Tim Spector: That's where we are now and it's all falling apart and the reason that was people love the simplistic approaches, you can then whack it on the label and say free from that, low in that, buy it, it's healthy. And it doesn't matter what other crap is in it, it will sell more to the gullible public who, like doctors, are very poorly educated about what they're eating.
Dr Rupy: Is everything we have been told about nutrition potentially wrong? And have we questioned prevailing dietary dogma enough? Are we asking the right questions in nutrition science? And if not, how do we rectify it? Professor Tim Spector, professor of genetic epidemiology at King's College London and honorary consultant physician at Guy's and St Thomas's Hospital is my guest this week and we dive into these questions and a whole lot more. He is the lead researcher behind the world's biggest citizen science health project, the COVID Symptom Study app. This free tool has been used by more than 4 million people in the UK, US and Sweden, and the app has also identified new symptoms of disease and risk factors as well as monitoring progress to warn health authorities. He's also published four popular books, including the best-selling Diet Myth, which I absolutely love, and more recently, Spoon-Fed. And I think it is absolutely fantastic and that forms the basis of our discussion today. On the show, we chat about why the calorie in, calorie out dogma is entirely flawed. And I honestly, this is one of the commonest questions I get asked and it's quite frustrating that people still rely on a calorie in, calorie out paradigm. Why salt may not be the prime suspect, quite a controversial area, but something I think warrants a lot more attention as Tim has given. The approach to pesticides that we should take, and this is something that we've discussed on another podcast with a farmer from Chile. So if you're interested in that, I would definitely take a listen to that podcast episode as well. Artificially sweetened beverages, practical suggestions on how to live healthier, and what the future of personalised nutrition could hold. Like I said, Spoon-Fed, fantastic book, definitely go check it out. The links of which are on the podcast show notes page. And I'd encourage you if you are interested to read the Predict 2 study. It's one that looked at dietary differences and responses of the individual to different diets. It's a fascinating read, something that was published in Nature in 2020. The link to which I will make sure I put on the podcast show notes. Make sure you join up to the the mailing list, the mailing list where we give evidence-based recipes every single week and we focus on the quality of food rather than the macronutrient composition of food, something that we discuss in today's podcast episode. I hope you enjoy it and I will summarise our discussion at the end. I wanted to first introduce you to the listeners who may not know about your background. What was your experience in medicine? What's your specialty and what led you to nutrition in the first place?
Tim Spector: Okay, it sounds an easy question, but it's a very long answer. So I'll try and keep it short. So, I trained in medicine and I always had an interest in research and I got interested in epidemiology very early on as a medical student. But I became a physician and took a year out to do a master's in epidemiology at the London School of Hygiene and eventually then chose a specialty of rheumatology, mainly because it didn't involve many nights. And my consultant said, it's a great specialty to be in, Tim. In six weeks, you can learn it all and the rest is just psychology with the patients. So that appealed, that sort of self-deprecating side of the specialty as opposed to cardiology and all these other pretentious areas that told you how incredibly difficult it was. So I became a consultant rheumatologist doing as much research as I could. And I set up various population studies, one in East London, a place called Chingford, and then soon after, and just as I got my consultant job at St Thomas's, I had set up the twin, this big twin study of, which was to become the UK's biggest twin study of adults and been running that ever since for the last, you know, over 25 years. Which allowed me to then after about seven years, slowly switch over from the from NHS to university. And then I studied twins for a while. Well, I still study twins, but I was interested in the genetics, nature of nurture, which was very novel at the time because everyone said it was all due to ageing and that wasn't anything to do with your genes. So we disproved a lot of myths that way. But I guess about 10 years ago, I started being more interested in why identical twins were different and what the environmental factors were and why would identical clones get different diseases, which they often do and die at different times. And that led me towards the microbiome and the fact that identical twins often have very different microbes. And that led me to really re-look at nutrition. And every time I write a book, I I managed to get a sabbatical and just immerse myself in the literature in a very nice place, usually, you know, sunny Barcelona or somewhere like that. Where I was just free really to look at a whole the subject again with fresh eyes and retrain myself to be an expert. So I've reinvented myself many times as a doctor. And so it's very hard to know what I am, whether I'm a some people call me a geneticist because I had to teach myself that when I did the twins and we did all kinds of gene discoveries. Genetic epidemiologist, and now, you know, I've sort of become a gut health expert and nutritionist. And it's there's always a bit of difficulty when you first move into a subject because people don't like, you know, people who aren't insiders coming in and and and working on it. But after a few years, they've forgotten and you just keep moving on. So that's that's where I am. So, so I'm really still fascinated. Although I have a short attention span, I think there's so much exciting work to be done in nutrition and gut health that I'm not planning on changing anytime soon.
Dr Rupy: I think it's a really nice sort of way to develop your career as a medical professional by going through different specialties and just teasing out where your interests lie. And I think a lot of people would love, particularly those in the medical profession, to almost be like a chameleon, a jack of all trades by trying their hand in your case at rheumatology, epidemiology, doing research, genomics, and now being led to nutrition. I think that's a really nice way of sort of planning out your career, even though I'm not too sure if that was your intention.
Tim Spector: It's much harder to do it now for someone junior than it was for me. Everything's now planned and you've got you go on these long rotations and you can't get off them and you know, it's like people just don't like the idea that you might change. And I think it's completely counterintuitive because more than ever, we need multidisciplinary people who can think across, you know, different areas and bring expertise from one to another. And we simply don't have the the system in place really, unless you're really brave. So, you know, I would still urge people to be brave, but they've got to, you know, they got to take some risks and, you know, and you've got to be thick-skinned because, you know, I was told, what what are you doing at this conference? You know, you're not a I don't know, you're not a geneticist in obesity, or what are you doing this conference? You're not a, you know, you're not doing the genetics of psychology or, you know, and then the same with nutrition and the microbiome. You have to learn the new language and you have to feel stupid for a bit until you get it. But it's I think more and more people should do it and definitely that that's the only real way medicine's going to move forward, I think.
Dr Rupy: Absolutely, yeah. I think you've got to be comfortable being junior whenever you try something new. I mean, I'm constantly being told to stay in my lane as a general practitioner, going to emergency medicine, doing nutrition, you know, learning about the microbiota and its impact on various parts of our health. I think it's it's definitely the mindset of someone who's new to nutrition and wants to learn more, you just got to be comfortable being the stupid person in the audience.
Tim Spector: Yeah, and I think I was I was helped because early in my training, I I did a European exchange and I went for a year to Brussels. And I I could speak French enough to order a meal in a restaurant, but when I was given sort of 15 patients to look after on day one, it was the deep end. And so for three months, I was treated like an idiot. And so I think maybe that that hardened me up for later life, but I didn't actually mind because it was great and, you know, I now speak fluent French and it was, you know, a great experience. And I think everyone's just got to go through that, realise you can come out the other end a stronger, better person, as long as you don't mind, you know, stupid people saying you're stupid, which I guess a lot of foreigners get that in different countries as well, but I think it makes you tougher.
Dr Rupy: Yeah, definitely. I want to talk about the differences between your the book I first came across with you, even though you've written four, The Diet Myth, and what the difference is between The Diet Myth and Spoon-Fed. And and and if there's been any change in your thinking around nutrition in that time period. I think I think it was about five years between the two books.
Tim Spector: Yes. Well, as you know, when you write books, they they take a long time to from conception to birth. And so, you know, nearly as soon as you've sort of one's on the shelves, you you've got to start to think about the next because it takes so long. But it's interesting because I was asked to I'm writing a new edition of The Diet Myth, which is going to come out in the end of the year, actually. And so I had to reread it and said, well, what would I change? You know, what's what's changed? Because I expected to rewrite quite a lot. And interestingly, most of the ideas that I put in there, some of them speculative, I did most of them have stood the test of time and actually got stronger. I don't think any of them have turned out to be the bullshit that a lot of the naysayers said, you know, a lot of my colleagues said, oh, you know, microbiome is just one of those fads. No one will have heard of it, you know, in five years time. Don't give these guys a grant, you know, it's a waste of time. Generally because they weren't doing it and they didn't understand it. But often these people in the UK are in a position of power and authority and so can squash that whole field. But looking at it again, really I didn't have to make any fundamental changes to it at all. It just added more evidence building on what we'd found. And I think it's just got stronger and stronger really about the the importance of the gut microbiome in our health. And more and more people are now measuring it. It doesn't seem as weird to talk about kefir and kombucha as it was five years ago. It's now in, you know, most supermarkets and people now seeing it and that's great. And I think the, you know, people have moved beyond it just being about probiotics and do understand gut health much better. So the the bits that have perhaps changed are the personalization side of things. So I think we've got better at measuring the microbiome and we realise that actually we're still scraping the surface in terms of the function of these bugs. And yeah, we got a few of these, you know, we got a bit excited about particular species five years ago and some of those haven't panned out. So things like the Christensenella story, which was the bug that we wrote the paper on in Cell that you can when you put it into mice, you could, you know, keep them thin. It looks like when you really deeply sequence that bug, it was probably a different strain than the one we thought it was and it might be a group of bugs acting together rather than one on its own. So in a way, the area has just got more complex rather than sort of simple, but it didn't mean it was wrong. It was just we were sort of just scraping off that first layer of paint on the door. I think that that's the way I would see it. So, yeah, I'm pleasantly surprised compared to some other fields I've dabbled in like epigenetics and, you know, other genetic fields about how much has stood the test of time. So Spoon-Fed really focuses more on the personalized nutrition, the fact of how unique we are, which I don't think we really knew five years ago. And also, I think it brings in in discussing a lot of these these food myths, I think the sort of element wasn't discussed before is about how that that myth evolved and the influence of both, you know, nutrition, the nutrition world itself, the academics and the food industry and the grant funders. And I think and of course, you know, the big advertising companies above it all. I think that was the sort of new bits. Plus, you know, some bits of medicine are changing and so I wrote a a chapter on salt. And I'd looked at salt five years ago, thinking, oh, I wonder if this is really real. But I because I I had some when I was ill, my blood pressure shot up and I did try going off salt and I thought, you know, but there was nothing really I could say that was wrong about the data, but now I could. So, you know, that's that is the good thing about medicine is that if you look hard enough in certain areas, people are happy to do the papers to question previous research because that but that's really because it's all not it wasn't a nutrition-led study, it was all about it was about the cardiologists and the renal physicians and the diabetologists worrying about giving too little salt to their patients and them getting worse.
Dr Rupy: Yeah, yeah. Well, I was going to say, this book is particularly brave, I would say, because you're going systematically going through different nutrition sort of dogmas that are ingrained into everyone's head, saturated fat, calorie counting, even sugar. And salt, I found was a particularly interesting chapter because you talked about the unnecessary aspect on one aspect of diet rather than looking at overall diet quality, which I I imagine is a proxy for the entire book, really. I mean, that's the overall overarching message I get is that it's about overall diet, it's about looking at a holistic way rather than just specific aspects of food. What was sort of the trigger for you to think about, okay, salt isn't as dangerous as we've been led to believe? And how would you explain that to sort of the the wider population that, you know, is constantly obsessed with salt reduction in in what they eat?
Tim Spector: Well, there were a number of sort of key events that made me change my mind. I guess the first was the realisation that all these studies talk about average levels. And whether that's significant or not. So there's this this big difference between how it affects a population and how it affects you. So I took the personal approach because as I said, I was trying it myself. And I couldn't notice any difference with me taking my own blood pressure, you know, having sort of two or three weeks of really disgusting food. So I and I thought, is it really worth it? Then I started looking at it and it turned out that if you're, you know, for the average person who's not of African origin, doesn't have any other major risk factors, you know, it's going to change it by one to two millimetres. Okay, so to go through life, never going to a restaurant and having all your food tasteless and bland for the sake of, you know, less than, you know, 1% improvement in your blood pressure, which, you know, was trivial compared to the, you know, tablets, seemed me not worth it. And then I looked at the other data and it there was this new stuff coming out from some of the developing countries that actually, you know, this association with salt didn't hold at all. And there was other data from patients with diabetes showing that people on salt-restricted diets were actually getting more heart disease and more kidney disease. So it was actually harmful to them. So the whole thing really to me suddenly fell apart. Once you realise, A, how little any one individual gets out of it unless you are perhaps in, you know, these this one in 10, one in 20 people that is quite sensitive to salt, most people are suffering without much gain. And I think that was the sort of key key point there. And it's an interesting one, you know, because I was brought up in epidemiology by a famous epidemiologist called Geoffrey Rose, who said the whole point of public health is to just shift that curve slightly. Which you can understand if it doesn't, you know, affect your life. But to my, you know, anyone who likes food, will know that salt is crucial. It's very hard to cook good meals with zero salt. And it's it's very hard to enjoy life never going to a restaurant or eating out where the salt is already added to your the food by the chef. So, so these things start, you start to weigh up these these ideas, this dogma, right, salt is bad. And then also, you know, everyone knows that it's not about the salt you add to your food, it's generally people who have really high salt intakes are eating low quality ultra-processed food that, you know, in ready meals, etc, and frozen pizzas and that's the problem, not the salt.
Dr Rupy: Yeah, yeah. To contextualise that for for people, I I guess, you know, in that chapter, you talk about the issue, the main issue with salt intake being its inclusion in ultra-processed foods, which kind of litters throughout the whole book as the one of the biggest issues that we have to contend with, rather than, okay, it's okay to sprinkle salt all over your, you know, masses of meat that you eat every single day and everything else. I think, you know, it really pertains to the entire diet quality rather than just the salt itself. Is that fair to say?
Tim Spector: Yeah, well, exactly. It's it's a good an example and there are many in the book of how in the past, because we didn't really understand nutrition, we've picked on one ingredient and that has been the deadly one. And then it's nice, it's a nice simple story then to say we've got one villain, whether it doesn't matter whether it's gluten, whether it's, I don't know, you know, lectin, whether it's, um, uh, it's, uh, saturated fat, um, you know, whether it's, uh, something in eggs or, you know, you you name it, it's some particular chemical or E number. And we forget that food is now made up of 26,000 chemicals at least. And so every time we eat, you know, just a carrot, we're eating hundreds of different chemicals that are mixing with our saliva that has hundreds of different chemicals and then our microbes that produce, you know, tens of thousands of chemicals that mix with our 20,000 genes and, you know, it is not something that can be reduced down to, you know, one thing that is the problem with our diet. And that that's where we are now and it's all falling apart. And the reason that was people love the simplistic approaches, you can then whack it on the label and say free from that, low in that, buy it, it's healthy. And it doesn't matter what other crap is in it, it will sell more to the gullible public who, like doctors, are very poorly educated about what they're eating.
Dr Rupy: Yeah, absolutely, yeah. And I think, um, uh, on the subject of that, we are quite binary people. I feel like we just like to have everything simplified, whereas nutrition is incredibly complex as you just described with the number of different chemicals and the number of different pathways, a simple humble carrot can influence on its ingestion. And on the subject of chemicals, um, you talked about artificial sweeteners in one of your chapters, which I was really interested in because I'm constantly asked about the safety of artificial sweeteners, the impact on the gut microbiota, and whether we should be accepting of these novel chemicals in our food system. What are your thoughts on that?
Tim Spector: My thoughts are I've always been suspicious of the artificial sweeteners. Well, not always, actually. I used to drink diet Cokes and diet Pepsis 10 years ago, thinking they were much better for me. And they undoubtedly are better for your teeth. Okay, so if you've got some young kids addicted to this stuff and you can't get them off, at least you've stopped their teeth falling out if you switch them over. So that's definitely something better. But looking at all the trials in kids and adults where they switch people from regular, these regular sodas to diet drinks, all the meta-analysis show no benefit in terms of weight loss or diabetes. So that is weird, right? And the average person, average kid or adult was swapping two cans a day. So each can, I don't know, has 130 calories or something. So we're talking 260 calories difference and no observable difference in weight or sugar in about 20 studies summarized. So it's clearly, it's not neutral. You know, if it was just water, you'd expect some benefit. And of course, they never really tested against water. None of the companies want to do that, so they won't pay for it. They want to, you know, they will test it against these other ones. But, um, so the first of all, you know, you've got to think it must be doing something else bad to the body, otherwise, you know, you'd get some benefit of of these free, you know, zero calories or virtually zero. And so that's where these chemicals which all act differently. So it is hard to, they don't all work in the same way. And it could be that some people react with one and not the other, but they do interfere with your gut microbes because most of them are derived from petroleum and various other bits of carbon and industrial processes. They're not something that are with the exception of stevia are actually in plants. And even the stevia we drink isn't is only produced as a small fraction by plants. So we think that they're interfering with the gut microbes. The gut microbes can't break them down. And they're like just like hitting this, I don't know, like trying to swallow ball bearings or something alien, some crystal that your body's never seen before in, you know, despite millions of years of evolution, and sends off some other signals to the body that maybe increase inflammation or send increased appetite signals because of the sweetness, or do other things that are not neutral. And there is evidence they do reduce the diversity of your gut microbes as well. So I think generally it's a chemical that your microbes are not used to and maybe doing us some harm. And so I do worry that we're switching from one evil to another. And this is sanctioned by the government with the sugar levy that without really proper studies. And, you know, it is amazing we're not doing really large scale studies of this. If it if it was a pharmaceutical, we'd have spent a billion pounds on this already to see if it was safe. But we introduce new chemicals in food all the time with very little in the way of safety checks and no long-term follow-ups or anything.
Dr Rupy: There's a couple of things there that you mentioned that I really want to pick up on. One, in that despite the low calorie or the lower calorie content of the diet, sweet beverages, there wasn't any difference in weight loss. And the second is, how do we approach new artificial sweeteners that are invariably going to come onto the market in the future that may be shown to have lesser effects on, um, blood glucose, as there is a there is a new one on the market, I think that's been added to a sugar cereal that's been shown to have lower impact on sugar levels and thus being marketed as a healthier alternative to sugar. How should we approach artificial sweetness? Should we use the the um, guilty until proven otherwise sort of approach or are there reasonable things that we can do to introduce it safely into the food system before?
Tim Spector: No, I mean, I'm not I'm not against them per se and it could be that these new formulations of stevia, for example, which they've grown, stevia was introduced a bit too early and about one in four people got a really bitter taste with it. So they had to reformulate it and grow up the different form of it, chemical form, which is grown in vats by microbes actually, ironically. So they're producing this special form of stevia that doesn't have the metallic taste because they couldn't grow enough of it to be, each can would cost about 10 pounds. Um, so that's that it's possible that has less effect on the body and I'm not against that. But what I would like to see is that someone's actually done in the same way if you introduced a new drug that affected the gut, um, that you demonstrated it that, you know, in 100 people followed for a year, there were no real abnormalities shown and that it was fine. So I just think we need to, you know, I'm not against food innovation at all. But I think the fact we virtually have haven't changed the way we test foods and chemicals in 50 years, we just stick it into rats and see if they get liver cancer. You know, that's basically it in massive doses. And it's like so so outdated. You know, we have the microbiome, we have fabulous genetic sequencing now. We can see exactly what's going on. So they should prove it's safe, not ask us after the event, people like myself, you know, with no funds to try and raise the money to try and prove them wrong. And that's that's where this whole field has got out of out of sync. And you know, and the food industry will commission papers questioning research like ours we've done or others, other groups like the Israeli group with the Weizmann, just sowing seeds of doubt because the studies ideally are, you know, should be bigger and and more powered, as if it's, you know, the owners should be on us to prove without any doubt that they're dangerous rather than these companies doing it the other way around. So that's what needs to change.
Dr Rupy: Yeah, I I totally agree. I think, you know, before you essentially run experiments on a large public, um, on a large public scale, you know, we need to have reasonable evidence to suggest that they are safe and they're not going to have downstream effects that we only realise a year or two into, um, after, you know, it's been introduced. Um, you mentioned calories there and you've done a whole chapter on calories and the myth that, uh, calories in is sort of the be all and end all and can accurately predict weight loss if you just control your energy intake. What are your overarching thoughts about that now?
Tim Spector: I think it's a complete con. You know, I'm not a calorie denier. I think they do exist, right? It's it's uh, but it you know, if you burn food in a calorimeter, you will get heat and it will raise the temperature by, you know, one degree. But, um, you know, as a as a tool that you can use for weight loss, it's ridiculously overrated. Um, you know, speaking in the last 10 years to nutritionists, dietitians, specialists in this field, they can't measure it accurately, right? So give them a week to say, okay, tell us how many calories you're intaking, even they, you know, and you'd have to use scales for every single time you did it and it's just impossible. So if you then rely on what's on the label, you're also running into other problems. Uh, tests show around 10% error on these labels, which is quite legal. And some foods have up to 20% error on it. So traditionally we've, you know, we under we overestimate the calories in nuts by 20%. And also we treat the calories the same, you know, whether it's the whole nut or whether it's ground nuts or whether it's whole chickpeas or it's hummus. And of course the food matrix is absolutely crucial to what changes. Then it gets even worse because, you know, we've now got this legislation about restaurants and fast food showing the labels. In America, they've been doing this for the last five years, hasn't really changed the waistline of Americans. But they have shown that how the portion size is so variable that it makes a nonsense of that calorie estimate. So, measuring it in and it also, you know, why do we have 2,000 calories for women and 2,500 for men? You know, who who is Mr and Mrs Average? And, you know, where do they live? What what and so, you know, I tested myself on a metabolic chamber and, you know, if I was eating 2,500 calories, um, you know, I'd have to be doing about 900 burning off 900 calories of exercise every day to to stay stable. So it it's a nonsense. And we've shown that many now experiments have shown that if you give identical calorie meals, one of fat, one of carbs, you'll get a different result. Um, you know, people process them differently. And this all comes back to this individuality that nobody is average. So, but so my my main problem with it is, you know, yeah, I can see there are some, you know, there's companies formed on it and there's many practitioners doing it and Weight Watchers is, you know, you're fighting a billion dollar industry who love the calorie. Plus you've got all the food manufacturers who love to put low calorie on the packet. And when people see that, that's all they see. They don't see the other 30 ingredients, the nasty stuff that, you know, has been added to improve the the feel of it, and and it also gives people, you know, license to perhaps eat more of it, as several studies have shown, they will eat more of it. Oh, you know, this is a low fat, low cal snack. Oh, I can have twice as much. Um, and it doesn't fill you up as much, you know. Um, so that input side is really bugs me. But of course, that's even less compared to the out side, the other side of the equation, how much do we all burn? We all burn hugely different amounts and it's really difficult to measure precisely. So we've got no idea what the input should be because, you know, the output is so different and we know that and the whole equation calories in equals calories out is biased because that assumes they are independent. You know, any equation really means the two sides are independent of each other. And if and but if they're interrelated so that, um, you burn more calories with exercise, for example, um, you know, that has a feedback loop to to reduce your outputs. You'll slow down your metabolism. And so the whole thing, yeah, you know, and I think we have to knock that on the head first because everything else then falls over after it. This sort of dumming down food into one magic number. Oh, you know, do you realise a croissant has, you know, 210 calories? Well, you know, why don't you have this, you know, ready meal that only has 199 or something, you know? And avocado, you know, deadly, you know, because it's, um, it's got, you know, calorie dense fats in it. It's so outdated. It's so, you know, it's 100 years old concept that we just haven't managed to shake. And I think it completely deflects from the quality of the food argument. And that's what really we're trying to do now and that's, you know, trying to use our research to get people to lose weight healthily is really to get them to focus on different ways of eating and ignoring the calorie the calorie count of the food. And I think we've got we've got some studies going in the US now, you know, with Zoe and it is showing to be successful. And we never never mention the calorie counts of the foods and things we're suggesting.
Dr Rupy: Yeah, I I totally agree. I mean, this is part of the reason why whenever I've written cookbooks or whenever I post recipes online, I negate to include calorie counts because I don't feel that that's a good reflection on the quality of food because quite frankly, if people knew the calorie count of some of the food that I suggest, which has lots of good quality oils, nuts and seeds, it will far exceed what you'd find at something like a Weight Watchers or another diet, um, ready meal. Um, and I think it gives a false sense of security as well to the consumer that just because this is a low calorie option, this is one that I should choose. And like you said, it, you know, it doesn't give an indication of the overall diet quality. And some of the things that you suggest in the book about the amylase producing enzymes, the length of digestion or your digestive tract, the absorption from food, the timing of ingestion, all these different things will have an impact on the intake of energy from what we consume.
Tim Spector: Yeah, no, I think you've got it right. You know, we should be judging food by seeing what's in it. Does it taste good? You know, is it the right time to eat it? You know, are you hungry? You know, um, and in a way, the last thing is, you know, it's calorie count because that's been so manipulated by by the industry as well. Um, you know, and most of us know the difference between, you know, a cake and a bit of spinach, you know, that there's more calories in one than the other. Um, okay, I think it was initially helpful to show that some of these ready-made sandwiches and things, you know, had enormous amounts of calories in them that people didn't realise. So I'm not saying it had no value when they first started being introduced. But people have got to just realise that anything you buy ready-made with some, you know, tasty sauce to make you eat more of it is likely, if it's not high in calorie, it's likely to be high in various sweeteners and um, and flavour enhancers to do the same, to do the same thing. And, you know, you question whether you want that kind of food regularly.
Dr Rupy: Yeah. And it also deflects responsibility from the food manufacturer away from themselves and just saying, well, to the consumer, it's because you didn't output, it's because you didn't expend enough energy by exercising. And I know exercise is another chapter in your book that you've talked about a lot. And uh, rather than go through every single chapter in the book, I want everyone to to read Spoon-Fed because it's a fantastic read and I think it really does set the scene of nutrition as it is today, explaining why we're in the current environment we are and what things that we need to focus on going forward as well. Um, I wanted to talk about, uh, pesticides. Uh, this is something I'm constantly asked about and um, I mirror a lot of uh, the arguments that you made in the book, uh, about the again, pragmatic principle. Um, but I I wonder what your thoughts are on pesticides and whether people should be choosing organic and how you personally choose to eat as well.
Tim Spector: Yeah, we did we did a small study in my department and it was rather worrying because it did show that um, uh, healthy vegetarians had higher levels, you know, in their blood and their urine of pesticides.
Dr Rupy: Interesting. Interesting. Okay.
Tim Spector: So, yeah, so, um, so I, um, I try, I I try and buy organic, uh, most of the time for my regular produce, but I I don't go, I don't freak out if I can't. Um, and sometimes, you know, if it's if it's four times the price, I do bulk at it and say, well, I'll just, you know, have some other good food as well that isn't, you know, hasn't got pesticides on it to counteract that. So, um, I would only really be, I'd be more worried if I was female and pregnant. I think that's when I would pay more attention, um, more than I do at the moment. I would try and be a bit stricter, but I think otherwise, you know, we've got to be pragmatic, you've got to enjoy food, it mustn't be fearful. And my view on pesticides is they're not a they're not a good thing, but I don't think, you know, it's something that might occur gradually over 10, 20, 30 years. Otherwise, we would have noticed more problems earlier. And it could be that just people in certain areas getting very high doses or doing gardening and forestry and who are using the actual chemical are at more at risk. So, um, I think a pragmatic approach is there. We should be sort of lobbying to get rid of it when we can and and everywhere have choice. Um, washing the vegetables and then you've got this sort of dilemma about peeling or non-peeling. If you peel it, you lose all the nutrients and fibre. And if you leave leave it on, um, you know, you might be getting more pesticide. But speaking to the pesticide experts, they say that actually it goes beneath the skin anyway.
Dr Rupy: Oh, okay. Wow.
Tim Spector: So it doesn't totally protect you anyway. So, um, that's, uh, that, you know, you can't really win.
Dr Rupy: Yeah. I I know in the book you talked about some high profile cases where there've been some lawsuits that I believe are pending against some of the big agro-petrol, uh, agrochemical manufacturers, um, for people who have very very high levels of exposure. So, like you said, people who are working with the chemicals and farming, etc. Um, what do we know about the potential risks to the average consumer of conventional produce? And do you think it's alarming enough for us to at least try to go organic where possible, but not freak out about it? Um, or do you not think the data is clear at this point?
Tim Spector: Well, so there's two separate things. There are these anecdotes of people who have developed, uh, generally forms of non-Hodgkin's lymphoma, which is a rare, um, sort of leukemia type, um, uh, disease. And, uh, and they've been associated but not absolutely nailed to, uh, these people that used a lot of the sprays and several California courts, it's only in California that they award like 80 million dollar, um, payouts. Uh, and there is a class action for several billion pending in California. But each time it just goes to a higher court and so it might could take 10 years to resolve. Um, but when we people have looked and there isn't a sort of general massive increase in cancers, uh, in states that use a lot of the pesticides. So a lot of the epidemiology hasn't totally supported that. But there is a French study that did, uh, look at, uh, people over about 10 years who used a lot of organic foods and found they did have, uh, generally less less of these leukemias and lymphomas, um, suggesting that, you know, they were being relatively protected. Um, but again, it's an observational epidemiology study. So it's, uh, you know, the evidence is, I would say, weakly showing that there are has potential cancer effects. But I I would reassure people to say that these effects are likely to be small or rare, um, and otherwise we would have seen bigger signs in the data by now. Uh, but I think everything about it, when you look at the, you know, what it does to mice and what, you know, and the way the companies behaved in hiding the data, um, makes you suspect that, um, you know, you really don't want to be having it a lot regularly for 10, 20 years. So, so I have a pragmatic approach, but if someone offers me a nice looking carrot, I don't refuse it if it's, um, if it's not organic.
Dr Rupy: Yeah, yeah. Just give it a good wash, hey? Um, I wanted to ask, uh, just to end because I know we're we're limited on time here. Um, just a couple of practical suggestions, if you could sum up to the listeners of the key takeaway points that you want to, uh, bestow upon readers and and consumers of food, all of us across the the nation. What what what kind of practical tips would you give to, uh, to to people today to better look after their health going forward?
Tim Spector: I guess first, realise that we're all unique. And I think that's the sort of underlying message of the book really is that, um, if you realise that, you know, what works for someone else, what diet works for someone else, or what allergy or intolerance someone else has, doesn't mean you've got you've got the same one. So you've got to discover things for yourself, which means you need to experiment more. You know, we're all in ruts, partly from our culture, partly from our work, uh, and a lot from advertising and sort of brainwashing. Um, so try and get out of your rut, always have some different food. Um, as a general principle, while we're waiting for personalized nutrition to come in, and as I said, you know, we will have an app, uh, by Zoe in sometime in the new year in the UK, but it's going to be expensive, it's, you know, uh, it's going to be hard work to do. Until then, the best way of eating is to think for your what would your gut like to eat? What would your what do your microbes want for dinner? You know, that's if you think like that, you really can't go very far wrong. And that means having 30 different plants, uh, a week. So you're bringing in lots of diversity. And a plant can be a nut and a seed and a herb, you know, it's not not the the traditional our old-fashioned view of what a plant is. Um, and and if you do that, you can it doesn't really matter whether you have bits of meat or bits of fish or whatever. Um, avoid ultra-processed foods on a regular basis, but I'm not against anyone having the odd binge or treat. Um, avoid artificial sweeteners because, uh, they, uh, are really a fool's gold and they are not good for you. Um, I would, um, try and, um, ignore food labels. So I think that's one thing that we've really learned here is that, um, the label is there to make you buy it and ignore what else is on the packet. And so, look at them in a new light when you when you next go shopping. Uh, you know, and try and, um, buy things with fewer ingredients than and realise what ultra-processed food is. We all eat processed food all the time. It's this ultra-processed food at the other end of that spectrum that maybe plastered with healthy stickers like breakfast cereals, etc. Um, but I want people to also experiment with how they eat, not just what they eat. So I think there's this really big science now about, uh, time-restricted feeding and, uh, intermittent fasting and skipping breakfast or dinner, going down to two meal events a day rather than currently five or six, which is what the average Britain does. Uh, try these things out, see what really suits you. And I think you'll be pleasantly surprised about what you can do if you just take away some of this convention and everyone get out there and be their own citizen scientist.
Dr Rupy: Yeah, I I think those are amazing tips and I think we all need to run some more experiments. I've I've, uh, experimented myself with time-restricted feeding and doing gentle fasts. Like an example of what I do is if there's nothing in my fridge for breakfast, I just say to myself, well, I'll just wait until lunch and uh, I won't stress out about it. Um, so I think, you know, running these different, uh, unique sort of insights into how your body reacts and stuff is something we all need to be a little bit more comfortable with. And I think you mentioned it a couple of times now that the Zoe app and personalization, that for me is super exciting. Um, I know the Predict 2 study, I think, came out earlier this year in Nature. Um, and the premise of unique insights into how we should all be eating, I think is super exciting for nutritional science and that will revolutionize the field. If you could sort of look in in the future, in five years down the line, how do you think, uh, nutrition will evolve on a one-to-one basis and do you think it will be, uh, accessible to the average consumer?
Tim Spector: I see this as a bottom-up approach rather than a top-down. I can't see, uh, the government changing their relationship with the food industry. Um, obviously, most of us would have liked an extension of the sugar levy to junk foods and and making fruits and vegetables cheaper. But it's not going to happen with this government or probably the next. So I think, you know, we hopefully we'll see a groundswell of of movement that's going to really show the importance of food and trying to educate, get get food back on the the education agenda, you know, just as you've done for doctors, but, you know, it should be done at nursery school. Um, you know, kids should be playing with, you know, 20 different vegetables and, you know, rather than some plastic toys. Uh, so so that as a nation, you know, we come from this group of real food dummies, uh, compared to others, other countries. And we become really much more intelligent in knowing about the food. Uh, and in that way, we'll, you know, we will start to reject, uh, this cheap, uh, rubbish that we're being fed. And, you know, all be able to to cook a meal as we leave school. And I think that's that's really, that's really a crucial, uh, part of this and and realizing that, you know, a lot of these doctrines and and things like you're talking about the breakfast, you know, there's so much pressure on people say, you must eat breakfast. Uh, you know, if there's nothing in your fridge, you've got to go out and get something. You know, no, you don't. Um, I spent, you know, a week with the Hadza tribe in Tanzania, they don't even have a word for breakfast. You know, they don't have a fridge. So it didn't occur to them or all of our ancestors that we had to nip out to the nearest, you know, 7-Eleven to to get something to eat, otherwise we'd faint and fall over. You know, just I think it's really important that people realise that there there is just no such thing as, you know, really normal patterns of eating, but let's eat less, you know, let's enjoy it more and, you know, uh, eat more intelligently. I think that's that's really important. And find the best time to eat for you. I did this test in in the Predict and it turned out that I metabolize my muffins, um, better in the evening than in the morning, which is unlike most people, whereas, so most people it's the other way around, but again, one in four people are going to be the opposite and you won't know until you start experimenting. Um, and so it suits me, you know, like you a couple of times a week to to skip breakfast, although I enjoy breakfast. So, you know,
Dr Rupy: Yeah, yeah, me too. I love my breakfast.
Tim Spector: But it's, you know, yes, if you don't have the an option of a delicious one, it's nice to, you know, just go without rather than having one just because you feel guilty because your mother told you to have breakfast. You know, that that's that's where I think we need to change people's mentality and um, and just get everyone, you know, much more intelligent about knowing about food, where it comes from, all the all the tricks and cons, you know, particularly, you know, and there isn't one right way to do everything. It's, um, you know, labeling people as vegans or vegetarians or, uh, gluten-frees or, you know, fasters or non-fasters, you know, we should be able to change religions every day. Feel comfortable about it and not feel guilty, you know, to to change our minds and have to stick to things. I think that's that's really important. So being flexible in what you're eating is is also, but, you know, the point of eating is also to be, you know, is to enjoy it. And I think we mustn't, uh, lose sight of that and get too obsessed. Uh, and so I hope I haven't put anyone off eating. And they'll enjoy food even more with plenty of, uh, good salt and fat in it if it tastes good.
Dr Rupy: Yeah. No, I'm I'm sure you haven't put anyone off, especially me. I'm thinking about my lunch now. Um, Tim, that that was brilliant. I mean, I could have talked to you about a whole bunch of other things like, you know, mood and food and, um, breakfast in a bit more detail, but I think, you know, those are some amazing salient points from from the book and
Tim Spector: We can always chat again.
Dr Rupy: Absolutely. Yeah, I'd love to. I'd love to, Tim. And then hopefully I can actually cook for you as well, um, which I'd love to do at some point in the future.
Tim Spector: Look forward to it.
Dr Rupy: I really enjoyed this podcast episode with Professor Tim. I hope you enjoyed it too. Just to give you a summary as to what we talked about with regards to food and how to lead a healthier, more informed life. Recognise that we are all unique. Yes, there are a few things that will definitely be pretty much universal across the board. That is largely plants, largely whole foods, making sure that you're getting good quality fats, eating plenty of different types of fibre and diversity. Some of the principles that map perfectly onto what we do in the Doctor's Kitchen and all the books that I've written. Run experiments. Like I said, I've experimented with doing gentle fasting. I tend to eat in a 10 to 11 hour window. Again, both of which I've talked about in both of my books. Be aware and be skeptical of product labels and that includes one that are actually generated by the government guidelines as well. Again, controversial subject. I think they can create a lot more confusion than clarity. There are lots of reasons why you should be having at least 30 different plants a week. And I think one of the things that I want to pick up on there that Professor Tim mentioned was nuts, seeds and herbs are also included in that differential of different plants that we should be consuming. Something that's very important and something that gets overlooked by just the focus on fruit and veggies alone. Avoid ultra-processed foods. It goes without saying if you're an avid listener to the Doctor's Kitchen, please do avoid them. That isn't to say that you should never have them, but they should not be a staple in your diet. And artificially sweet sweetened beverages, things like the diet drinks or the low calorie versions of said drinks. They are fool's gold to quote Professor Tim himself. And I agree, looking at the research, you know, there is a lot that we don't know and I think I take a pragmatic principle as does Professor Tim in that we should be avoiding them until they're proven to be safe. I really hope you enjoyed this podcast episode. Please do give us a five-star review if you enjoyed it. Share it with your family members if they feel that they need to listen to this information and I will catch you here next week.
