rrp Learn more about your ad choices. Visit podcastchoices.com/adchoices

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:00Rich Roll?

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• 1:18Tim Spector?

  The whole of nutrition advice had been so muddled and confused. It's not about that one thing that you do or you don't do. It's about the holistic view. What can you get on your plate? If three-quarters of it's filled with a giant steak, there's not much room for your plants.

• 1:34Rich Roll?

  Food is medicine. We are now at the threshold to prescribe foods to sidestep disease, predict diagnostic outcomes, and enhance well-being on a highly individuated basis. And at the pointy tip of this revolution is today's guest, Dr. Tim Spector.

• 1:51Speaker 02

  Professor Tim Spector. Professor Spector. Medical professor, Tim Spector.

• 1:54Rich Roll?

  Many consider you to be the leading expert on gut health and diet. Tim is a globally renowned epidemiologist, geneticist, and author.

• 2:03Tim Spector?

  The microbes are these microscopic organisms that build this community in your gut only recently we've discovered are like mini

• 2:10Rich Roll?

  B. Pharmacies awarded the distinction of Order of the British Empire. Tim is also the bestselling author of several books, including The Diet Myth. And his latest, Food for Life, is an in-depth, scientific breakdown on what to eat, when, and why to improve our own personal nutrition. In this episode, we expand upon my many past conversations about the microbiome. We talk about the importance of plant diversity in one's diet. We talk about the environmental implications of food systems and consumer food choices, the future of food, microbiome science, and plenty more. Before we dive in, let's acknowledge the awesome organizations that make this show possible.

• 2:53Rich Roll?

  Okay, right now, let's get into it with Dr. Tim Spector. This one is appointment listening. Enjoy.

• 3:04Rich Roll?

  Well, Tim, it's a delight to have you here today. Thank you for coming. As I mentioned to you a few minutes ago, I've had the privilege and the pleasure of hosting many conversations about the microbiome, about gut health over the years, including the good Dr. B., Will Bolswitz, friend of the podcast, who's sitting right over there right now, who accompanied you. But today is a particular honor because, as Dr. B. insisted I make clear, you truly are the world's leading authority in this field at the cutting edge of all this fascinating, emerging science that's creating a new way of learning about how our bodies work, how

• 3:47Rich Roll?

  they operate in the world, and it's very exciting. So not only are you somebody who's innovating new research, you are also pioneering this fascinating field that I want to learn more about, that we're calling citizen science, which we're going to get into. But I think the best place to begin is just to understand what got you interested in this field, kind of the origin story behind this, and kind of defining our terms with respect to what we're talking about when we're talking about gut health and the microbiome.

• 4:21Tim Spector?

  Okay, well, it's a great pleasure to be here. Big fan of the podcast, so very excited. And my journey's been a bit of a long one, so I... We got time. Plenty of time, okay, so, because I'm old, so that makes one's career longer.

• 4:39Tim Spector?

  I started life as a doctor, went to medical school, and got interested in epidemiology, which is a study of populations. But there was no real jobs in that, so I trained as a rheumatologist, studying bones and joints, and made my way up training in that in London, in medical schools. And on the way, I did a master's in epidemiology. I was still interested in that side of why diseases happen in populations, this sort of detective in me that wanted to find out why things happen.

• 5:17Tim Spector?

  And I, when I did my three years research and my thesis in that whole area, and it was only really after, in about 30 years ago, that I

• 5:35Tim Spector?

  I changed tack from purely rheumatology and I started what's called the Twins UK Project, which was setting up this twin volunteer system across the UK, which now has 15,000 twins in it and has been running out for 30 years. So that was the largest of its kind in the world, where we were intensively looking at these twins as they were getting older and looking at a whole range of diseases. And obviously started with bones and joints, which at the time no one knew much about. And the whole idea of the twin study was this nature v nurture debate. And it was really, really cool time to be doing that because...

• 6:20Tim Spector?

  Many of the diseases we thought were purely due to aging, for example, ended up having a big genetic component. And many things that we thought were genetic ended up not being particularly genetic. So we found that back pain was three times more genetic than breast cancer.

• 6:38Rich Roll?

  Interesting, and also to interject here. You know, the state of science with respect to what we understood about genetics in 1992 is very different than it is today.

• 6:50Tim Spector?

  Yeah, it's hard to believe how much our opinions have changed. And how, you know, the scientists and doctors of the time have had these fixed views about everything was degenerative. It was just, everything was wear and tear. And your body just wore out. And that was a common thing for anything to do with aging. And the idea that there were these big differences between people really wasn't really considered. So it was really quite exciting to be able to write these pivotal papers to disprove a lot of, you know, clinical nonsense that had been talked about. And why some diseases were given more priority than others because they were more exciting,

• 7:34Tim Spector?

  they were sexy diseases, others were sort of dull aging diseases. So that was the time we were living. And it was also just as the sort of genetic revolution was starting, so we were starting at gene markers, et cetera. But it took, the first 10 years was really convincing people that there was a genetic component to common diseases. Up to that point, really only been the rare ones that people had focused on or the sort of exciting ones. So that was a cool time. And I came out of my little field of, you know, osteoporosis and arthritis and back pain into all the other common chronic diseases of aging. And that...

• 8:17Tim Spector?

  Led us to publish all kinds of fascinating work and made me realize that if you had a model that worked, you might as well study all the interesting stuff you can, not be stuck in a specialty like most of my colleagues remain.

• 8:33Rich Roll?

  So from what I understand, I mean, obviously, when you're studying twins, it's fascinating to see a difference in outcomes between two different people that share the same genetic makeup and then trying to figure out like why those, what's driving those, that differential, right? What aspect of their nurturing or their environment is compelling one to become ill and the other one to remain healthy? But was there some sort of epiphany along the way that triggered this fascination that led you into the microbiome? Or how did that kind of evolve out of studying these pairs over so many years?

• 9:16Tim Spector?

  Well, I think I eventually got out of my system that everything was genetic. So I was telling everyone everything is genetic. It turns out that 50% is the average of everything. You name any disease, 50% roughly is genetic. And that got a bit dull because I...

• 9:35Rich Roll?

  It's not a very satisfying answer.

• 9:38Tim Spector?

  No, it wasn't. It was useful because we then went on to find genes, but as it turned out, they weren't that useful either, other than maybe for long-term drug targets and things. But for me, I started looking more closely at why identical twins, who were basic genetic clones and lived the first 18 years of their life completely together, ended up often dying of different diseases. So the aging process was different. There was no real genetic base of longevity. It was very small. One would die of cancer, the other one wouldn't. One would get autoimmune disease, the other one wouldn't. One would be depressed, one wouldn't. So I was starting to intrigue why we were seeing this when, you know,

• 10:22Tim Spector?

  all the previous stuff was showing it was quite, it seemed to be genetic. And yet, the identical twins, which is this perfect model of these, it's like, you know, all of us have this shadow person that can be doing, in a, living in a different environment to us. What happens to them? It's like your own little controlled study. And so I was fascinated by this and I was, I was then determined to try and look and see what were those factors? Was it gene mutations that were different between them? Turned out that wasn't the case. I looked at something called epigenetics, which is where you can switch genes on and off with chemical signals. Did that for a few years. Only small differences that couldn't really explain these big effects.

• 11:04Tim Spector?

  And it was then, it was about, um, yeah, 2000, about just over, you know, 11 years ago that I came across the microbiome and said, let's test this in twins. And that was really epiphany because I found that identical twins had very different microbes. And it was the first time I'd in, you know, 20 odd years of studying them, I'd found something really different in identical twins. And suddenly I said, wow, that's, that's kind of, that is really cool because why should they be different? And yet, if they are different, that could explain why we all get different diseases slightly,

• 11:48Tim Spector?

  what we thought was randomly. Because of this whole new organ in our bodies that is behaving very differently in all of us and essentially producing lots of different chemicals. So I think it was an aha moment, both for realizing, you know, this, what we thought was this randomness of disease. But importantly, also changed my perception about how food works as well. And why that, why in a way, the whole of nutrition advice had been so muddled and confused. And seemingly with poor science. Because we'd assumed everyone behaves the same. Once that food goes into you, you know, it's going to behave the same way in everybody.

• 12:32Tim Spector?

  And suddenly, knowing that even in identical twins, they only share maybe a quarter of their microbes. Means that in response to the same food, they're all going to respond very differently. So that was the theoretical moment when I said, aha, this could be really interesting. I'm going to spend, you know, the next least decade working on this, rather than all these other areas, which I could work on to try and get to the bottom of it. Because I think it can be much bigger than just looking at a few microbes.

• 13:01Rich Roll?

  Right, so it is quite a watershed moment or a paradigm shift to realize or to kind of reflect upon this conventional perspective, which is our genetic makeup is what differentiates us and it becomes this predictor of a variety of things. But in reality, the genetic differences, like we're much more genetically similar than we are different. Right, and that's a very, you know, set number of variables. It's still incredibly complex, but it feels very simplistic in comparison to the diversity of the microbiome and understanding that maybe a better way to look at it

• 13:42Rich Roll?

  is through the differences in, in, you know, these trillions of microbes that are dramatically different from one individual to the next, irrespective of similarities in their genetic makeup. Like, and using that as a lens and then trying to, to sort of wend that or tie that to certain outcomes as a predictor seems like an impossible knot to untie because of the infinite number of variables involved.

• 14:12Tim Spector?

  Yeah, it's, it's sort of mind boggling, the complexity of it. But I think.

• 14:19Tim Spector?

  It's becoming clear that, yes, there are lots of different strains and microbes and, you know, trillions of them, but the thing that does bind them in common is they are essentially mini pharmacies. They are taking food as their sort of consumables and pumping out all kinds of chemicals that are unique to us and our system in completely indifferent amounts. And so there is a certain amount of redundancy in these microbes, but the difference, and I think that the key difference is not so much the microbe, but the products

• 14:58Tim Spector?

  they make, the chemicals. And that's the essential, for me, the big difference is understanding food and nutrition, not as macronutrients or these rather old fashioned ways of looking at it, but in chemicals, that we are converting one set of chemicals as food by our microbes into these other chemicals which have massive effects on our immune system, our brains, and our bodies and our health. And I think as complex as the microbiome is, it can be simplified by understanding those chemicals and this whole science of metabolomics, which is the study of studying these metabolites. So I don't

• 15:43Tim Spector?

  think it's an impossible scenario at all. And luckily, because of the genetic revolution, we have the tools now to measure our microbiome incredibly accurately and actually uncover seventy-five, eighty percent of the microbes that are in there, which is pretty, you know, we wouldn't have believed that possible.

• 16:06Rich Roll?

  Yeah, that's unbelievable.

• 16:07Tim Spector?

  Ten years ago. And the cost has come down from five thousand dollars a sample, you know, to less than a hundred dollars a sample in, you know, in ten years. So it's been an incredible journey and, you know, we're just...

• 16:21Tim Spector?

  Really scraping the surface of what we know about these things, but they have huge potential in all kinds of areas, not just in nutrition, but in pharmacy and fighting disease and everything else because of this, all these incredible chemicals they're producing all the time that we co-evolved with.

• 16:39Rich Roll?

  So before we even go any further, it would probably be good to just define what you mean when you say the microbiome. Like, what are we talking about specifically?

• 16:50Tim Spector?

  In general terms, the microbiome is the term we use for the community of microbes, microorganisms that live in our bodies, and we generally refer to the 99% that live in our lower intestine, our colon. And the microbiome really refers to the genes of those microbes, should technically be called the microbiota, but we just use them as microbiome because I'm not fussy about words and everyone now understands that. So, there are some dispute about how many there are, but they're probably, they're certainly trillions, maybe 100 trillion or so, roughly the same numbers of cells in our body. Most of them are the ones we

• 17:32Tim Spector?

  know about are bacteria, but there are also these other related species called archaea, and there are fungi and yeasts, and there are viruses, five times as many viruses as bacteria that feed off them called phages, which also have a role in health. And there are even parasites that virtually all of us have to some extent in our guts, and some of which turn out to be beneficial as well. So, it's this whole community, a bit like an ecosystem, that is living within us, and it's best considered as a virtual organ. Stick them all together, they weigh about 2 kilograms, same as your brain, and they're

• 18:13Tim Spector?

  basically, as I said, these mini pharmacies pumping out chemicals which send signals all over our body, but particularly to all the immune cells. The majority of which are immune cells are actually lining our gut. And so they interact with those immune cells on a constant basis, signaling whether to be aggressive or be passive and modifying them, tuning them up and down. That helps fight aging, helps fight cancer, sorts out allergies, et cetera, et cetera. Infects, fights infections. And they also produce lots of chemicals that might go to our brain, responsible for serotonin and many other pathways in the brain as well.

• 18:58Tim Spector?

  So it affects our mood and obviously our metabolism and how we digest food amongst others.

• 19:04Rich Roll?

  Right, like so many things, right?

• 19:06Tim Spector?

  Infinite things.

• 19:07Rich Roll?

  But this idea that that our immune system really resides in our gut is kind of a shocking revelation. Like, I always understood that our immune system originates in our bone marrow. And, you know, this is where we're producing all these cells. Yeah, this is why, yeah, this is. And, and, and, and why is it that we didn't begin to really even put these pieces together in a methodical way until, I don't know, the early 2000s? Like, it seems like you kind of got into this around 2011, right? Like, this is all extremely recent. Because prior to that, conventional wisdom was sort of like, you know, we got to get rid of parasites and all this stuff. This is, these are plaguing the human body.

• 19:52Rich Roll?

  And at some point, somebody figured out, like, actually, we're living symbiotically with all of this. And this is crucial to every facet of health. And we're still, it feels like, in the very early beginning stages of trying to understand the true and vast implications of this incredibly complex system.

• 20:12Tim Spector?

  I think it was medical hubris that says that, you know, our powerful drugs can get rid of this stuff. We're fighting the worst of the world. We know that microbes have killed lots of people in history. Infectious diseases, you know, were vitally important. We survived them. Therefore, you know, we can beat them. And antibiotics, sterilizing creams, you know, keeping people away from dirt. This is the way we're going to conquer our sort of our fears. And I think it was a blind spot to realize that the gut health really was important. And for so long, just regarded that the intestine as a tube to get rid of toxins.

• 20:54Rich Roll?

  Right.

• 20:54Tim Spector?

  And that's its only purpose.

• 20:56Rich Roll?

  Absorb nutrients.

• 20:57Tim Spector?

  Some people still believe that, right? But, you know, particularly the toxin bit, but the not realizing it had such major implications as a vital organ for us. And I think it was, you know, few people guessed at it. And even the, you know, you go back to the days of a hundred years ago, Metchinkoff and Pasteur talking about yogurt, they thought it worked because it deputrified the body, you know, got rid of those toxins. They couldn't still imagine that it was feeding other, other microbes inside there. So I think we just had a blind spot to it. Some people believe the Indian, ancient Indian art, you know, understood the, what the sort of core of the gut to health.

• 21:42Tim Spector?

  And so ancient Chinese and ancient Indian did know, but of course, they couldn't see these microorganisms, couldn't grow them. And this has been part of the problem.

• 21:53Rich Roll?

  Right.

• 21:54Tim Spector?

  Medical science just couldn't see them until genetics came along.

• 21:57Rich Roll?

  Hmm. And so over the course of the 30 years under which the Twins UK research has been ongoing, there's been like a thousand research papers that have come out of this. What are some of the revelations that have emanated out of looking at twins through this lens?

• 22:18Tim Spector?

  Oh, it's hard to pick highlights. I think, because there were some revelations at the time, they seem, might seem rather dull now. Like I was saying, you know, back pain is highly genetic, might not surprise people now to say, you know, but other ones were, one of the first to look at.

• 22:36Tim Spector?

  Fat distribution was highly genetic. So whether, when you put on weight, whether you accumulate it in your belly or your bum, really strongly genetic, and you can see that in families, it's sort of obvious. We showed for the first time that cataract wasn't just, was something you inherited as well. We looked at early risk factors for melanoma, found that, because everyone talks about melanoma, they're always talking about sunshine, which is a really overrated risk factor for melanoma. It's actually highly heritable about whether you have these lots of moles.

• 23:16Tim Spector?

  You have light skin and lots of moles, much stronger genetics than anything else. And so you can divide people into those groups. And twin studies helped us with that. And we did sort of fun stuff. We found sense of humour wasn't particularly genetic. Political views were. So your right wing views or your left wing views have a kind of strong heritable basis. Interesting. As does belief in God have a heritable basis. So there's nearly anything that you can quantify, you can study in this way.

• 23:58Tim Spector?

  If it's, if you can quantify it reliably and get the similar answer. So it allowed us to look at sexuality as well. And we were the first to look at the genetics of female sexuality. So you can study any personality or trait in that way, as well as things like the microbiome, epigenetics, which again has some genetic influences, and even things like vitamins. So people are always talking about, oh, my vitamin D level is low. Well, We were the first to show how that was strongly heritable and that there are certain genes.

• 24:39Tim Spector?

  So 50% of the differences between, say, our vitamin D levels are going to be due to differences in our genes. So what's normal for you isn't going to be normal for me.

• 24:49Rich Roll?

  And how does epigenetics play into that? From my understanding, epigenetics basically means the potential for genetic expression. And also, this idea that we're kind of storing genetic information passed on from our ancestors that is perhaps latent, but given the right set of circumstances, could be expressed. Like, how, you know, that seems like a sticky wicket and very complicated to kind of understand. And there's a certain aspect of it that's sort of mystical in terms of like, the inheritance of ancestral trauma and things like that.

• 25:31Rich Roll?

  Like, how does that play into how you think about this and study populations?

• 25:35Tim Spector?

  Well, I wrote a book about this called Identically Different, which nobody read, but I think it was a great book, but, you know, as often the way. And went into a bit of this and a bit theorizing about it. And it's been called soft inheritance. So it's an inheritance, we think it's an evolutionary adaptation that allows, in times of stress or famine or some emotional stress, to just switch the genes on or off in a way that takes you on a different path, to some extent. And the general belief is that it takes so long to change your genes normally, that,

• 26:18Tim Spector?

  you know, your whole family would have been wiped out by that time you'd made that switch. But if this allows you to, I don't know, there's a temperature change, so allows you to switch, so you gain more weight, or just the fact that your family might all be switching their genes so that they end up more different, they're not all going to be wiped out by the same environmental stress or infective agent, makes some sort of sense. So, but it just lasts for a couple of generations and then fizzles out. So. When I was looking at it, I did interview lots of identical twins who went through stress, for example. And it was quite remarkable that, say, you know, a very major family breakup or something

• 27:02Tim Spector?

  when the teenage twins, one, for example, responded by overeating and got very obese and the other one had an eating disorder and ended with anorexia. So they were acting in response to a stress, but very differently, probably because the, in theory, you know, the genes were switched and doing something, but there was something in our, there's something in our evolution that allows us to have these switches and make you depressed or happy and these things. So I think in response to stress, it does make some sense. And there are lots of stories about after the war, Dutch hunger famines, whole populations

• 27:46Tim Spector?

  having these stresses, which for several generations had effect on their mental health or others due to these change in genes. So it's a lovely, it's a nice theory, but it's been really hard to prove it in humans. Mice sort of works quite well, is often the case. And you can change mouse hair color, for example, just by giving them different vitamins and things, switching them epigenetically or giving them alcohol or whatever. Can't do that in humans, so.

• 28:15Rich Roll?

  It's gotta be so frustrating to see, you know, amazing kind of dramatic results in mice studies and not be able to replicate that in humans. I mean, that seems to be kind of like the recurring theme across all areas of science.

• 28:28Tim Spector?

  Millions of scientists have been frustrated and they say, that's why I didn't get that Nobel Prize, you know, that's, humans just don't behave like mice, it's very annoying.

• 28:38Rich Roll?

  Right, and the mice studies are what, you know, generate a lot of hyperbolic headlines in terms of breakthroughs and creates a lot of consumer confusion and.

• 28:45Tim Spector?

  And they still do, and it's similar in the microbiome, it's not very, it's not different and there were, you know, some misleading studies in the early days of the microbiome that just.

• 28:58Tim Spector?

  Exaggerated the potential effects in humans. So they were, you know, I think they were accurate, but they just, from mouse studies, you can't really get an idea of the scale of the effect in humans. Hmm. You don't know if it's trivial or it's really large. And I think that's the other sort of problem about extrapolating. And, you know, we're not, we're not rodents and we have very different lives and we eat different things. And so, yeah, more and more, you know, we realize that a lot of these mouse studies were flawed. And of course, you can do unlimited number of mouse studies. You know, you've got labs, well-funded labs, they can afford to slaughter thousands of

• 29:41Tim Spector?

  mice and they don't necessarily report every experiment they do. Right. And that's the other problem, which human trials, they take so long to do. You, you know, whether it failed or not, you're going to write it up because it's, it's important.

• 30:03Rich Roll?

  So you're starting to develop this, you know, growing sense that the microbiome is, is, is playing a much more crucial role than, than previously imagined. And, and, you know, this sort of leads you into the American Gut Project and the British Gut Project. So talk a little bit about like how that came together and, and what that was all about and kind of what you discovered as a result of that.

• 30:29Tim Spector?

  Well, so when, back in 2011, there was no one really doing microbiome research in the UK and most of it was going on in the US. So I got in touch with a colleague who I met at a meeting, Ruth Lay in Cornell, and we, we did all the microbiome testing in her lab there. And she was linked with this group that had all worked with this, really the, the father of the microbiome, Jeff Gordon, and who based in St. Louis. And Rob Knight was another one of his proteges and.

• 31:07Tim Spector?

  He learned that I was really interested in this and I was doing the big twin study and told me about his project which he just started, the American Gut Project, which was a citizen science project, getting Americans to sign up, basically donate money in order to pay for their own microbiome testing. And I said I was really keen on doing this in the UK and I think we could, you know, British public were up for this as well. And so we got together and under the banner of the American Gut Project and did this and led to a paper where the UK Ang provide about a third of the subjects.

• 31:49Tim Spector?

  So relatively it was more popular in the UK, given the population density. But together we did a great paper which How many were in the study? There were about 11,000, I think it was, in the end. Which doesn't sound much at the moment, but it was the biggest study done to date. Clearly showed a link between nutritional eating habits, fibre and health and showed that these clusters, that, you know, measures of gut health, which is then we used something called diversity.

• 32:32Tim Spector?

  The more diverse the species, the healthier you were and the less likely you were to obese or have diabetes. And so this was common to the British and the American populations. American populations tend to still be, they were slightly heavier, slightly less diverse microbes compared to the British. But the key bit of that paper was it was the one that found that 30 plants a week was the sweet spot for maximum diversity. And that study still hasn't sort of been bettered many years later. And it's been a bit of a mantra for me in the books that I write for the public about

• 33:16Tim Spector?

  trying to educate people about what to eat. And I think what was really important about the study is that it showed as long as you ate 30 types of plant, and that's including nuts and seeds and

• 33:31Tim Spector?

  To some extent, herb mixes and spices. It didn't matter whether you had a little bit of meat, a little bit of fish. You were vegan, vegetarian, whatever. Your gut health was still optimal. And I think that still resonates with me that it's not about, you know, that one thing that you do or you don't do. It's about the holistic view of that. What can you get on your plate? Clearly, if you've got a big, you know, if three quarters of it's filled with a giant steak, there's not much room for your plants.

• 34:04Rich Roll?

  Right, so the top level rule just being diversity of plant life in your diet on the most consistent basis possible is producing the diversity in that gut microbiome ecology that is going to be, you know, the sort of front lines of keeping you healthy.

• 34:24Tim Spector?

  Yeah, and it's a nice, simple rule that means you don't have to be too strict about

• 34:30Rich Roll?

  Right.

• 34:30Tim Spector?

  anything else, because if that's your number one rule, then everything, you know, follow. Yes, it's nice to have, you know, the rich, colorful, polyphenol-rich foods. It's nice, you know, the fermented foods we know are good as well. Avoiding ultra-processed foods, et cetera. But that, to me, is still number one. And I think that's been a good, you know, a really good way of communicating it also to the public about understanding. Why want to feed your gut? Why feed your gut microbes? You do it by eating right. And if you do that, you know, you can't really have ultra-processed food. It's very hard to get.

• 35:12Rich Roll?

  You're crowding it out. Yeah, you're crowding it out. Yeah, I mean, and it's an easy rule to follow. It's flexible. It's doable. It's easy to wrap your head around what that means. And it's withstood the test of time because that project was like 2014, right? When you were doing that? So I'm curious about how that was received at the time? Like, we're all talking about the microbiome now. Was that the case back then? How were your colleagues sort of, you know, receiving this pivot in your career and this focus on this new science at a time where this was just emerging?

• 35:49Tim Spector?

  Well, it didn't have any of the public impact that it has now.

• 35:52Rich Roll?

  Mm hmm.

• 35:53Tim Spector?

  So the newspapers-

• 35:55Rich Roll?

  But they weren't like, "You're a nutter, like you've gone off the reservation."

• 35:59Tim Spector?

  Well, I mean, there was awareness in 2014, people, it wasn't like, you know, people were talking about the microbiome, there wasn't interest then, not like now. There was, but a lot of people thought it was a passing fad.

• 36:12Rich Roll?

  Uh huh.

• 36:12Tim Spector?

  But like a lot of these new science, you know, as soon as something comes up, a lot of grants follow it, money goes there, it's hyped up because you write a grant to hype it up, that's how you get your money, and then it all comes crashing down again. And a lot of people thought that the microbiome was, you know, just a few years, flash in the pan, a few fancy mouth studies, you know, there's a few anecdotes of fecal transplants that were successful, it would all fall over. And most of my colleagues in the UK were not keen on it at all. And so countries varied about whether they supported it or not, and the UK certainly didn't. And that's because a few powerful people in science just said, "This isn't going to work. It's rubbish.

• 36:57Tim Spector?

  We've got to stick with genetics, it's the only way." And also the nutrition, the nutrition sort of profession didn't embrace it at all either. They felt threatened by it and didn't approach it. So pretty much on my own, doing this, often with US collaborators or overseas collaborators, and getting maybe commercial money, and we used the citizen science funding actually to get a lot of our work done, where we asked the public to actually pay for our research.

• 37:33Rich Roll?

  Hmm.

• 37:33Tim Spector?

  And that really got it going. So that was, that was really where we were, you know, up until the time when I realized I wanted to do the next stage, and I was giving a talk about the microbiome, and that's when I met these two guys, came up to me and said, "We'd like to form a company." And with all the trouble I'd been getting, getting money academically, I said, "Aha, this could be my, my big chance." But-

• 38:10Tim Spector?

  You know, I'm warning you guys, you know, the science is very expensive. And there's no quick results, you know, the way I want to do it, I don't want to do a marketing led project with, you know, smiling M Ds and a stethoscope on the front page. It's, you know, it's got to be serious science, it's going to cost you several million before we get going. So I thought I'd never see them again, but they came back a few weeks later with the money. And so that's where the company Zoe was born.

• 38:39Rich Roll?

  Right. And the kind of operating principle behind that and the studies that you wanted to pursue were what specifically at that time?

• 38:48Tim Spector?

  Well, we wanted to really test the idea that you could use the microbiome and other blood tests to personalize food choices and nutrition. That there was sufficient variability between people that you could use that to predict everyone's response and so give people a real idea of what they should be eating. And came out of this idea that, you know, there isn't one single diet that suits everybody.

• 39:26Tim Spector?

  And all these studies like that of Christopher Gardner, the Diet Fit study where, you know, they competed high fat versus high carb diets. And both did well, no winners or losers, but within the groups massive differences. So, and at the same time, an Israeli group had come out with a study showing that CGMs, continuous glucose monitors, were able to also predict responses to food. So suddenly the idea was there to combine the microbiome with these, these new devices

• 40:09Tim Spector?

  on the market to suddenly have a quantitative way of really telling people how they respond to these foods. And, but the only way to do that wasn't in theory, was to actually do a really big experiment to prove it and see if it worked. So it was a big gamble at the time.

• 40:24Rich Roll?

  Right.

• 40:25Tim Spector?

  But luckily managed to convince these guys it needed to be done. And the study was a thousand people, giving a thousand people, mainly twins, because I still believe there was a genetic component then. And who were studied at my hospital, St. Thomas's, and a group were also studied in Mass General, given identical foods at the same time, and then all their bloods studied, you know, and work up for 24 hours and then for two weeks onwards. And it was that experiment, which was the largest of its kind, that really was the basis for everything else we've done since then.

• 41:10Tim Spector?

  And that was the PREDICT study.

• 41:12Rich Roll?

  Right.

• 41:13Tim Spector?

  And that, you know, that as well, that gave us the next revelations, if you like. So having known that the microbiome was different between people, there were two other big aha moments there when we first looked at the data. One was when you give people an identical muffin, there was at least a tenfold difference between normal people's response in sugar and insulin to that muffin at identical time of day in laboratory conditions. So that was, well, pretty amazing. There was also a tenfold difference in their triglycerides, their blood fat levels, six hours after that meal. So everyone clears fat at a very different rate.

• 41:55Tim Spector?

  And up to that point, no one had ever thought to even look, because we only take fasting levels, which aren't very informative. And that really meant that we had the basis of a big enough variation to build algorithms to predict how people would do based on those sort of baseline standard tests.

• 42:17Rich Roll?

  Right. So it provides this like sort of starting base to try to begin to understand the nature of personalized nutrition and lifestyle habits and the variations, you know, between people and how those, you know, certain variables that distinguish individuals.

• 42:40Rich Roll?

  Can be valuable information in terms of how people respond to certain foods or don't. And when you start to scale that up with massive data sets, you can extrapolate from that valuable information to provide solid guidelines in terms of do's and don'ts. So that gets into the citizen science aspect of the conversation that I want to get into. But there are so many things in what you just said that I want to tease out gradually. The first being just the realization that gut health, the microbiome in so many ways, holds this key to unlock so many things that have befuddled scientists for so long.

• 43:24Rich Roll?

  And there are a few things as complicated as nutrition, and certainly it's something that is so hotly debated and it appears that it's so difficult to arrive at any kind of consensus around. And you talk about this in your books. But what's really empowering and fascinating about the microbiome is its mutability. When you look at genetics, you come with a, this is your DNA, this is your genetic makeup, and you can say, well, my dad got this, or my grandfather got this, I have a genetic predisposition to this. And perhaps there's some mutability around the epigenetic piece, but there's not that much that we can do about it.

• 44:07Rich Roll?

  But with the microbiome, there is this mutability, and trying to understand how to maneuver around that mutability and push it in certain directions becomes the vanguard of this whole new horizon of science and discovery.

• 44:23Tim Spector?

  Yeah, for me, it was a revelation because I was a geneticist. I'd been finding genes, I'd been telling everyone that it's all a genetic basis. Just blame your parents for everything.

• 44:35Rich Roll?

  You're eating crow now.

• 44:37Tim Spector?

  And hope that, as you said, take this magic potion to tweak your epigenetics, and you've got a chance of doing it. But it was a pretty depressing talk, and I was getting myself down a bit about it. And so it was so... Empowering really to realize that, yeah, identical twins have very different microbes and they respond differently to the same foods. You know, we had these identical twins. One would have a good fat response, the other a bad fat response. And the only thing we could find different was their microbes. So the fact that, you know, other studies before us, you know, this study, some amount of UCSF had shown just by changing from vegan

• 45:22Tim Spector?

  to meat eating diets in four or five days, you can switch your gut microbes. You can do this stuff in a few days. So unimaginable to change your genes in that way. So I think suddenly, you know, me personally, I was really energized to say this is really important and that small changes to your nutrition can have massive effects, you know, via your gut microbiome if we get it right. And so everyone needs to know much more about gut health and the microbiome and treat it, you know, just as you would look after it like you would your heart.

• 45:57Rich Roll?

  Right. And getting it right is hard. That's a, that's a big, hard problem, right?

• 46:04Tim Spector?

  Well, we were starting from, yeah.

• 46:05Rich Roll?

  It's a different, yeah, it's like this, I feel like you're kind of cresting this hill where for many years it's been about trying to understand the nature and the complexity and just the general landscape in which the microbiome operates. And now we're in this kind of transitory period where it's about applying that understanding into kind of tangible, you know, protocols or, or means of, of diagnosis and, and recommended therapies.

• 46:35Tim Spector?

  Yeah, no, it's, it's, um, uh, it's tough. And I think we mustn't.

• 46:43Tim Spector?

  You know, again, realize that we know more than we do. And so we are just at the tip of this discovery. You know, the microbiome sequencing is is just getting to the point now where we're discovering all kinds of new elements to our gut microbiome. Like, you know, we've discovered this parasite that's in one in one, you know, one in four British people have this parasite called Blaster cystis. And it's only in one in 20 Americans.

• 47:10Rich Roll?

  Hmm.

• 47:11Tim Spector?

  And we've and if you have it, if you went to see your GP, he'd probably say, look it up and say, okay, we've got to get rid of this guy. You know, it's been shown to cause diarrhea and bloody, you know, problems and whatever. You know, better kill it, let's get it out. But it turns out that if you've got it, you are healthier, you've you're skinnier, you've got less visceral fat, your blood lipid levels are lower, your blood pressure's lower, and it's a sign of super good health. And it's, you know, and so we're discovering that this this parasite actually probably

• 47:53Tim Spector?

  eats other microbes that are increasing your fat levels. So it's sort of

• 47:59Rich Roll?

  Wow.

• 48:00Tim Spector?

  It's a sort of predator of other microbes that we still don't understand which ones and having this effect. So and it turns out all our ancestors had this Blaster cystis parasite. And if you look at all the data, whether it's modern day, you know, hunter gatherers or most third world countries, 100% of the populations have Blaster cystis. And modern living has wiped it out.

• 48:25Rich Roll?

  Hmm.

• 48:26Tim Spector?

  And, you know, we even see big differences between, you know, Midwest America and California. There's, you know, where healthier people are, it's a sign of healthy diets and healthy living. It's it's fascinating. This is just one element of all these other, you know, we know nothing about the fungi, the parasites, the viruses, the phages that are doing this stuff as well. So let's, you know, we can't get ahead of ourselves. We've got to stick to the basics as we as we learn and understand that. You know, we're all got different makeups and different bugs inside us that could be doing different things.

• 49:03Rich Roll?

  Right. The insane complexity of all of it seems like a perfect dynamic for introducing the tools of, the emerging tools of artificial and of artificial intelligence because they're so good at crunching massive data sets and, and dealing with, you know, complexity at this kind of scale. Has there been any inroads with these, these kind of emergent tools and how they might apply to this field?

• 49:33Tim Spector?

  Well, we've, we think we've just about got to the level. So we've now got, we've been looking at our latest paper at 50,000 stool samples from the US and the UK. People have taken the Zoe tests. And with those numbers, that's, that's, that's where you start to get this real power. And so we're just starting that journey now to try and understand it and link that with our health outcomes. But in a way, we are, we're doing this on a small level with our, with our studies at the moment. It's allowed us to work out what we think a healthy microbiome looks like in most people. So what's the sort of key ingredients of a healthy microbiome, which has been quite elusive.

• 50:18Tim Spector?

  So we, you know, we've got a list of good and bad microbes that's getting bigger and bigger that we find if you get that ratio right, that's, that's

• 50:27Rich Roll?

  Right.

• 50:28Tim Spector?

  That's associated with all these good health outcomes and associated with these healthy foods as well. So it's the link between the foods, the microbes and the health outcomes.

• 50:39Rich Roll?

  Right, right, right, right.

• 50:40Tim Spector?

  But you need these big data sets, you know, like we did in genetics before you really start to get the clues out. You know, if you're dealing with just hundreds of people, it's just We have too much variation to be able to deal with it.

• 50:52Rich Roll?

  Right, and those big data sets introduces this idea of citizen science. And I want to get to personalized nutrition, but I don't think we can really talk about that until we kind of discuss the impact and the potential impact of what this whole emerging world of citizen science is and the kind of advent of these technologies by dint of Zoe and other kind of things that are out there that are allowing you to run incredibly detailed experiments at a massive scale unprecedented in the history of science.

• 51:35Rich Roll?

  Because Will and I were chatting the other day and he was telling me like, listen, in testing or in science, historically, you can have a small population of people that you kind of control and you can get very detailed information out of them, or you have population studies that are very general and basic because you lack that level of detail and control. And now, because of these technology platforms and in particular what Zoe is doing, you can get both, you can get the best of both, right? Which opens up a whole new world of data analytics and the power of the results that

• 52:15Rich Roll?

  you're seeing to create predictive outcomes and again, like diagnostic tools.

• 52:21Tim Spector?

  Yeah, no, I think it's a real game changer in science because in a very short period of time, we've built up the largest microbiome database in the world. We're now doing microbiome sequencing on two and a half thousand people a week and doubling that very soon. Because in a way, people are paying for those tests themselves and they're all signing consent forms to say they agree to share that data for science so that, you know, it's not just lost as it would be in any normal medical clinic or private facility or whatever. So it's all going back into a large database that we, you know, we've

• 53:03Tim Spector?

  published, I think Zoe's published like forty papers now on this kind of data. So it is a whole new phase, I think, of science. So rather than waiting five years to get a NIH grant or, um, so slow, you can do this in real time and get these results back. And I think my eyes were open to this, um, you know, we'd started Zoe, but then a pandemic hit and, um, twenty twenty and obviously everything, all our clinical studies stopped

• 53:40Tim Spector?

  on the twins. And so whilst cycling home from, in London, I had the idea of, uh, asking, repurposing the, the sort of Zoe app, which was based for nutrition, to understand COVID and get COVID symptoms, et cetera. So it was a bit of a wild idea, but the, my colleagues, George and Jonathan, loved it, the whole company loved it. And so in five days, we built this app, which, um, went live, totally raw, full of bugs, you know, and thought it would flop, but at least we'd done our bit. And we had a million people download it in twenty four hours. So one of the biggest sort of health. How'd you manage that?

• 54:24Tim Spector?

  Social media. Everyone shared it. So this is a great idea. It was the first day of the lockdown in the UK and we launched it a week later in the US. And within two weeks, we had two million and then we eventually got to four million people using this app at a time when there was.

• 54:46Tim Spector?

  People wanted to unite, to do something. And the government was useless. You couldn't go and see your doctor, you know, you were told to stay at home. You couldn't get tested, so it it just struck a chord. And we were told no one over sixty is going to use an app, right? That was the other thing they say, well, you know. Technology is not for oldies, you know. They have to, you've got to send them a webpage or, you know, or a questionnaire. Prove that wrong, you know, we had people in their nineties doing this. And it it absolutely took off and so it became the number one tool in the UK for knowing where outbreaks were happening and what was going on.

• 55:29Tim Spector?

  And we learnt also what the new symptoms were, which were not what we were told from the original Chinese variant. And so just in real time, we were seeing as people reported on the app, rather than old fashioned science of questionnaires and, you know, waiting a year to validate the paper and whatever. In real time, we we got a system worked out with the team at Zoe so that we knew that

• 55:58Tim Spector?

  loss of smell, for example, was being reported by, you know, a third of people who had, you know, had all these other symptoms of COVID or tested positive.

• 56:08Rich Roll?

  Right, so that's the origin of of how it was determined that loss of smell was the thing, right? It came out of that originally.

• 56:16Tim Spector?

  Clinicians noted it in Italy. So they were saying, it's strange, I've got, you know, ENT people were saying, I think this seems, something must be happening here, but they couldn't tell. Couldn't do a proper study, so it was a combination of having that real data in millions of people. And we presented it and, you know, suddenly WHO and all these other countries around the world changed their criteria. It was the UK was the slowest to change, but interestingly, because they they hadn't done the study themselves, but that was that was a wake up call about how fast this new way of doing science with new technology, with apps, citizen scientists working together could do so much.

• 57:01Tim Spector?

  And we did lots of other stuff that I'm really, really proud of the the team for doing. As well as the other symptoms, we found delirium in old people was a sign. Children got very different symptoms. We we looked at skin. We we asked people to send pictures of their skin rashes with COVID.

• 57:19Rich Roll?

  Mm hmm.

• 57:20Tim Spector?

  I think we got thirty thousand pictures.

• 57:22Rich Roll?

  Wow.

• 57:22Tim Spector?

  Um, and she formed an atlas that, you know, people could see around the world. Um, we, um, there was some COVID tongues. So people were sticking their tongues out, taking pictures, you know, and suddenly people felt engaged for the first time they were doing something. And I think it was really important. We did a study that would have taken, you know, five million dollars and five years to do where we we asked a million people to fill in a diet questionnaire um in the U S and the U K and and look to their severity of COVID they got, you know, a year later.

• 57:59Rich Roll?

  Hmm.

• 57:59Tim Spector?

  And with that data, we clearly showed that diet quality was one of the biggest factors in determining uh how you were likely to die or to stay in hospital, have really serious COVID, a link with the immune system and nutrition. So this is all done at the speed of light. We were writing papers in a few days.

• 58:24Rich Roll?

  Yeah, shocking. I mean, so four million people, how many people are on the app now?

• 58:29Tim Spector?

  Uh, we have about, there's still about three hundred thousand still logging uh daily and we've, but we've, it's so it's three years on now. Um, it's obviously come down from the millions that were doing it. But we've repositioned it um into a health study app. So we've we got consent to study more than just COVID. And we've now using it to do other lifestyle factors. So we realize that it's potential. And so um we, for example, have just finished a study on intermittent fasting. So a hundred and forty thousand people to.

• 59:11Tim Spector?

  Agree to change their method of eating to eat in a time restricted eating window of 10 hours. And we repurposed the app and gave them so they could fill this in and tell us how they were doing in terms of their mood, their sleep, their appetite, their weight, any other factors we wanted to. And got this launched really fast. And amazingly, most people, and they could do the fasting whenever they wanted. So we were also looking, it's a way of looking at not just does it work, but how practical is this? Because you have these tiny studies done on 10 people. Handpicked volunteers from Stanford.

• 59:56Tim Spector?

  I mean, what can you really extrapolate from that? They're not generalizable. Yeah. So it was really cool to see how many people managed to do it. And I think it was about 80% or something managed to do it for at least three weeks, at least five or six days a week of just eating in a 10 hour window. And we're still writing up the papers, I can't give you all the details, but it was super encouraging because the people that did manage to do that 10 hours reported all kinds of benefits on some of their GI health, many of them were less bloating, mood improved. And interestingly, appetite didn't go up. Because we're all told, well, if you...

• 1:00:40Tim Spector?

  And there were differences between men and women, differences in different ages. But the fact we could do this massive study at very little cost in such rapid time really means, for me, this really is the future of how we can particularly do subjects that don't get the funding. You know, the sort of studies about who's going to give you big money to do meditation or yoga or five minutes exercise or going to bed earlier or, you know, cutting back on alcohol or, you know, just seeing what are the practical cold showers, you know,

• 1:01:25Tim Spector?

  who knows, you know, these things? You get... You know, you get the aficionados who tell you, yes, you know, the dedicated guru say, if you do this, it always works. All anecdote. What about the real, you know, the person on the street? How good, useful is it for them? How easy is it to do? Fascinating that people, you know, because we're told like intermittent fasting works better if you, um, you, you do your fasting later at night. So you don't eat after, say, 5pm, right?

• 1:01:57Rich Roll?

  Right, right, right. Yeah, like that 10 hour window. When is that 10 hour window? And what are the age of these people? And what are the foods that they are eating when they break their fast? There's all kinds of variables. And then beyond that, there's adherence issues. And are these people even being honest with what they're reporting?

• 1:02:13Tim Spector?

  None of these things are useful if you can't adhere. It's like diets, right? Completely pointless if you can't stay on it long term. So finding out that, you know, only about a quarter of people in the UK prefer to, to do their fasting late at night. I, you know, have an early meal and then, uh, most people, it was easier in their lifestyle to like delay or skip breakfast. And that's just really useful to know that saying, well, actually for most people, even if it's not quite as good biologically, they can keep, probably keep that going for years. So it's much better rather than this purist idea that this is the only thing that people should do.

• 1:02:53Rich Roll?

  Right. Like what's, what's replicable and sustainable? Uh, yeah. And if you do that, then are you eating at, you're, you're probably eating dinner at six or seven as opposed to 10 at night? And what's the implications of that? But the real power, it seems, comes in when you, when you layer on top of that, all kinds of other, uh, sort of biometrics from heart rate variability, the, the, the glucose monitor that's showing how you're metabolizing, you know, your food, um, resting heart rate, you know, metabolic rate, all these things with these, you know, kind of devices now that all, you know, establish a matrix of variables that

• 1:03:35Rich Roll?

  you can then compare and contrast to draw, you know, a more kind of intelligent conclusion from just, I feel better or I slept better. But well, actually, if I look at this, you were, your deep sleep number increased, or your REM went up, or it went down.

• 1:03:51Tim Spector?

  Yeah, I think that's the next phase. That's the next phase, I think, is to, having shown this works at a sort of crude level. Is to try and get people to input, you know, either automatically or semi-manually, some of these inputs and then rework some of this data. And we want to also, with people doing the Zoe, the paid Zoe program, also start having some of these interventions as well. So that, you know, every wave, a different week, might do a different intervention. So we can actually see, well, can you personalize some of these lifestyle things well? Can you predict who's going to do better? Is there a certain cold shower person? Is there a

• 1:04:33Tim Spector?

  certain early fasting person? Can you predict who they are as well? So I think the more you can combine these things together with these interventions as opposed to just observation, the more you can do it. And everything we've seen is people are super willing to take part. And even if they've been paying money, they like the idea of being in these large experiments, as long as you give them, you feed back the data. So in the past, researchers like myself have been grabbing all the information you can. And then five years later, you get a little, you know, a note saying, thank you, we published it in Nature, you know, you probably forgot what it was.

• 1:05:12Rich Roll?

  Right.

• 1:05:13Tim Spector?

  Thanks for your help. Now it's very much, you know, you've done the study, people want to know how they got on, how they compared to other people. And it's, this is what we have to start to do much better than we've done in the past. But I think it's, I think it's really exciting. I wish we'd discovered this 20 years ago.

• 1:05:31Rich Roll?

  Well, these things happen.

• 1:05:32Tim Spector?

  Wouldn't have been possible.

• 1:05:33Rich Roll?

  Yeah, the technology has to, you know, be robust enough, right? And I, you know, to your point, we are at the very beginning of this. I mean, I think there's, you know, there's privacy concerns, there's other kind of issues that need to be kind of properly navigated. But it is exciting. And I think it answers a critical question that, that I'm sure gets posed to you from your critics around like, okay, so you're making these breakthroughs and you're trying to understand, you're understanding better what's happening with the microbiome, et cetera, and everything that's going on, you know, on your platform. But like, why does this matter? Like, how are we translating this into anything actionable?

• 1:06:16Rich Roll?

  Like, what is the reality of personalized medicine versus the promise or the hype?

• 1:06:24Rich Roll?

  You know, how close are we to kind of bridging that gap between our aspiration and, you know, what we're actually capable of providing, you know, the interested consumer?

• 1:06:39Tim Spector?

  Yeah, there's plenty of critics of personalized nutrition, which is what we're into, as opposed to medicine. I mean, because that's, in a way, the personalized medicine has been discussed before, particularly with regard to genetics and genetic testing and things like that, and selecting drugs on a basis of those things.

• 1:06:57Rich Roll?

  Remember the blood type diet?

• 1:06:59Tim Spector?

  Yeah, exactly. A fantastic example, that's right. So, there's been a lot of rubbish.

• 1:07:05Rich Roll?

  Yeah.

• 1:07:06Tim Spector?

  But the new area of personalized nutrition, A, we've published, you know, peer-reviewed papers in Nature Medicine, you know, high-quality journals to show there are these big individual differences that are real. We have performed a randomized controlled trial of unpersonalized approaches, you know, standard US advice versus people doing the Zoe program. We haven't unblinded the results, but I'm looking at it, I'm very confident they're going to be good. So, the randomized controlled trial is the best way

• 1:07:48Tim Spector?

  to tell whether it's better than, you know, uniform advice. And I think the other reason is that as soon as something's personalized to you, you're much more likely to take, believe it. I think that's what we've shown in all of these, all these citizen science ideas, that if you can make it, this is your response, it's not just the average response. It's not like everybody, you know, who goes on this diet does well. We know that you respond to this, you will do it. So, your adherence to it is much more likely, your level of belief is so much higher. And if that's backed up by science, then...

• 1:08:31Tim Spector?

  I think, you know, it's inevitable it's going to happen. So these critics, yes, we need to do these big studies. We need to do the randomized controlled trials. These critics are generally, you know, hanging on to the past and old style nutrition. And they will be dropping off. This is absolutely the the future. And I think, you know, yes, we won't be able to sort out all the problems. You know, we're a long way from, I don't know, working out exactly how much protein every individual has because we don't have ways of measuring protein response in the body and things.

• 1:09:08Tim Spector?

  But, you know, for for glucose and for lipid levels and and assessing how much those people need, I think we're we're doing a pretty good job now. So and, you know, I think the studies will show that people feel better. Anecdotally, the people were saying they felt better and the randomized controlled trials actually are saying saying the same thing. And I think the bit we've always been forgotten about nutrition, which we didn't know, is things like energy. It's never really been asked before in nutrition trials, you know, what's your mood and energy like when you change from, say, a high fat or a high low or, you know, whatever it is

• 1:09:52Tim Spector?

  you switch around to something that suits you and you don't get these spikes in your sugar or you don't get this, your triglycerides hanging around your body, which means you get less inflammation. We're seeing that in everything we do is this this report of I feel more energy. Right. And I think that's that's that's really important. So it's not just about weight and, you know, the the sort of external stuff. It's it's finding out what foods make you feel good. And, well, you know this from running, you know. Yeah, of course, of course. People do this by trial and error. Yeah. That the average non-sports person has to rely on other tricks to do it and may not have thought about it in the same way as a performance athlete.

• 1:10:42Rich Roll?

  One of the diagnostic tools that you're using for this is the continuous glucose monitor. And that, you know, I want to talk more broadly about metabolic health in general and how that relates to the microbiome. But with respect to CGMs, there's a lot of squabbling around that as well. There's a certain kind of subset of the type 1 diabetic community that seems unhappy with the fact that this is available to consumers more broadly. And, you know, I believe that that comes from perhaps an affordability or access perspective. There's another kind of contingent of people who don't like it because they think that

• 1:11:23Rich Roll?

  an undue fixation on CGM metrics alone paints, you know, an incomplete picture of what you should or should not be eating, et cetera. And there's, you know, kind of the whole biohacker community around it that's drawing conclusions that aren't necessarily completely solid because of an over-reliance on that variable over kind of a matrix of complementary values. So can you talk a little bit about the benefits and perhaps the limitations of the use of a CGM? Like, I've used it. I found it to be super interesting. I drew a lot of, you know, kind of non-intuitive conclusions about my lifestyle habits and

• 1:12:08Rich Roll?

  certain foods that were contributing to spikes and valleys, et cetera. But I think without adequate education, it's very easy for a consumer to perhaps adopt less-than-savory dietary habits because their sole focus is on flattening that curve.

• 1:12:25Tim Spector?

  We agree on that. So, you know, for anyone who hasn't tried it, they are an amazing educational tool about how your body works. Okay? So it's like you suddenly do this amazing science experiment on yourself. And seeing how your body's reacting in real time, which is kind of, you know, it's amazing really. Ten years ago, you wouldn't have dreamt this would be possible. And we think that within five years, you know, most of the smartwatches might actually have some capability to do this as well. So it's not going away. Like any new technology, it's going to be misused by some people, or overused, or

• 1:13:06Tim Spector?

  overhyped, etc. And yeah, certainly for the type 1 diabetics, there was a time when they ran out of supply, so they couldn't get it. Absolutely understand why they were angry. People just doing it for fun when, you know, they're risking Right. You know, fatal hypos without them. So they're incredibly useful, but the, they are, a complaint against Zoe was that they weren't very reliable. We did a study where we gave 300 users, one on each arm, and looked at those, and they worked out really

• 1:13:46Tim Spector?

  pretty well, for the purposes we're using it. We've also looked at whether, you know, compared to standard blood tests, they are, do they add anything to just taking a baseline blood sugar, an insulin level, and a HbA1c? And by looking at over your two weeks, your time in range, and the very glycemic variability, you can predict who's unwell or not better than those baseline tests. So there is, we've shown there's a clear advantage, even in normal people, to having them as a predictive tool. There are lots of ways of misusing

• 1:14:29Tim Spector?

  them. I agree that if you don't have a clear program with it, that puts it into some context, you would You know, using it just as a toy, you reach some wrong conclusions. And one of the common ones is that the only way to eat is to have a completely flat.

• 1:14:47Rich Roll?

  Right. You eat a hundred percent fat diet, like you're gonna have an awesome curve, right? It's gonna be flat.

• 1:14:53Tim Spector?

  Exactly. You just put ice cream on everything, whatever it is, and you know, you just cream on everything, you sort it out. And clearly, that's wrong. And it, and that's why, something with Zoe, we see it's just one of the, of these three tests, really. It's, it's, it's one part of the, your score is your glycemic score. But we need to know how you handle fats. And that's why the Zoe test has a blood prick spot and your six hour triglyceride test, see how much is hanging around. And of course, your gut microbes and those, you know, we need a more holistic view of it, rather than getting obsessed about that one increment of it. Because you have, if you are going

• 1:15:36Tim Spector?

  to control your blood spikes for sugar, you've got to make sure that you're not giving yourself too much fats, you're tipping that. So your, your fats are hanging around the blood, you're gonna get atherosclerosis and inflammation. And also, the foods you're eating are also good for your gut microbes. So if you have a more holistic view of it, then I think it, it, it is reasonable to use these. And I think they are a great educational tool to show people that some of the common things they were eating, like their standard sliced loaf bread, which they thought was super healthy, is giving them this massive spike, which, you know, what mine looks like if I ate supermarket bread. And certain fruits, for

• 1:16:19Tim Spector?

  example, that they thought were super healthy and, like me, bananas, you know, which I used to take as my standard every single day fruit. Not particularly good for me. I think these are things are useful because they start making you think about food in a different way. And I think, but out of context, I think they can be dangerous to some people. But if you think about it, you also could think about your fats, you've got to think about how good that food is for your gut microbes. And accept that you will all, yeah, you can still have some sugar spikes every now and again. It's normal. That's physiology. Let's not get obsessed about it. But seeing it in real time is, is kind of cool.

• 1:17:00Tim Spector?

  And that's a glimpse, I think, of the future. You know, they'll soon, someone will invent a lipid test in real time and it'd be on your watch soon. So you'll be able to see how these

• 1:17:10Rich Roll?

  Right. All of these different readings about what's happening in real time within your body.

• 1:17:14Tim Spector?

  I think it's inevitable.

• 1:17:15Rich Roll?

  Which is interesting and fascinating. But like a real basic question here is like, why should we care about this? Like, we see, you know, let's say you have a CGM, you see the, you know, the, your blood glucose go up, it goes down. Why is this important? What is metabolic health? And why should we, you know, be paying attention to this in the first place?

• 1:17:38Tim Spector?

  These spikes in sugar and or triglycerides are part of normal physiology. So, you know, our bodies designed to do that way. But if there's too many of them, and the spikes are too prolonged, you either get a buildup of, so the sugar spikes will create rise in insulin, which can can start getting insulin resistance. And long term, you might end up more likely to get diabetes, pushing you towards prediabetes, etc. And that buildup in triglycerides are particularly related to inflammation. You get inflammation in the blood vessels, over time,

• 1:18:18Tim Spector?

  that stress builds up. And again, heart disease and other metabolic problems. So it's, the idea is that if you can calm that down, so you're not having as many of those spikes in the day, then your inflammation levels are lower. And we've shown that they are related to blood inflammation markers. You will reduce your risk of many common chronic diseases, most of which are related to some extent to what we call chronic inflammation, this sort of low level stress in the body. And

• 1:18:52Tim Spector?

  Other studies have shown that people who have are prone to these sugar spikes end up long term with more diabetes and heart disease. So there are there are sort of links you can make epidemiologically. We also know that some of these big spikes we showed, there's something called a sugar dip. So one in one in three men, one in three women, one in four men after a car be say breakfast or or lunch, three hours later will have a dip below baseline. And you say, well, okay, that's not to worry about. But we we followed a large number of these people and it turns out they report being more tired.

• 1:19:36Tim Spector?

  They don't know what their result, they were blind to their result, they were more tired, they were more hungry, and they overate by about 300 calories that day. So the sugar dips, which you get from highly refined foods and carbs, are actually making you overeat as well. So they, over time, will make you gain much more weight than someone who's not having these dips. So some people are even more susceptible than others.

• 1:20:03Rich Roll?

  And what is the relationship between metabolic health and the microbiome? Like, how does a robust, healthy microbiome, in turn, help you maintain a healthy, you know, a healthy metabolic, you know, sort of profile?

• 1:20:23Tim Spector?

  We don't know, is the is the true answer. But we do know that all this epidemiology studies show that people with poor metabolic health, so with type 2 diabetes, with obesity, with high blood pressure, with autoimmune disease, inflammation, all have low diversity microbes, poor ratios of good to bad bugs. So there's a clear association there. And then you can do studies in mice to show a cause effect relationship of these sort of inflammatory microbes that are maybe producing chemicals that are making the whole problem worse. So it's a bit of a vicious circle.

• 1:21:05Tim Spector?

  So the microbiome reacts to people with poor metabolic health end up getting unhealthier microbes. But we also know that having unhealthy microbes makes you more likely to also have poor metabolic health. So it's It's, it's, you know, it's both cause and effect relationships. So we don't understand exactly how they do all this. There's so many chemicals involved, so many microbes involved that we don't yet know the details, but we do know that there's these very clear associations and that you can improve metabolic health so dramatically in a lot of animal models by improving the microbes or things

• 1:21:49Tim Spector?

  like fecal transplants in mice and things like this. So.

• 1:21:52Rich Roll?

  Right. So in other words, if you, if you are getting an issue that, that you're having some level of insulin resistance, the immediate kind of first thing to do would be to make sure that you're getting 30 varieties of plants in your diet, like improving the quality of your microbiome, which in turn may have some positive impact on buttressing against that insulin sensitivity.

• 1:22:19Tim Spector?

  Yes.

• 1:22:20Rich Roll?

  Is that, is that a leap or is that?

• 1:22:21Tim Spector?

  No, I think, but that's, that's general for most of the chronic diseases that are related to inflammation. So yes, we know that people who have poor metabolic health have pro-inflammatory microbes. They have species that actually thrive off, you know, the stressed cytokines and, and all these other stress hormones. And if you can, if you can change those and get some of the good guys in there instead and drive down the bad ones, you can reduce some of the, the impact of those diseases. So these haven't been studied in big enough nutritional trials yet, but everything points that that is, that is the direction we should go in. And it, so far for most of these diseases, there

• 1:23:06Tim Spector?

  don't seem to be very specific microbes that are involved. It's more the general community is, is all changed. So it's just, the environment has just shifted. And it could be something subtle just by changing the pH of the gut, just a fraction makes a big difference between it being beneficial or pro-inflammatory and itself producing more of the problems.

• 1:23:31Rich Roll?

  That's fascinating. And, you know, as this continues to scale up, obviously you'll continue to learn more, right?

• 1:23:38Tim Spector?

  Yeah. And, you know.

• 1:23:41Tim Spector?

  Christopher Gardner, I know you're probably going to be talking to him soon, did a really neat study where gave intensive amounts of fermented foods to volunteers and looked at their inflammation and immune levels over the next few weeks. And they showed, one arm was given just fibre and the other arm was given fermented foods. And both groups improved to some extent, but the one that had the biggest immune impact and reduced inflammation was the fermented foods group. So we know we can change in just a few weeks. Quite a lot of these, these basic mechanisms that are important to so many chronic diseases.

• 1:24:22Tim Spector?

  And yet, most doctors never suggest these as treatments. They always, you know, reach for the prescription pad. It's amazing how fast that is too. Yeah. How mutable it really is. That was the surprising thing, that it just, it was, it was four weeks of intensive meal deliveries. So they knew, you know, they were, they were getting this, this stuff. And then they had four weeks where they were just trying it on their own. But it was, you know, the results really were very striking and that's what, it had a really big impact. But no one had done those studies before, which is shocking as well. Right, right, right. Because we just said, oh, well, that's just yoghurt, that's not real treatment, you know, that's, that's hippie stuff. You know, we don't, we don't believe in that.

• 1:25:07Tim Spector?

  But these, you know, luckily they did all, you know, a huge range of, of blood tests and, and microbe tests. So, yeah, in a few weeks, you can really change your, your gut health and influence disease. And I think that's, that's the message. And this whole message about why, you know, medicine might, why food really is medicine. And we should come back to that, you know, not start saying, well, you have to be a nutter if you're. Yeah.

• 1:25:33Rich Roll?

  Did Hippocrates actually say that? Or is that apocryphal?

• 1:25:39Rich Roll?

  We don't know.

• 1:25:40Tim Spector?

  I haven't seen his original text. But it's nice to think he would have said it.

• 1:25:46Rich Roll?

  I like to believe that as well. The other kind of really exciting, interesting field where we're seeing a lot of exciting developments is at the intersection of the microbiome and cancer research, right? So explain a little bit about what's going on with that, specifically with respect to melanoma and to some extent even lymphoma, right?

• 1:26:13Tim Spector?

  Yeah, well, it all comes down to this new approach to cancer, which is to realize that it's actually an immune problem rather than a sort of mutation problem. Because we're all getting micro cancers all the time. And our immune system, if it's healthy, is picking them off before they get too big. And so that's why the immune system, aging and cancer have got this sort of close link. We've never really realized how important it was until these immunotherapy drugs come along, these so-called checkpoint inhibitors, which have been sort of game changers for many people with some of these solid tumors, particularly melanoma, but to a lesser extent

• 1:26:58Tim Spector?

  kidney and lung and some prostate. That you're using these drugs to boost the immune system, to attack the cancer cell and get around its defenses. And so, you know, mortality rates were sort of, you know, 95% and these drugs have really changed it. So they've halved, doubled the survival rate in these particular conditions. It doesn't affect most cancers, but these ones. And what we've seen is that the...

• 1:27:41Tim Spector?

  There were some early studies showing that the microbiome might have a role in this. And that the state of the microbiome was important. Because it was interacting, because as I mentioned, how important it is for the immune system. And you want a really powerful immune response in order to fight that cancer for that drug to work. So a few early studies of this suggesting this might be the case. And we got together with a UK charity and got a consortium of other cancer centers in the UK and the Netherlands. And we got several hundred melanoma cases, end stage. These are people with terminal metastatic cancer going through their immunotherapy.

• 1:28:25Tim Spector?

  And saw how they did over a year. And it turned out that the state of their gut microbiome at the beginning was one of the biggest predictors of whether they would survive or not. And as expected, it was, you know, the good to bad ratio, loss of diversity. And we also looked at their diets and it was the lack of fibre. And positive aspects of those that followed more Mediterranean diet had like double the rate of success of survival. And, you know, these figures aren't trivial, it's not a tiny amount.

• 1:29:05Tim Spector?

  If, you know, real difference between double your chances of success of reaching 12 months. Wow. And yet, how many patients know, you know, the importance of this? Yeah, yeah, yeah, it's interesting. How many oncologists discuss diet in such a powerful way? And there's, you know, there's been some studies in for chemotherapy. It haven't been very clear or very large, which is, you know, this way you just sort of try and kill all the cells. And there is some hospitals, like I think it's Sloan Kettering.

• 1:29:48Tim Spector?

  Or M D Anderson, where they actually, if you're going through chemotherapy, they will take a sample of your gut microbiome and they'll store it in freezers. You have your chemotherapy, then they give it back to you as a booster. And so, and they've got data that improves survival as well. So you-

• 1:30:06Rich Roll?

  I mean, that makes perfect sense. It's common, I mean, you're saying, it's immediately what I thought of, like, no matter how robust and great your microbiome is, if you're going into chemo or radiation, it's going to get obliterated, right? So to culture it and be able to, you know, supplement or kind of, you know, a lot, you know, have, have a way of repairing that as you go along would seem to be kind of crucial and obvious.

• 1:30:31Tim Spector?

  And I think we're all going to be storing our microbiome when we think we're at our healthiest. It's always hard to know.

• 1:30:37Rich Roll?

  Yeah. Well, trust me, I'm going to get into fecal transplants. Like, we, yeah, we should all, we should have banks where we're, where we're storing this stuff at our healthiest, right? So, you know, when we face some kind of crisis, we have the ability to kind of turbocharge our, our, our microbiome and in turn, our immune system so that we can meet whatever we're facing in the best way.

• 1:31:00Tim Spector?

  And as you said, there's some other examples in lymphoma, something called CART therapy is very complicated, using T cells. And the microbiome, again, is, is proving crucial in those, lymphoma, just like a type of leukemia. So I think we're going to see more and more of this. And I'm, I think the cancer area is one that the public can really relate to. And this might be finally the barrier that gets it across to the medical profession, how important diet is, and diet and gut health, because medics are still not being taught anything about this, this whole area. And nutrition is still sidelined as

• 1:31:42Tim Spector?

  a minor thing. But if we can show how important it is in cancer, then hopefully, everyone will be convinced and the word will get out.

• 1:31:49Rich Roll?

  But cancer patients are traditionally told to avoid fermented foods.

• 1:31:55Rich Roll?

  Right?

• 1:31:56Tim Spector?

  They are, yeah, they certainly are in many places and I get lots of complaints from patients saying.

• 1:32:01Rich Roll?

  Because, what is the rationale?

• 1:32:04Tim Spector?

  I think it comes to the days when, at some point in chemotherapy, you are very vulnerable to infections and so you have very few white cells to fight infection and so they're worried about introducing bugs and obviously at that nadir in your treatment, you don't want to be given large amounts of microbes, but for the vast majority of people, most of the time, these fermented foods could actually be saving their lives. So there's a lot of misinformation out there and that we need to, you know, get oncologists and doctors up to speed on this new area. It's moving very fast. But fermented foods are

• 1:32:48Tim Spector?

  really good for your immune system and as far as I know, that, you know, they've never killed anybody who isn't, who's got a few, you know, decent, some white cells.

• 1:32:58Rich Roll?

  Yeah. So, so paint the picture of what the future in your mind looks like from a personalized medicine perspective and a diagnostic and treatment perspective when you're able to perform, you know, really dialed in specific citizen science and, you know, data crunching to, you know, create, to create really powerful tools to treat better in a more bespoke way. I mean, what does that look like? Like I'm imagining...

• 1:33:31Tim Spector?

  How far, how far in the future are we talking?

• 1:33:33Rich Roll?

  Well, maybe like, you know, 10 years from now and 50 years from now. Like I've had futurists on here. I've heard, you know, like, I think what's happening in terms of...

• 1:33:41Tim Spector?

  I can't go beyond 10 years, I'm sorry.

• 1:33:43Rich Roll?

  Well, like, you know, there's a lot of interesting breakthroughs and developments in scanning and early detection and all of these things that are, I think are really powerful in terms of catching things early on. Like so much of what we perish from is avoidable if we could have caught it earlier. And, you know, kind of the technology is getting to a point where we're going to be able to detect these things so early on that we can, you know, deal with them in a really facile manner, you know, before they become problematic. But...

• 1:34:13Tim Spector?

  That's early treatment.

• 1:34:14Rich Roll?

  Yeah, that's, yeah, early treatment, right? And, and what you're talking about is just another piece in that, in that broader puzzle in terms of like where... Medicine and healthcare are heading, but you know, what is your, what does it look like from what you're seeing?

• 1:34:30Tim Spector?

  Well, I'd love to see more about prevention rather than sort of early treatment and reverse the major threat to the Western world, which is our poor diet, which is essentially killing us and giving half the population, the US, you know, make diabetes and obesity.

• 1:34:51Rich Roll?

  It's an insane statistic when you think about it.

• 1:34:54Tim Spector?

  And so, you know, ultra-processed food is the number one killer in this and the studies are clearly linking ultra-processed foods and microbiome dysfunction and we've just let it happen. You know, we just let all these chemicals come into our food system without a proper testing and the science is now showing that many of these emulsifiers that glue stuffed food together, the artificial sweeteners, the sugar alcohols, all these things that you see in ultra-processed foods have a negative effect on our microbiome. So, you know, I'd like to see a future where we're not just fighting an ever-increasing

• 1:35:37Tim Spector?

  number of diseases with expensive MRI scans. We're actually going to do something at a population epidemiology level to say, you know, these foods, they're like, it comes to cigarettes in the 1970s, you know, they should have health warnings on them, not health promotion benefits to say, this is healthy because it's got some vitamin D.

• 1:35:59Rich Roll?

  Iron or whatever it is.

• 1:36:00Tim Spector?

  Yeah.

• 1:36:00Rich Roll?

  Yeah, fortified with vitamin C or D or K.

• 1:36:04Tim Spector?

  There should be a warning says, if it comes, if it comes with some health advice, it's bad for you. You know, that would be a good sticker.

• 1:36:15Tim Spector?

  So I'm really into prevention and I think we're gonna see that the tools for, you know, rather than trusting in doctors, that individuals are empowered to do this themselves. I think this is the way it's gonna happen. And we've seen already, you know, how these devices are changing people's lives just in the last few years. The glucose monitor, there'll be the lipid monitor. We know all the major smartwatch manufacturers are gonna be moving towards this. They'll have laser devices that will be able to pick up different blood measures in you in real time. These will be fed back through algorithms in your phone.

• 1:36:54Tim Spector?

  And, you know, the vision of companies like Zoe is to also tell people not only what's happening to their body in real time, but what they're eating in real time. So with the complexity of the ultra-processed food, it's very hard to know what you're actually eating. How bad is it? How many of these chemicals are bad? Are you the one in three people that reacts to carrageenan, you know, which is an emulsifier that will glue your microbes together but not other people's? You know, which artificial sweener, if you have to have one, you know, would you have? This level of personalization can only be so complicated, you need apps and advice to be able to do it, to guide you through it.

• 1:37:36Tim Spector?

  So I think we'll be using these devices to find our way through the food jungle, point us to say what ideally we should be eating, keep us logged about how well are we doing in our 30 plants a week, hints of new things to try, and telling us when we should be taking our exercise relative to where our last night's sleep was. Everything should be optimized, but also not just making us robots, but making us more intelligent, more educated about what we're doing. So that we realize, you know, this is an evolving science and if everyone is part of

• 1:38:18Tim Spector?

  a giant citizen science project, then everyone benefits. And I think that's my vision of the future, is that we will have this sort of benevolent...

• 1:38:30Tim Spector?

  Companies like, there'll be a group of people who can pay for all these tools, but that information will pass to the people that can't pay for them. And they will get predicted scores that are free and we'll move to a time when this is possible. So realizing that, you know, as we talk about cancer, yes, you can have an MRI scan that can detect that cancer early, but wouldn't you be better to know how to boost your immune system so that your immune cells do it, beat that cancer before it's even detected by the MRI scanner?

• 1:39:03Rich Roll?

  And rather than rely upon the food pyramid, that's the result of a political process, to have a personalized food pyramid that is specific to you and you alone, which is what you talk about in the new book.

• 1:39:19Tim Spector?

  I think this is definitely the future, but it's also understanding what the foods we're eating and, you know, and moving away from this old fashioned idea of calories.

• 1:39:30Rich Roll?

  Well, let's talk about that, like it's a good segue into the new book, but let's bust a few diet myths, right? Like macros, calorie counting, like come at me. Like I know you got a lot to say about this kind of thing.

• 1:39:45Tim Spector?

  They exist, but you know, their importance has been massively hyped. And the idea you can describe food by calories and by macronutrients has been exploited to the nth degree by the food companies. And that's why they can sell us all these products with these health claims on them, when we know they're rotten, they're artificial, you know, they're just, they're fake food. But because they have the right macronutrients on the label, they get a nice tick and we're poisoning ourselves. So I think. You know, we haven't really changed in a hundred years our basic concept of how to

• 1:40:30Tim Spector?

  discuss nutrition properly. And we're only just starting to get into this discussion of what ultra-processed food is and the different levels of food processing, which the food industry doesn't want us to discuss because the last thing they want is some definition that they would have to apply to. So they are keeping muddying the water on it. So the fact that they, you know, the companies, and I discuss this in the book, you know, love the idea of calories, they love calorie things on menus, and they're describing food by its, as if you can tell if it's food good or bad by its calorie count and its fat content. It's complete nonsense.

• 1:41:13Tim Spector?

  There is no real correlation, and there are good and bad fats, and there is good and bad calories, foods. You know, we need to be focusing on the quality of food, and that's totally clear. Like the example I gave you in the Zoe study of people given an identical calorie muffin, and some people react to that in a very different way and get a sugar dip and will overeat by 300 calories later in the day, others won't. If you describe food purely in terms of that, all calories are equal, and you just gave everyone these bad, bad foods, you wouldn't know that this is what this effect they're

• 1:41:57Tim Spector?

  having on mood and energy and everything else. So smokescreen that we just need to get rid of, and we need to start talking about quality of foods, and what's whole food, you know, what's a whole plant food, not these foods that are made in a way to falsify real food. You know, they're designed to reformulate actual food using fake ingredients, extracts. And I think that's...

• 1:42:28Tim Spector?

  You know, no one denies that calories exist, but you know, we can go into the whole thing about why calorie counting diets fail the vast majority of people. It will work for a few weeks, then your body just readjusts and bounces back. The same way, exercise for most people does the same, because your body adapts to that exercise. You know, we're not just furnaces, we're finely tuned machines that change. So, these are concepts that have just stayed because of the market, the force of the calorie counting diet market, the force of the food industry trying to sell us worse and worse

• 1:43:12Tim Spector?

  food with more and more health claims. And I think the science is now out there to show how irrelevant they are and how they are just a smokescreen.

• 1:43:24Rich Roll?

  Yeah, there's sort of an arms race also, because as the public becomes increasingly more and more aware of the ills of ultra-processed foods, at the same time, the giant conglomerate food companies are getting better and better and better at dialing in palatability and the addictive nature of these foods with the exact recipe or combination of salt, sugar, and fat to kind of light up the dopamine centers and make it impossible to just have one. So it creates this sort of compulsive relationship with foods we know are not good for us, and

• 1:44:07Rich Roll?

  yet we find ourselves powerless to deny, right? So, education takes us to a certain place, and you know, human frailty and weakness accounts for the rest. So, you know, it's sticky to like...

• 1:44:22Tim Spector?

  Well, I've got no... I don't really have a beef with foods that are obviously unhealthy but super tasty, right?

• 1:44:32Tim Spector?

  When something is wrapped up in all this healthy packaging and is sold to you as a healthy, low-calorie, low-fat alternative, that's criminal. It's like dressing up cigarettes as healthy because they're low in, like, it used to be low tar or low nicotine, therefore, they're fine.

• 1:44:58Rich Roll?

  Right, yeah, that's like the sort of the tobacco company version of greenwashing. It makes us just feel a little bit better about that purchase, you know, making that purchase.

• 1:45:08Tim Spector?

  Exactly. So, you know, let's have, we're not going to get rid of them, but let's have them with health warnings, let's have them with a tax that reflects the huge burden on the taxpayer that all these foods are costing us, you know. So it's hundreds of billions of dollars a year just because of we're eating these foods. And why should the taxpayer be basically paying for all this when the food companies are making all the money? And, you know, and they're getting massive subsidies to do it. And whereas anyone producing whole plants and fruits is not getting those same subsidies.

• 1:45:47Rich Roll?

  Right. Right. I mean, I agree with you completely, but then it becomes a question of political will and kind of penetrating the, you know, the battalion of lobbyists who are, you know, very invested in the status quo.

• 1:46:00Tim Spector?

  Yeah.

• 1:46:01Rich Roll?

  While we're all getting diabetes and becoming obese and dying of chronic lifestyle illnesses.

• 1:46:06Tim Spector?

  There will be a point when the country just won't be able to afford it.

• 1:46:08Rich Roll?

  You know, the healthcare system is broken. So it's, it is, and it's a national, it becomes a national security issue, honestly. Like, it's a really huge problem, and yet it continues to persist and metastasize, which is disturbing. But perhaps we can, you know, pivot to a more optimistic or helpful conversation around, like, how to guide people towards those better choices. I mean, we all know more fruit, more fruits and vegetables, nuts, seeds, you know, that's the kind of thumbnail. But for the conscious consumer who's just going to the supermarket and shopping for their family and is on some level of budget, what are some of the kind of guiding principles

• 1:46:51Rich Roll?

  about what to avoid and, you know, what to invest in?

• 1:46:55Tim Spector?

  Well, there's a lot to avoid, but in writing the book, there were some surprising findings that I found that things that are relatively cheap aren't always unhealthy. So, things in cans. Many studies have shown that some canned tomatoes can have higher nutrient levels than fresh tomatoes, for example. You get a can of beans, they're just as healthy as getting, you know, dried beans and doing them yourself, and they're often extremely cheap, really good source of protein.

• 1:47:34Tim Spector?

  Most frozen vegetables and berries are also highly nutritious and really good for you and cost virtually nothing. So, we tend to think of anything frozen or in cans or in packaging as all the same. It's absolutely not true. As long as the sauce, it doesn't have, you know, an artificial sauce in it, it's going to be really good for you. So, that was a surprising finding that many of these products you can get out of season, frozen berries, for example, out of the freezer, really good for you. Nuts, you know, there's nothing wrong with nuts as a snack.

• 1:48:12Tim Spector?

  And there's a big difference between some artificially created snacks, like, you know, things like Pringles, which have very little potato in them, they're actually made of all kinds of a composite of other things, versus some artisan potato chips that you can get that only have potato and olive oil or sunflower oil. So, there are some surprising ones in there, but unfortunately, the vast majority of ready meals that you buy have large lists of ingredients in them that you can't, wouldn't find in your home, and they're the ones that will cause you problems, they will make you overeat,

• 1:48:56Tim Spector?

  and they will be bad for your gut microbes. And I think that's a really important educational message that needs to get out there, is that it's not about the fat, it's not about the calories, it's the fact they have this really harmful effect on your immune system, and...

• 1:49:12Tim Spector?

  You're gonna eat more and more of them, so they might be cheaper, but you're gonna they're made for a purpose so that you'll be overeating your family and you will put on weight and have all these other diseases. So I think it's this education about what's wrong with certain foods that are, you know, ultra-refined, have to have fiber, very little nutrients, get into your bloodstream quickly, don't fill you up. And they're just plain wrong. We weren't designed by evolution to eat them.

• 1:49:42Rich Roll?

  Right.

• 1:49:43Tim Spector?

  And that, so to my mind, it's it's it's an educational way of thinking, but realizing there are some, you know, things that look quite similar that actually are still very good for people, but they're they're not eating.

• 1:49:55Rich Roll?

  Yeah. Your dietary perspective and recommendations, although very plant-focused and kind of plant-centric, are not ideologically sort of driven and and they're not super strict in that regard. They're more like, this is what looks like the science supports, and this is what I'm, you know, advising you to do and not do. And an added wrinkle on top of that, that I found really interesting in the book, is addressing not only how the food is prepared, like, have you cooked it? Is it better to eat raw? Or this is stuff I've thought about often, like, should I eat this vegetable raw, or is it better cooked?

• 1:50:37Rich Roll?

  Is it better to light? What happens if you overcook it? Am I destroying all the nutrients in it? And then also, how is the food packaged? What is the impact of, you know, food that's wrapped in plastic? And particularly, if you end up like heating that food up while it's in the plastic. And you kind of address all of these, which I think are, you know, kind of common questions we all think about, but maybe don't pay enough attention about. So can you kind of unravel some of that?

• 1:51:04Tim Spector?

  Well, it's a lot to unravel.

• 1:51:06Rich Roll?

  Yeah, I mean, there's, it is. I mean, you can read the book, but like, maybe some sort of general principles around that.

• 1:51:12Tim Spector?

  Yeah, well, I think a little bit comes down to understanding a bit more about the structure of food and Cooking changes the structure of food, so yeah, there was a common misconception that raw food is better for you, and the raw food movement has led to a lot of this. But all the science suggests that actually lightly cooking food is the optimal. So lightly steaming your food breaks down the structures, allows the nutrients to come out without destroying some of these vitamins and nutrients. And these polyphenols, we talk about these defense chemicals that are in all plants that are really rocket fuel for our gut microbes, that are really what we should all be trying

• 1:51:55Tim Spector?

  to get more of, that definitely aren't in ultra-processed foods. So, understanding the structure of food and how you're cooking is really important. Understanding that, you know, freezing stuff, even microwaving is fine. Before I researched the book, I was, oh, I'd got rid of my microwave, I thought this is terrible, you know, it's sort of... But it turns out that actually, it doesn't destroy nutrients in any way, it's actually good, and it's much better for the planet. So in terms of the energy used, you know, if you say a baked potato in a microwave, it's much more efficient for climate change to use it.

• 1:52:34Rich Roll?

  From an energy expenditure perspective.

• 1:52:36Tim Spector?

  Energy expenditure perspective. It may not taste as good.

• 1:52:38Rich Roll?

  I still struggle with the idea of like having a microwave, but go ahead.

• 1:52:41Tim Spector?

  But, well, I was like you, you know, I thought, but in a way, having researched the book, I've said, well, if I care about the planet, I should use both of these tools, you know, and not be so obsessed with my prior beliefs. So structure of food's important, how you cook it's important, what you cook it with. So just combining foods together will change their nutrient value as well. So a lot of these Mediterranean dishes, we'd use olive oil and garlic and onions, you know, collectively, they actually produce many more healthy chemicals together than they do when you have them alone.

• 1:53:21Tim Spector?

  Chopping up your garlic 10 minutes before you use it actually trebles the amount of these really beneficial nutrients in the garlic that otherwise would get broken down. So all these kind of funny weird stuff about structure of food is useful for people to know in everyday life about how to cook things.

• 1:53:49Tim Spector?

  Yeah, obviously, cooking stuff close to plastics, and you've alluded to some of this, you know, the problem of microplastics is something we should be aware of. We don't really know enough about it, except there's lots, far too much plastic around, and so limiting the plastic that's close to our food is also important. And I think the other thing I realized is that no one had really written a book before that looks at all the different food groups and first takes health, then takes the ethics.

• 1:54:26Tim Spector?

  So, you know, were animals, you know, engineered, what's the ethical basis of that, or what's a lot of, there's a lot of new stuff about child slave labor, for example, chocolate and that, and coffee and various other tropical things that we need to be aware of. But also, finally, the big other area is the environment. Sure. And it was a bit of an eye-opener because it's quite hard often to balance these three things when you're making, you're going into a store and you want to buy something nice and you're trying to work out all of, you know, to get all three perfectly aligned

• 1:55:05Tim Spector?

  at the same time is kind of tough. And so, particularly when it comes to something like artificial milks. So I found that really interesting because I'd experimented with cutting out dairy milk, and the main reason for me to cut out dairy is because of its harmful effect on the planet when you calculate how many cows and methane and land, land use, etc. So it makes obvious sense to cut that out. So I switched to oat milk, which, you know, I didn't mind the taste of it, it seemed quite good. But then I put a CGM on me while I was drinking oat milk and I saw it shoot up. So suddenly I've swapped

• 1:55:47Tim Spector?

  what was this reasonably healthy fat, mild sugar mixture for a much higher sugar, much more refined product, meant that if I was having regular oat milk, it would, for me, it'd be bad. Other people might be fine, but it would, that would be better for the planet if we all switched to oat milk. But it would probably cause more, have some disease consequences as well. So there are lots of examples of how Tough it is to balance some of these things. And, you know, are you going to get them from Mexico every week? Are you gonna... How do you freeze them enough? And where do you get the nuts from? So it starts to ask a lot of questions. Not...

• 1:56:32Tim Spector?

  We don't have all the answers, but I think it made me think, and I want people to read the book, to think about food in a very different way. Because the food choices we make every day are the most important choices we make for our health and probably also for the planet.

• 1:56:49Rich Roll?

  Yeah, 100%. I mean, every purchase of food that you make is a vote for the world, you know, that, you know, will be, right? So it would be great if there was some kind of metric or carbon score or some numerical value that we could attribute to each food, you know, sort of product, food product that we buy, that would kind of tally, like, what is the carbon footprint of this? You know, what went into the manufacturing and distribution of this? You know, what was the amount of, like, water and acreage? And, you know, all of that. And, you know, were animals killed in this?

• 1:57:31Rich Roll?

  Or, like, you know, so it's impossible to put all that on the consumer and expect them to, like, really be able to make an informed decision, especially when the larger food companies are doing their best to obscure any kind of transparency around that.

• 1:57:47Tim Spector?

  Well, there are academics who have produced scores, and we're working with them at Zoe, and we do have a sort of beta score for all the common foods that gives you an environmental index. And obviously, the Zoe program is designed so that you, you know, you get your general Zoe score. And I've got my scores in the book for various things, which is a combination of the three. But so we're thinking sometime in the near future of adding in that fourth score, which would be the environmental impact score, so that people who wanted to... Prioritize environment above health. Or habit is a major factor could actually have that. But it is so complicated, it would be, it does need algorithms and an app.

• 1:58:32Tim Spector?

  You can't retain all of this stuff in your head, knowing if that avocado comes from Mexico or it came from California, you know, what's the difference or, you know.

• 1:58:41Rich Roll?

  And also labeling is not reliable. It could, you know, all the, all the, the obscure language around labeling, you think you're buying something that was grown in a certain way. And, you know, most likely wasn't. And that opens up a conversation around, you know, a different, you know, a different component of, of the microbiome, which is the sensitivity of our, of our, you know, larger microbiome, not just to the foods that we're eating, but environmental toxins, the air that we breathe, the personal care products that we use, skin creams, shampoos, et cetera. And not for nothing, the pesticides that find their way onto the foods that, that we're

• 1:59:24Rich Roll?

  eating, that we're not even aware we're consuming, whether we're washing them or not. And there's a spectrum of, of harm associated with that. But, you know, how do you think about that? And have there been studies done to give us a real grounded scientific sense of the harm or lack of harm? Like, what is the level of concern that we should have around that?

• 1:59:52Tim Spector?

  Well, in researching the book, I mean, obviously looked at things like glyphosate and herbicides in particular. Because I was wanting to look at exposures that nearly everyone has had. And the problem with this kind of study is pretty hard to find people who haven't been exposed. Because whether you live in a rural area and there's lots of spraying around you or you eat a lot of vegetables. Or you eat breakfast cereal.

• 2:00:18Rich Roll?

  We all have glyphosate coursing through our veins.

• 2:00:20Tim Spector?

  All of us have glyphosate. And, yes, the studies have shown that if you have organic food, it has a fifth of the glyphosate levels of non-organic food. But you're still getting some. So everyone's exposed to some love.

• 2:00:34Rich Roll?

  Because it's just blowing around in the wind from the neighboring farm and finds its way into the soil of the organic farm.

• 2:00:41Tim Spector?

  And obviously, as I start to eat more plants, I get a bit more nervous about this because you don't get glyphosate on beef, for example, or, you know, or meat.

• 2:00:49Rich Roll?

  You get a whole bunch of other stuff.

• 2:00:50Tim Spector?

  But, you know, so it's, but you're obviously compensated by, you're eating lots of plants and vegetables. I think you're doing the right thing. But if it's not organic, you are actually ingesting more glyphosate. And I certainly raise, there are also certain types of plant where you get many more. So if you like oats, and I know Americans love their oatmeal in the morning, think it's a healthy food. It has really high levels of glyphosate when the people have tested breakfast cereals because oats and rye, to dry them out, they'd spray it out as a way of harvesting it quicker. So used for different purposes. So I have a real problem with something that we're ingesting every single day of our lives, what effect that has on our bodies.

• 2:01:34Tim Spector?

  Now, the science isn't, the epidemiology isn't conclusive. There's a suggestion it increases lymphomas. And there are some, there've been some court cases on that. They've done some mouse studies that show that it does affect the gut microbiome. Because these chemicals were designed so they didn't affect human genes. So they don't, not supposed to interact with human genes. But they're supposed to kill plant genes. And they, and as collateral damage, they take out quite a few of our microbial genes as well. So we are seeing disruption in the gut microbiome due to glyphosate.

• 2:02:19Tim Spector?

  And they...

• 2:02:22Tim Spector?

  Animal models have shown that they do produce abnormal chemicals. Now, that's really all we know at the moment. There's nothing definitive, but it's sufficient to worry about. And there have been epidemiology studies, such as one in France, where they compared a group of people having organic foods regularly versus non-organic foods and found big differences in cancer and mortality levels over the next 10 years. So, there's enough for me to worry about. I'm also worried about microplastics. I think we don't understand that, and we do know that they do get into our gut and can cause disruption in our gut microbes as well.

• 2:03:05Tim Spector?

  And there are also enough, if you eat a lot of fish, you know, because you think fish are healthy, and I go into that in the book.

• 2:03:12Rich Roll?

  Marky.

• 2:03:13Tim Spector?

  And if you go to a nice, non-sentient fish like mussels and say, "Okay, I can eat those," they're great, they're really healthy, nutritious, but they've got a lot of microplastic in them because they suck it out of the sea. So, we're sort of screwing up our planet slowly, so all these good things we're having a problem with. But, so, you know, I think there is pretty good evidence that these pesticides, et cetera, and are bad for newborn babies and pregnant women, and increase, they've done some small-scale studies.

• 2:03:54Tim Spector?

  Evidence for the whole population isn't yet definite, but certainly, if you can afford it, then definitely go organic, is my advice. And unfortunately, in most countries, it's still more expensive, and that's a problem.

• 2:04:11Rich Roll?

  Yeah.

• 2:04:12Tim Spector?

  But I do worry about, but having said that, it's still better to eat vegetables and not worry about the pesticides than not eat the vegetables and the fruits.

• 2:04:22Rich Roll?

  Yeah, and you can go to the Environmental Working Group's list of the Dirty Dozen. There's a spectrum of harm with respect to that, if you're budget-conscious about what's the most important food group to be organic versus conventional.

• 2:04:38Tim Spector?

  But yeah, but your breakfast cereal in the US is one of the biggest sources.

• 2:04:43Rich Roll?

  Well, you should just get rid of that, like just cross it off the list, right?

• 2:04:46Tim Spector?

  We can agree. Have a health warning like a cigarette packet and then say, yeah, if you have this at your own risk, you can't sue us if you get cancer.

• 2:04:55Rich Roll?

  What is your thoughts? A big piece of, let me preface this by saying, I think, I think, you know, the scientific consensus is pretty clear that if you want, that you want a healthy microbiome, that having a robust and healthy microbiome is so crucial to so many facets of health and we're only, and that, and that, the level of that relationship and importance is only growing as more science is coming out. And a key component to maintaining the robustness of that ecology is a diversity of plants in your diet. You talked about 30

• 2:05:33Rich Roll?

  plants a week, eating a diet that's high in fiber, that is high in prebiotics and fermented foods, which are probiotics, et cetera. And with that, what is your response to this growing enthusiasm around what's being called the carnivore diet, which is a diet that is, if not exclusively meat, is almost entirely meat-based? There's a lot of people, particularly on the internet, who are espousing the benefits of that, saying how much better they feel, how it helped them resolve whatever kind of chronic ailment they had. And this seems

• 2:06:16Rich Roll?

  to be more than a fad at the moment. Like, there's a lot of people who are very enthusiastically, you know, sharing their anecdotal experience with this.

• 2:06:30Tim Spector?

  Well, the good, the good side of it is generally these people are not having ultra-processed foods.

• 2:06:36Rich Roll?

  Agreed.

• 2:06:37Tim Spector?

  So they are doing some good in that.

• 2:06:41Tim Spector?

  Where, and I also get people saying, "I've been on a carnivore diet for two years, I feel great." You know, "What are you talking about? You need all these plants." We do know that people who don't eat plants, a variety of plants, have less diverse gut microbes, their microbial health is generally poor, which means they will have a poorer immune system. And so my worry about the carnivore diet is that it is, it may work short term, they might feel better, and so, not everybody, I know some people who really can't tolerate

• 2:07:21Tim Spector?

  those levels of meat or fats, and we know this is, there's individual variations, so there are some people who can tolerate it, and for a short while will feel better, might lose weight, might feel they're getting, you know, they're feeling stronger, etc. And that, I think that's genuine, but long term, they're going to be causing harm to their system, their immune system, because they're not nourishing those gut microbes. They're, you know, the average American has, you know, only half the microbial species of, say, that had a hunter, our ancestors, through antibiotics, through poor foods, through ultra-processed foods, etc., etc. So, they're going to be denuding that even more.

• 2:08:04Tim Spector?

  And so, that means their armoury of chemicals that they can use to fight infections, to help negotiate their energy balance, their metabolism, etc., is going to be used up. So, whenever they have a problem, they're going to, they're going to be in trouble, they just won't have the tools to be able to deal with it and have an immune system that I think is going to be wanting, for most people. I'm not saying there are some rare individuals who might be able to get by for longer than others without this problem, in general, it's a problem. And I think the other misconception is, this is what our ancestors ate.

• 2:08:41Tim Spector?

  I mean, I spent a week with the Hadza tribe about five or six years ago, and saw firsthand what these hunter gathers in Tanzania, what they actually eat, and...

• 2:08:56Tim Spector?

  You know, I exactly as they did and, you know, I was filled up at about 10 o'clock with baobab porridge, which is this, it just falls off the trees and you mash it up with a bit of water and that's your, that huge, high fibre mass, you can't stop farting after that, you know, you're just so full of fibre, you're eating berries, then at lunchtime you'd have, the women would dig up tubers, which are like, you know, ancient yams, like a sort of form of sweet potato and that would be lunch and then the guys would go out and do a bit of hunting and on top of that,

• 2:09:36Tim Spector?

  they would bring back some meat if they, if they found any. But for large periods of the year, they'd be having no meat and the, most of their calories would come from the carbohydrates. And if there's honey around, they, they didn't want meat, they just, they just went for the honey, they just, they stopped hunting completely, they, you know, just satiated themselves on the honey. So people have a very different perception of what our ancestors were actually doing and the majority of what their, their food was, was plant-based and carbohydrate-based. It wasn't a high protein, high fat diet. And they have the healthiest gut microbes, they don't get chronic diseases, they never get

• 2:10:21Tim Spector?

  cancer, all these things that we've now diverted as part of the West.

• 2:10:26Rich Roll?

  So the Hata is, for people that don't know, an African traditional hunter-gatherer tribe that has been able, for the most part, to maintain their lifestyle and their traditions amidst a rapidly kind of encroaching, developing world. And they have the most robust microbiomes because they have a very robust environment and extremely diverse amount of plant life on which they, you know, they, they sort of persist and exist, right? But it's, it's, it feels like there's a, there's a deadline on that. I don't know, when were you there? Like it, like it's, the world is encroaching on them, right? And some of their traditions

• 2:11:10Rich Roll?

  are beginning to erode and their dietary habits are, are starting to kind of shift as a result of that. Which is awful.

• 2:11:18Tim Spector?

  The area they're in is getting squashed by people cutting down trees around them and pastoralists moving in and of course, you know, they've got all these researchers around them now.

• 2:11:29Rich Roll?

  Right, everybody wants to study. I have a guy coming in tomorrow who went down and lived with them also.

• 2:11:34Tim Spector?

  Yes.

• 2:11:34Rich Roll?

  For different reasons, but yeah.

• 2:11:37Tim Spector?

  So, yeah, I mean, you know, hopefully they will survive a bit longer, but they're sort of running out of room. And they are the last true hunter gatherer tribe really in Africa. And, but I think it's really important we do learn the lessons from them. And we've learned so much about sleep and exercise and calorie burning and all these amazing things that have gone counterintuitive to what we believed. We thought, you know, in fact, they don't burn many more calories than we do and, you know, and they're not, you know, they're not running all the time either, you know.

• 2:12:22Rich Roll?

  And they're happier and they're more connected to their community and their neighbors and their family members. For the most part, anybody I know that's had any contact with them said, you know, basically they're, they're, they're doing it a lot better than we are.

• 2:12:36Tim Spector?

  Exactly. And you don't see obesity, you don't see diabetes, you know, and they die when they fall out of trees or they get hit by animals. So, you know, it's not, they don't live to ripe old age, but they don't really have a concept of age. And it was just interesting and, you know, it was fascinating to see them, you know, I asked them, when do you have breakfast? And they didn't have a word for breakfast. So, this is again, you know, an invention of perhaps calogs that we all have to have breakfast and otherwise, you know, we're, we're not eating healthily. And so, you know, it is this last chance to see how we did evolve.

• 2:13:17Tim Spector?

  And I think they've been there for, you know, at least 15,000 years or in that similar sort of environment, which is, you know, where we're supposed to evolve from, you know, around the equator. So, yeah, it's, it's a pity, but yeah, we've learned a lot from them. I certainly did. My microbes actually.

• 2:13:37Rich Roll?

  Are you tested before and after, right?

• 2:13:39Tim Spector?

  Yeah, so I was eating everything they had, so the baobab, the yam. But, you know, one day, it was porcupine was on the menu. So, you know, which is not something you get regularly. And various other animals that I had no idea what they were. They all got thrown on the barbecue. But you were surrounded by animals and dirt and there are the microbes as well. So I think part of this is also the environment that we've lost. As we've moved into cities, everything's sterile. You know, we're not, we need to go back to hugging trees and getting back to nature. And that's why gardeners have better microbes than non-gardeners.

• 2:14:20Tim Spector?

  You know, I think we also realize it's external as well as what we eat as well is important. But yeah, my microbes improved by about 30% in diversity while I was there. But when I got back on airplane food on the way back, by the time I got back to London, it had gone straight back to where it was.

• 2:14:40Rich Roll?

  Did you keep that culture, though, and store it for future proliferation?

• 2:14:45Tim Spector?

  Yeah, I wouldn't have got through the security.

• 2:14:54Rich Roll?

  Yeah, I mean, that conjures up the next thing, which is the future of fecal transplants. Like, it does seem like there's something interesting there. Like, if you can, the more we learn about the microbiome and the more we figure out how to kind of cultivate a very bespoke ecology for a particular individual, the idea of these fecal transplants seems to be a really good idea.

• 2:15:29Tim Spector?

  I think it's a great idea and but I would say that the hope and hype we had 10 years ago hasn't played out as much as I would have hoped.

• 2:15:41Tim Spector?

  It is the number one treatment for a couple of conditions, mainly really bad infections and something called recurrent C. diff, Clostridium difficile. You get recurrent diarrhea 30 times a day, usually caused by antibiotics overuse. That is 90% of the time cured by a single transfusion of a healthy donor stool sample. But there are not many other conditions where it's shown to be nearly as effective. And the early hope that it would be a cure for obesity has been shown to be false.

• 2:16:22Tim Spector?

  So you can't take someone's skinny feces and put them into an obese person and make them skinny. Doesn't work.

• 2:16:33Rich Roll?

  But isn't there, there's some indicia around cravings though, isn't there with this or no? Or autoimmune diseases?

• 2:16:42Tim Spector?

  Well, it does work in a proportion of people with ulcerative colitis, which is an autoimmune disease. So that's the other hope because there's this one disease where I think it's about one in four or one in five people have remission. So they, it's like there's no sign of the disease after it, which is pretty much as good as the drugs, the medicines, the immunotherapies that they're given, which is pretty good. But it doesn't work for other related conditions. Other autoimmune conditions doesn't seem to work nearly as well. So we don't really understand what it is. And it could be that, you know, the microbiome Of the host, the person who's, you know, the sick person has to be so bad,

• 2:17:26Tim Spector?

  there's literally nothing there in order for the new microbes to colonize and take over. And if it's too stable, it's really hard to gain a hold. Plus the fact we haven't matched up the donor and the recipient very well. And we don't know what the magic factors are. So I think there's still time to do it, but I think it's not looking as hopeful as it was. Perhaps 10 years ago to be, you know, the cure all for everything. But the exceptions to this are in cancer, where they've done a tale, a couple of cases of people who survived metastatic melanoma, responded very well to immunotherapy. And they took their, their stool sample and they gave that to people who'd failed

• 2:18:11Tim Spector?

  immunotherapy and were about to die. And a reasonable portion of them were rescued. Wow. So there could be very specific cases for people who have very bad microbes, where they just need that extra shot to, to, to improve them. So I think we're still finding our way and trying to get around this idea that because we're so different, it's very hard to come up with a sort of one size fits all solution. And they don't quite know whether to get 10 donors and put them all in a, you know, a magic mix and, and serve up that soup. Or they should be specifically looking for certain microbes.

• 2:18:53Tim Spector?

  Or you should be artificially producing these fecal transplants. And there are trials going, many trials going on artificially to look at it. But, so I think cancer is the one area of the most hope and excitement. And going out to the idea, I think in the not too distant future, everyone's going to be storing. They're still sampled, maybe to use when they have cancer treatment,

• 2:19:16Rich Roll?

  Mm-hmm.

• 2:19:17Tim Spector?

  Give themselves the best chance. And storing up the people who successfully fought off cancer against the odds and worked out what it is about those microbes that are so good at helping that person's immune

• 2:19:31Rich Roll?

  Yeah, yeah, yeah. Yeah, that's interesting.

• 2:19:33Tim Spector?

  Yeah. It's a nuanced game, as we say, but I think we were misled because a lot of people thought it was the cure for obesity.

• 2:19:41Rich Roll?

  Right.

• 2:19:42Tim Spector?

  That a lot of people were doing this on the internet and had some very bad results.

• 2:19:49Rich Roll?

  Uh-huh. Another source of confusion surrounds the importance or lack thereof of fermented foods. We talked about the 30 plants a week thing. I think there's a lot of people who think, as long as I'm getting some fermented foods in my diet on some kind of regular basis, I don't have to worry as much about the 30 plants a week or the diversity of the foods that I'm eating. How important is the fermented food piece? And then on top of that, how do we know that the cultures, the fermented cultures that are in these foods are actually efficacious?

• 2:20:32Rich Roll?

  We were talking about kombucha before the podcast, or in these yogurts, or these cafiers. It'll say, you know, it has this and that in it, but what is the pasteurization process? Like, do these cultures persist through the manufacturing and distribution process of these foods such that they have any kind of viability once they're consumed?

• 2:20:55Tim Spector?

  So, lots of questions there. I think the first one is, I think, to build a healthy gut microbiome, you've got to get the diversity of plants in there as your number one.

• 2:21:07Rich Roll?

  That's number one.

• 2:21:08Tim Spector?

  If you don't eat plants, I don't think any amount of fermented food is going to really help you because the...

• 2:21:16Tim Spector?

  Probiotic microbes in the fermented food don't actually stay in your gut very long. They pass through. And as they're passing through, they stimulate the other microbes to produce helpful chemicals. We don't exactly understand that because, but we know that the microbes, for example, in kefir or yogurt, these lactobacilli, they're designed to live in milk and yogurt, not in your intestine long term. So they pass through and they have to have a sort of collateral effect on that environment. They just, for reasons we don't still understand, they make them produce better chemicals. We discussed these pharmacy idea.

• 2:22:00Tim Spector?

  They're sort of boosting the pharmacy to produce those chemicals for you is the current idea of what they do. And obviously, the greater the diversity of the microbes that are doing that, the better your chance of it working. That's why kefir has more microbes than yogurt, perhaps 10 times more, different species. It's a more complex fermented food. And cheese, you know, often has only two or three microbial species, unless you get some exotic French ones, which often illegal in the US because they're too dangerous.

• 2:22:43Tim Spector?

  And then you've got things like kimchi, where the fermented food is, you've got the microbes which are eating the cabbage and the garlic and the chilies. And there may be 30 different microbes in there, including yeast and fungi. And the difference with those foods is that they're also prebiotic because you're also eating the plants that are nourishing the microbes. So they will probably hang around a bit longer than, say, just your kefir or your yogurt or your cheese ones. So, and the kombuchas are similarly complex, often between 10 and 30 different microbe species.

• 2:23:28Tim Spector?

  But how do you tell that, so you want to study, so little and often is the rule. So there's no point having a big, once a week feast, you want to have a small, little shots. And I think the study suggesting that if you can get three small portions a day, that's probably pretty ideal of different types of these fermented foods. And how do you tell what the best products are? It's really difficult. We were discussing kombuchas and, you know, I was in a store with Will. We were, we were looking at some of these range, great range of kombuchas in California. But some of them just at the bottom, just say, oh, gently pasteurized.

• 2:24:13Tim Spector?

  Right. So it's dead. So probably if it's a little use, although there is some evidence, there are some microbes that do work when they're pasteurized, but I don't think these ones have been proven to work. And so checking whether it's been pasteurized, checking it's the date, how long its shelf life is, if it's, if it's live, it's not going to have a really long shelf life. And so you pick up a kombucha, you want to see whether there's any sediment in the bottom. Is there something like a mini blob in there that's, that could form? And like, and similarly, other products, if you're taking kimchi or sauerkraut, make sure it's not in vinegar. It's actually live and it says live microbes on it.

• 2:24:57Tim Spector?

  Hasn't, again, make sure it hasn't been pasteurized even gently. And the ultimate test is probably to try some of these, either get a brand you really know and can trust. And if you don't know them, test them. You know, you can, you can take the sediment of a kombucha and if you put that into a bit of tea and sugar and leave it for a week, you'll know whether it's real or not. Similarly, if you take the end of a kefir, if it's live, it should, you pour it into a glass of milk, within 24 hours, that should have turned into kefir. So there are ways of actually doing your own little practical experiments to work

• 2:25:40Tim Spector?

  this out, but it's a real problem for the consumer at the moment. There isn't

• 2:25:47Rich Roll?

  Right, like the consumer shouldn't have to do that, you know, to figure this out. Like, we shouldn't have to run our own experiments to validate whatever's on a label or isn't.

• 2:25:55Tim Spector?

  And beware of artificial sweetness as well in a lot of these products, because we know they're harmful for the gut microbes as well. So you're doing some good and some bad. You might, you know, have to put up with a little bit of sugar, not too sweet, rather than having artificial chemicals, which will have a negative effect on the gut microbes.

• 2:26:15Rich Roll?

  And what about a proper probiotic, not as a replacement for a healthy, robust, diverse diet, but as something, as sort of a cherry on top. In the book, there's a study that you talk about with respect to COVID and kind of outcomes around, you know, populations that were on a probiotic versus not on a probiotic. So where's your thinking around that? Because there's also a lot of confusion and there's a wide spectrum of products out there. And I think a lot of consumers struggle to kind of make sense of that world.

• 2:26:53Tim Spector?

  Yeah, to cover the COVID stuff first, we did, again, a survey about a million people and looked at their COVID outcomes and whether we're taking vitamin supplements or probiotics. And actually, none of the vitamin supplements had a consistent effect on preventing COVID.

• 2:27:10Rich Roll?

  Right, the omega-3, the D, what else did you look at? Like, because there was a whole lot about like, if you're on D, you're going to be in good shape.

• 2:27:17Tim Spector?

  Vitamin C, garlic tablets, multivitamins. But the one that looked like it had the biggest effect was actually regular use of probiotics. This was an observational study, so it's full of potential biases and flaws. But, you know, for someone in gut health, and I'm biased to say, well, that looked like a good result for me.

• 2:27:42Rich Roll?

  Right, I'll put that one in the book.

• 2:27:44Tim Spector?

  But we did, a few years ago, we did a meta-analysis for the British Medical Journal and looked at all the evidence for probiotics. And there's absolutely no evidence that if you're healthy, probiotics prevent you getting disease.

• 2:27:59Tim Spector?

  Okay, so for the healthy person to take them regularly, probiotic capsules or however you take them, no clear evidence for healthy nor people they are useful. There's some evidence that in neonates, early young children and the elderly, they can be beneficial. So there's some randomized trials that show they are, some are good in preventing infections or other problems. They also are shown to work in, if you have, for example, some GI infections in balance, they do work. There's some evidence they work in mild depression in randomized controlled trials.

• 2:28:41Tim Spector?

  So there are a few examples where, and this irritable bowel syndrome is another common, there's some evidence they work a bit in these conditions. Now, many people they don't work at all, it's not totally consistent. And a lot of this is probably because each probiotic is different, they're protected by patents, so they can't be used by other companies, and our individual microbes are very different as well. So it's not surprising there's this big difference. So although we can say that many of these conditions probiotics work, I can't say which one you should take because the studies have included lots of different ones. So it's, but I think we're in a stage now where we're moving to the second stage of

• 2:29:26Tim Spector?

  probiotics. There's some exciting ones that have come out of this new science, because all these ones are very old we're talking about, all the ones you see out there. But there are some new microbes like Akamancia, for example, is a bug that is shown to reduce blood glucose levels in trials and actually works just as well dead as it does alive. And it's a very common feature in the new.

• 2:30:01Tim Spector?

  In all the new microbiology we're seeing. So I think the next generation are going to be much better and much more designed for human health than these old ones, which have just been around on some company's shelf with a patent for a long time. So I'm not giving you a very clear answer, but I think it's, I still think you're much better off taking your probiotics as food than as supplements.

• 2:30:26Rich Roll?

  Yeah, of course.

• 2:30:27Tim Spector?

  Because you're getting a bigger mix.

• 2:30:28Rich Roll?

  Yeah, of course, of course. And I appreciate the, you know, kind of respect for the complexity and nuance of all of this. Like, you know, our human brains want that clear cut answer.

• 2:30:41Tim Spector?

  We want a quick fix.

• 2:30:41Rich Roll?

  Do this, don't do that. Yeah.

• 2:30:42Tim Spector?

  Give me the tablet.

• 2:30:43Rich Roll?

  And you're like, ah, not so fast. You know, even with each one, like everything in this book, like, you know, there is that layer of complexity that I think when you read it, you begin to understand like why it's so hard to even tackle this subject to begin with. Like, how many years did you spend writing this book?

• 2:31:01Tim Spector?

  Six years.

• 2:31:02Rich Roll?

  Yeah, so.

• 2:31:02Tim Spector?

  I realize why no one else had done it.

• 2:31:04Rich Roll?

  And it's almost, in this day and age, a courageous act to like dip your toe into the world of nutrition and make a statement, you know, because, you know, it is, it is, it is so difficult to provide kind of any actionable, you know, guidelines around it because the, the science is, you know, is in many ways so inconclusive and there's so many variables that come into play, like, you know, in terms of, and the personalization, you know, aspect of it that is emerging that makes it even harder to say, you should do this and not do this. Right? But we do have to end this podcast. So maybe we could do

• 2:31:43Rich Roll?

  that with, if there are any kind of concrete, you know, rules or recommendations for the person who's, you know, brand new to the idea of the microbiome even being a thing and who's grappling with the idea of making, you know, healthier choices for themselves, you know, beyond the 30 kind of plants a week, what are some other principles that you could share? Because at the end of, you know, the chapters, you do kind of like bullet point, like here's some, here's some kind of clear takeaways that I think would be helpful. So top of mind, you know, what sits atop the kind of most important of those?

• 2:32:23Tim Spector?

  Well, we've covered some of them. So obviously, eating the rainbow is, you know, the colors are there for a reason, and they're actually really good. So, you know, don't eat beige. Don't eat beige. Yeah, go colorful. That's the, that's the title of this podcast. Go bitter. Many bitter things are actually good. You know, one reason coffee's so healthy for you is it's got, full of polyphenols and, you know, recommend coffee over orange juice anytime as a health drink. Should be in the health section. Dark chocolate's another surprising one. Cook with extra virgin olive oil rather than any other oil. Don't believe all this nonsense about. Heating points? Yes. Yeah, you go into that as well.

• 2:33:07Tim Spector?

  The way you eat is also important. So, we, you know, we've, we've talked about what to eat, but time restriction eating, we've discussed. We didn't discuss that actually has a really big benefit on your gut microbes. So, all the studies show that if you leave a big gap overnight, so your, your gut is rested, just as the hunter-gatherer tribes did, you know, they're, they're not nibbling snack bars or protein bars at night. They're, you know, they're resting just as they're sleeping, giving that full circadian rhythm. Real chance to real synchronize. So, I think that's, that's an important part. So, there's

• 2:33:50Tim Spector?

  reducing the snacking time, less meals, giving yourself, you know, at least 12 hours overnight, ideally 14, is a good way for your gut to, to repair itself and enhance. Eating more slowly. We all eat too fast. I think one in five American meals are consumed in the car. You know, it's difficult to have a leisurely meal in the car. Just, you know, wait. Do like the Mediterranean countries, you know, just don't have snacks, wait and have a proper meal, you know, make it a social good occasion, enjoy the food. And, you know, learn to try something new every.

• 2:34:37Tim Spector?

  Every week you should be aiming for something new as extra. So part of this thirty plants is to discover new things you haven't eaten and, you know, get your taste buds to try something new all the time and introduce that to your family and make food something exciting rather than a chore because we all get into these ruts in our choices. We find something we like and we think it's healthy. We have the same thing. Well, our microbes don't like that. They like to be tested all the time. So I think it's all about an adventure, experimenting. Find out whether you're someone who does well, you know, with this long overnight fast and not snacking or whether you are someone who does need to eat. There are different people.

• 2:35:21Tim Spector?

  Are you an early morning person, a late morning person? Try skipping breakfast. Try changing your breakfast for, you know, from a high carb one to a high fat one. See how you feel. Try and just think about how your body's working. Don't accept that everything's the same for everybody. And I think the more we can all experiment and understand our bodies, the better we get to understand food and live with it. And always think about your food now, again, in these food choices. If you care about the planet, really think about those food choices you're making because as an individual, it is the number one thing we can all do to save our planet.

• 2:36:00Rich Roll?

  Beautifully put. I really appreciate it. Final thing before I let you go would be around the kind of science that you would like to see being performed right now. Like what is the study that hasn't been done yet that you feel is most important to be conducted? And what is kind of on the nearer horizon for Zoe and the research that's going on there that has you excited?

• 2:36:29Tim Spector?

  Well, in general, the study that will never be done would be a massive randomized control trial of ultra-processed food against real food. And pay people to do this. Why can't we do that? Because... Who's gonna fund it? Who's gonna fund it? We already know the answer, though. Irrationally, the Ethics Board would probably say it's unethical to randomize one arm to the American diet and the other arm to a healthy diet. But that's what we need to shake this up. So far, the study's been limited to a few weeks. And that's where I think I would...

• 2:37:12Tim Spector?

  If all the money nutrition do that study, that would change our system and show how bad it is for us. The Zoe studies are... It's evolving all the time and introducing all kinds of new features and giving people personalized feedbacks on whether they're dippers or not. Should they be worried about giving... We're trying to move towards giving people real-time advice about what they should be eating. We are just starting retesting, so this is a really exciting time.

• 2:37:52Tim Spector?

  People can see if they've reduced their sugar peaks and their fat peaks and they improve their gut microbiome. What does it look like on retest and how their gut microbes are tested and the results are looking really good on that? Because no one's managed to do that yet so far. And so using the gut microbiome is a pretty good sort of like your dental checkup that you go to every six months or so to say, "How am I doing?" When I'm experimenting, it's quite hard to know. I think we're gonna start doing these citizen science projects within... Within the Zoe product, so that we'd love so a thousand people to start, you know, go on fermented foods for a month and see what the difference is.

• 2:38:35Tim Spector?

  Others, intermittent fasting, all these lifestyle interventions, I think, would be really exciting and we want people to join in this big community. So there's a lot, there's so much stuff going on as well as feeding back these new insights into the microbiome, maybe getting some of those microbes into as new probiotics and prebiotics, because they've never been discovered before, but they have really big effects. In our data now, we see these huge effects of these microbes don't even have names yet. And so if we can harness them, you know, they could be super powerful medicines as well. So, yeah, there's sort of too much to, I'm, you know, a kid in a sandpit that's full

• 2:39:20Tim Spector?

  of toys and it's a fantastic time to be doing science.

• 2:39:24Rich Roll?

  Yeah, yeah, well, I can tell it lights you up and it's a really fascinating, new kind of emerging field. Like if I was a young medical student, this would be where I would want to, you know, be focusing on right now because you're at the very beginning of something that clearly is only going to grow and become kind of more integral to all aspects of human health and planetary health too. So it's really exciting and I think the work you're doing is really important. It's inspiring and it was great to talk to you today. So thank you, appreciate it.

• 2:39:59Tim Spector?

  It's been fun.

• 2:40:00Rich Roll?

  Yeah, it was good. If you want to learn more, pick up Tim's book, Food for Life, The New Science of Eating Well, you can check out the Zoe app.

• 2:40:09Tim Spector?

  Joinzoe.com.

• 2:40:11Rich Roll?

  Joinzoe.com. And any other places you want to direct viewers and listeners?

• 2:40:18Tim Spector?

  Follow me on Instagram. People still do that?

• 2:40:23Rich Roll?

  They still do. I think they still do. You're not on TikTok?

• 2:40:29Tim Spector?

  I wouldn't admit to it.

• 2:40:31Rich Roll?

  There we go.

• 2:40:32Tim Spector?

  No, I'm not on TikTok. I can't. I haven't got the patience or technology for that.

• 2:40:38Rich Roll?

  Yeah. How's Dr. B doing? Is he doing a good job? Should we give him a review right now while he's sitting right here?

• 2:40:46Tim Spector?

  Yeah, no.

• 2:40:47Rich Roll?

  You gonna fire him?

• 2:40:48Tim Spector?

  No, he's nine out of 10. Nine out of 10. He just needs to bring more sunshine to the venues when he listens.

• 2:40:55Rich Roll?

  Yeah, good, man. Thank you. Well, come back again and share with me more about what's happening. Because I'm sure it's changing all the time, right?

• 2:41:05Tim Spector?

  Oh, yes.

• 2:41:06Rich Roll?

  Yeah. Cheers. Thanks. Peace.

• 2:41:22Rich Roll?

  That's it for today. Thank you for listening. I truly hope you enjoyed the conversation. To learn more about today's guest, including links and resources related to everything discussed today, visit the episode page at richroll.com, where you can find the entire podcast archive, as well as podcast merch, my books, Finding Ultra, Voicing Change, and The Plant Power Way, as well as the Plant Power Meal Planner at meals.richroll.com. If you'd like to support the podcast, the easiest and most impactful thing you can do is to subscribe to the show on Apple Podcasts, on Spotify, and on YouTube, and leave a review and/or comment. Supporting

• 2:42:07Rich Roll?

  the sponsors who support the show is also important and appreciated. And sharing the show or your favorite episode with friends or on social media is, of course, awesome and very helpful. And finally, for podcast updates, special offers on books, the meal planner, and other subjects, please subscribe to our newsletter, which you can find on the footer of any page at richroll.com.

• 2:42:31Rich Roll?

  Today's show was produced and engineered by Jason Camiolo with additional audio engineering by Cale Curtis. The video edition of the podcast was created by Blake Curtis with assistance by our creative director, Dan Drake. Portraits by Davy Greenberg. Graphic and social media assets courtesy of Daniel Solis, Dan Drake, and A.J. Akpodiette. Thank you Georgia Whaley for copywriting and website management. And of course, our theme music was created by Tyler Piot, Trapper Piot, and Harry Mathis. Appreciate the love, love the support. See you back here soon. Peace. Plants. Namaste. [music]