Why Diets Always Fail: Harvard Professor Exposes Food Myths | Daniel Lieberman (E439)

0:04Every serving of meat increases your risk of dying in a given year by I think 13%. What? There's no such thing as an optimal diet. There's no magic bullet diet. There's no diet that solves every problem. When you diet, which is to basically eat fewer calories than you're spending, what happens? We get hungry. Food companies are making a fortune. They add all these additives, so you combine all these products. You have foods that we love, that we crave, and the manufacturers know exactly what they're doing, we're victims, right? I mean, there's so much prepared food and it's so cheap. All you need to know is how to press a button.

0:35I think the best diets aren't actually diets. Explain that.

0:43Daniel, welcome back to High Performance. Thank you. I'm delighted to be here. So how would you answer that first question? What if the problem isn't that we don't know enough about diets, but we've misunderstood what humans were actually designed to eat? Well, I mean, I think you hit the nail on the head. I mean, we evolved to get our food, right? I mean, if you're a hunter-gatherer or a farmer, you spend your life working to get your food and to grow your food. And all of a sudden, we're in this really weird environment where you walk into a supermarket and there's 30 ,000, 40 ,000 different kinds of food.

1:15And now we have to choose our food. And we never evolved to do that. And then we get sick from the food that we eat. And now we have to lose weight. And we never evolved to lose weight either. And so we're now asking people to do things that we were never evolved to do. And then we blame them and shame them for making the wrong choice or being confused, as if there's something wrong with them. So I think, you know, an evolutionary perspective can help all of us sort of think better about food and diet and health and how to be kind of nicer to each other. I really want to dive straight in with a question that is very interesting.

1:54You've just said, and I've never heard anyone else say it on our show before, including I think when we spoke last time, maybe you did, but you said we never evolved to diet. Yeah. So I feel like, I mean, I'm 47. Damien is 51. You're youngins. True, but we are both in a sea of middle-aged men trying to diet the weight off us, feeling like we're failures wondering like we are struggling and then you see them and say well evolutionarily we weren't even designed to go on to diets to lose weight so we're trying to force our bodies to do something that they were never designed to do in the first place?

2:33Correct, when you diet, right, which is to basically eat less than your fewer calories than you're spending what happens? We get hungry, right? And hunger is one of the most fundamental adaptations to prevent us to lose weight When you're losing weight, your body mounts a whole suite of responses. These are deep-seated, profound adaptations to prevent us from losing weight. So your fat cells, for example, produce a hormone called leptin. And when you decrease the amount of fat in your body, your leptin levels drop. Your hypothalamus in your brain says, uh-oh, you're losing fat, and it makes you hungry.

3:12When your stomach is empty, your stomach produces a hormone called ghrelin that makes you hungry. and your intestine doesn't have food. It produces neurotransmitters that send signals to your brain to tell you to eat. No wonder we're failing. Because we never evolved to do this because we lived in environments for millions of years where people struggled to get enough food and body fat plays an incredibly important role in our evolutionary biology. Humans are unusually fat creatures. So we evolved to have a lot of fat and to store a lot of fat, but we never evolved to have the abundance that we have today.

3:46And so what happens is that we have this kind of mismatch, right? We end up, you know, we walk into the supermarket, we make the wrong choices or we just, you know, or whatever. And then we get blamed for them and shamed for them. And then when we try to lose the weight, which is really hard to do, we then were made to feel that something's wrong with us and we're inadequate. It's really, truly, and it's depressingly hard to lose weight. And so I think we need to be compassionate and we need to help people understand that it's not their fault and give them the information that they need to help them, A, prevent weight gain in the first place, help them understand what's going on with their bodies, and also help them overcome some of these adaptations so that they can do a better job, which is never going to be easy.

4:28And we should stop lying to each other. Think of all the diets out there that claim to be easy, the miracle cure, seven weeks to do this, et cetera, et cetera. I mean, that's how you make money, right? And most of these diets fail. And I think we need to start having to be honest to each other. and that partly means explaining why it's so hard. What do we say to those people then if we're telling them that dieting is hard and you're not designed evolutionarily to do it? What's the first thing we should tell them about how they can? Well, I mean, first of all, you can lose weight and people do, right?

4:58There are study after study after study shows that people can and do lose weight. So one important distinction is that when you're reading diet information, to make a distinction between efficacy and effectiveness. So efficacy in the medical world is how well something works under ideal conditions. So if I locked you in a room and gave you a special diet and you couldn't go out and get, you know, whatever your secret passion is, I don't know, sausage rolls. I have no idea what it is. How do you know me so well, so great? We've only met once before. Back in the time, I used to love sausage rolls too, but now I want to let myself eat them.

5:36But anyway, Okay.

5:40Lock you in a room so you can't get those sorts of foods. And so you have no choice. And to eat the diet I give to you, you will lose weight. In fact, almost any non, pardon the expression, crap diet will help people lose weight. You can go on a low-fat diet, a low-carb diet, a low-calorie diet, et cetera. All of these will work. But the problem is that in the real world, intervenes. So you try the diet, you lose some weight, then you go to a New Year's Eve party, and bam, you know, or whatever. We all know what happens. Life gets in the way or you're stressed, you're tired, you come home, you don't have a lot of time to cook.

6:15So you get the frozen pizza or whatever. There are so many things that happen because of our world. And also there are a lot of companies out there who know exactly how our brains work. They're manufacturing foods that appeal to us. They're convenient, they're cheap, they're tasty. They click all the boxes. and it's hard for us to overcome that. So you can diet. There are diets that have high efficacy. The problem is that in the real world, that turns into low effectiveness. But knowledge, whoops, Sergeant, knowledge can help us, right? Learning that can help us understand our symptoms, understand what's going on and help us turn that low effectiveness into high efficacy.

7:01So knowledge is power. Brilliant. so we want to explore that knowledge and how we get into it and i think one of the first things when i read your brilliant book was the conditioning long before we even start to consciously acquire this knowledge you talk about the role of your mum that you like when you were writing the book is there's a moving passage where you write about she passed away in the course of your research for this but you talk about the influence that she's had in terms of your relationship with food. Yeah. I mean, all of us, all of us, you know, I mean, food is about more than just health, right?

7:39It's about family. It's about culture. It's about enjoyment, you know? I mean, food is so important to being human, right? And sharing food and think about the diversity of food. And so we all have our own food stories, right? And in my case, my mother was, my brother and I called her the food police. She, during the kind of low-fat craze of the 70s, she bought into it lock, stock, and barrel, right? In our house, you know, eggs were banned. They were like poison pills, right? You know, there was no butter. There was, you know, we had to have low-fat milk. She would buy, it was disgusting. It was this powdered low-fat milk.

8:15My brother and I hated it, right? You know, but she was trying her best, right? She was trying to feed us healthy food. And fortunately, she didn't buy a lot of junk food either. So we probably had a reasonably healthy diet. But in a way, her low-fat diet really didn't help her in the end. So she was underweight. And as she got older, that really had serious negative consequences. She started falling a lot. She had no fat on her body, so there was nothing to cushion her falls. She was losing muscle mass because she just didn't have enough energy, right? So she was not getting enough protein either.

8:50And I would beg her, you know, please, you know, I'd bring her chocolates. I'd try to get her to eat cheese, and she'd just eat a little bit. She just couldn't overcome. Because she, you know, I think we all, diet is very tribal. People have certain diets that they like, and some people like the carnivore diet. Some people like the low-fat diet, vegan. I mean, there's so many diets, and people come to identify that diet, and she couldn't change her habits. and it made me think about how it's hard to figure out what diet to eat because, you know, the problem is that when we eat something, like the lunch I had today, if I had that lunch over and over and again for thousands and thousands of meals, it would take a long time for that to have effect on my health.

9:37You know, it doesn't take one meal. I mean, of course, if it made me sick, you know, I'd figure it out immediately. But in terms of its effect on my heart disease or or diabetes or cancer. How would you figure that out? You can't. We need science, right? We need high-quality, long-term perspective studies combined with mechanistic studies rather than our own gut instinct or tribal instincts. And I think so many of us pick a diet, it becomes like because of our friends, because of our mothers, because of our online community, et cetera. But those might not be the best diets for us. and yet we engage in confirmation bias.

10:16You know, that's the diet for me, right? And people will do pseudoscience. We'll pick the studies that support our diet and ignore the ones that don't. And you know what? By the time it's consequential, it's too late. As Damien mentioned a moment ago, you lost your mom while you were doing your research for this book. I'm sorry for your loss because I think people often think when you lose a parent when you're older, you recover quickly. And anyone that's lost a parent knows that that's absolutely not the experience, is it? You feel like a five-year-old kid when none of your parents passes away.

10:47Every time I come back from a trip, I used to call my mother and I got home and I was just about to dial and I realized, oh, I can't call her. It's very strange, yeah. So the woman that called eggs giant poison pills, what would she think of your new book, Fed Up? What would she make of this, do you think? Oh, well, she was always very proud. so she would have probably argued with me a little bit about the fat, right? Because I point out that saturated fat is probably not as bad as she thought.

11:22But, you know, my father was a scientist, so she was very pro-science. But there's a lovely line that you attribute to your mom where you write, she was not entirely correct about what foods made you fat, but she was right to worry about obesity. how do we tell the difference well I mean she she was worried about fat because she believed she bought into this idea that fat makes you fat and so even avocados I love avocados she never bought avocados because they were very fatty but of course they're healthy fats avocados but she did know that McDonald's isn't good for you so we never got to go to McDonald's I was jealous of my friends who got to go to these very exciting restaurants I was never allowed to go to unless I was with my friends.

12:14She never bought cookies or those sugary cereals and stuff. So my mother made a lot of really good choices. So, I mean, her problems were different from most people's problems. I mean, most people, their problem is they've got too much weight, not enough. so but but but she again i think to me she's just an evidence of how we cling to our ideas and and and and also there are trade-offs i mean everything everything has trade-offs and and a low-fat diet can be beneficial in some ways but it has other trade-offs um it can be harmful in other ways everything has trade-offs and that's one of the arguments of the book so that you know when people say this diet is optimal this is this food is perfect it's salesmanship it's not how the world works.

12:57What have you learned about our ability to not be so tribal and not be so emotional about our decision-making to be able to change our mind when the evidence changes, our mind changes? Well, that's, I think, really hard. I mean, I think we're not evolved to do that. But the thing is that most people from most of human evolutionary history, they didn't choose their food, right? You ate what your culture had. If you were, you know, if you've grown up in the Mediterranean and the, you know, 500 years ago, you'd eat a Mediterranean diet because what else were you going to eat, right? If you were growing up in England 300 years ago, you'd be drinking ale and having, you know, whole grain bread and cheese and, you know, potatoes.

13:39Well, not potatoes because until they were imported from South America, but whatever. You'd be eating turnips, right? And I mean, that's what you'd eat because you didn't have any other choice, right? And now you walk into the supermarket and it's astonishing. I mean, you can eat anything, any time of the year. There's all this stuff and over 50 % of it's ultra processed and you go into a restaurant and I mean, I can decide if I want to have Chinese food tonight, Indian food or French food or this food or that food and you go to a menu and there's all these different options. We never evolved to do that.

14:10And so then we come up with our own, and then we're often not taught the science necessary to evaluate it, or we're not taught the ways of thinking to evaluate the science, because there's a lot of bad information out there. You pick up the newspaper, and one day you read that fat is bad for you, and the next day you read, actually, yeah, it's not so bad for you. Go ahead, eat as much butter as you want, and you read that mushrooms will kill you, and the next day you read, mushrooms are going to prevent cancer, and we're getting whiplashed constantly, and how do we evaluate this confusing information?

14:48We're not taught these skills and it's hard. We'll be right back after a quick word from our partners.

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17:05Get ahead of the curve with an LA28 hospitality package. Discover more at hospitality.la28.org forward slash high performance. So can you give us some insight into how you think about it to be able to make better choices? Because that sense of overwhelm is very real for many of us. Yeah. Well, I mean, I don't think there's a simple... I mean, that's why I wrote the book. I mean, literally, the goal in that book was to, A, help people realize that there's nothing wrong with them and they shouldn't feel bad about themselves. But B, I tried to put in that book, and tried to make it fun and interesting and all that, the information I think everybody needs to know, not only about the effect of fat and unsaturated fats versus saturated fats and fiber and this, that, and the other, but also I tried to put in the book a lot of information about how to evaluate the evidence, how to read a meta-analysis versus a single study, how to put together information on mechanism plus epidemiological sort of big-scale studies so that all of us can make our own decisions because there is no one perfect diet.

18:14And what you care about might not be what I care about. Maybe I'm more worried about Alzheimer's and you're worried about, I don't know, cancer. I'm just making it up. But we're all different, right? And I think we all have to figure it out for ourselves. and the problem is that we're not taught that. I mean, even doctors aren't taught that. You go to medical school and you get almost no nutrition. That's insane if you think about it, right? I mean, doctors are trained to treat people after they get sick, not prevent them from getting sick in the first place. We have a system that really doesn't help us.

18:53So I think that's what I tried to do. I tried to give people information. and you know if you want to eat everybody should eat what they want but at least they should have the information so they can make their own decisions rationally with the let's figure out what's best for them i don't know if it's the same in north america but over here in the uk we've pretty much stopped teaching people how to cook at school yeah is it the same yeah yeah i mean nobody gets stuck that and that was my mom's job she was a what we call in those as home economics teacher, which then became a food technology teacher.

19:24Right. Yeah, no, I remember when I was a kid, we had that. Then it stopped. Yeah. Fortunately, my parents made me cook a lot when I was a kid. I had no choice in it. So I like to cook, but it's true. People don't learn to cook. And also, you don't need to anymore, right? I mean, there's so much prepared food, and it's so cheap. All you need to know is how to press a button, right? And food companies are making a fortune off of it. But often the foods that are prepared that only require pressing a button are not necessarily good for us. In fact, many of them are really bad for us. There's an interesting concept here.

20:01I interviewed someone not long ago who is the CEO of one of the biggest fast food chains in the UK. And off camera I said, how do you feel about the fact that you are selling stuff which we know isn't great for people? And they said it's supply and demand. Like this is what people want. We're merely providing the demand. you know you spoke about you wouldn't go to mcdonald's as a kid my mum was very similar as a home economist and i would longingly look at the other children that were getting cheeseburgers and chips on a saturday and i was eating a you know alfalfa salad or something so how we reach this point because big business has made us think that this is how we should eat and this is what we should eat or how we reach this point because human beings have this natural propensity for fat and salt and sugar and flavor and deliciousness.

20:51It's both. It's both. Both statements are correct. I mean, we love foods that are filled with fat, sugar, and salt, right? Why? Because they're full of energy. I mean, can you name, I love to ask people this, the one natural food that has a lot of fat and sugar in it, the natural food that you can't buy?

21:15Banana. It was your mother's milk. milk. Milk is the only natural food that's rich in both fat and sugar. It also has some salt in it, too. And we love foods that have a lot of fat and a lot of sugar in them, but they're really rare in nature. So when we eat doughnuts, cake, whatever, we're basically going back to our infancy, right? And think about it this way. If you take a food and you put way too much fat in it, right? Just like eat a stick of butter. It's disgusting, right? Or take a food and just make it pure sugar. It's cloying. It's too much. Take a lot of fat, a lot of sugar. You combine the two together.

21:49It hits what we call our bliss point. And you add a lot of salt even more. And so the fast food companies, they know this. They're engineering food that light up our brains. They know exactly what they're doing. Plus, they remove the fiber, which is really healthy for us because the fiber adds bulk and it goes rancid and it's not good for storage and, you know, et cetera. And so they create these foods. And then, of course, they add all these preservatives and stuff like that. So if you have a lot of fat and sugar, fat in a food, you need to have these emulsifiers to prevent the sats from separating.

22:21Otherwise, it would be disgusting, right? But these emulsifiers eat away the lining of our gut. So they add all these additives. So you combine all these products. You have foods that we love, that we crave, so that we buy them. Because, you know, I like donuts as much as anybody else, right? And the manufacturers know exactly what they're doing. We're victims, right? So I talk about mismatches and hypermatches. Mismatches are conditions that we get because our bodies are not well adapted for the novel environmental conditions. We're not adapted to eating a lot of sugar. We're not adapted to eating massive amounts of fat.

22:56We're not adapted to eating all these calories, and that gives us diabetes and heart disease and cancer and blah, blah, blah, blah. But we are hypermatched. These foods are hypermatched to us because they give us what we really want. So we have this combination of hypermatched foods and mismatched conditions, and we're now kind of stuck in the middle. And solving this problem is going to be a real challenge because, look, I like these foods as much as anybody else. And when I walk by, you know, when I go to a restaurant and there's fish and chips, I mean, yeah, I love fish and chips as much as anybody else, right?

23:35And I have to, and I eat them, you know, just like everybody else, but I have to overcome, I have to tell my slow brain to overcome my fast brain, my instincts, to try to help me not do that. And that's hard. And plus, healthy foods are often more expensive than inexpensive foods. And they're more time-consuming to cook your own food. And so if you're stressed, you have a lot of kids, you have commuting, et cetera, et cetera, I mean, there's a confluence of problems. It's not an easy problem. I'm not pretending there's an easy answer. There isn't an easy answer. So let me ask you this then with total honesty, which is what you always offer.

24:14Do you believe it is solvable? I think so. But it's going to take a group effort, right? I think it's going to require on the part of individuals education and information, not just about how to evaluate the nutrition facts labels and all that kind of stuff, but also I think helping people understand what we were just talking about earlier, that it's not their fault, right? There's nothing wrong with them. People are made to feel bad and they're made to feel ashamed or inadequate or there's something wrong with them. I think we help people understand that they're fighting aspects of our biology that they can't control.

24:51At the same time, I think it's a kind of a collective social political problem, right? I mean, look, we can't get away from processed food. We have 8 billion people on the planet. We can't all go and eat grass-fed beef and grow vegetables in our garden and that kind of stuff. We're going to have to rely on processed food. But processed food doesn't have to be bad for you. There are all kinds of processed foods that are perfectly healthy. Why can't we get more of them? So, for example, here in the UK, you have those on food labels in some foods. I think it's optional, right? There's the green, amber, and red.

25:31Yeah, the travel light system. And, you know, I mean, you could argue about whether they're getting it quite right and, you know, et cetera. But that's a start, right? Why not make that more common? Or like when you buy a package of cigarettes here, right? It has like a skull and crossbones on it and it's, you know, it says, this will kill you, right? Yeah. Well, you know, the junk food that they sell in the supermarket will also kill you. Like a cigarette, slowly, gradually, you know, pizza by pizza, slowly, slowly, slowly. Some countries do have a warning label on junk food. Yeah, but not like a skull and crossbones.

26:03I mean, you know. Well, we interviewed Chris Van Tulekin, who wrote the book, Ultra Processed Food. Yeah, great book. He told us about Mexico because it was very distinct before and after because of a trade embargo. So, diabetes only started to increase significantly when the embargo was lifted. That's correct. American Foods could come in. And he was now saying there was a law passed where they had the equivalent of the skull and crossbones on high sugar food. Yeah. And, you know, I mean, is this the only solution? No. But there's not going to be one single magic bullet solution to this problem.

26:43It's a collective problem that's going to require everything from educating doctors, educating the public, giving people information, but also, you know, taxing certain kinds of foods maybe, more kinds of aggressive labels, giving people information, but also changes in the policies that make these foods so, you know, the tax breaks that these companies get. I mean, I'm not a politician, right? So I don't know all the solutions. But look, if we can put people on the moon, if we can fight cancer, if we can, you know, as a species, we're capable of all kinds of amazing things. Nobody disputes that right now we are suffering from a wide range of chronic diseases that are mismatches that we don't have to get, that we shouldn't be getting, that nobody really wants.

27:35And it's a solvable problem, but we just need to have the collective action and the wisdom to try to solve it. And right now, I don't think the will is there. I think that people recognize the issue in the UK and the United States and other places but are we, you know, and there are movements to try to do that but right now it's really more on individuals. It's not a societal solution yet. Yes. Can I ask you a question prompted by that conversation with Chris that's come to mind that have you received pushback from the food industry to what you've done? because he told us some examples of where he'd been invited by some fast food companies to come and speak to their senior management and somewhere in the small print of the contract was that you can never speak ill of them again for the fee that they were paying.

28:28Have you had your own experience of seeing what he called the Spawn? The book was only just published, so I haven't had that yet and they're probably kind of scared of me. Get ready. I mean, I do get lots of emails from people about their diets. I've gotten angry emails from vegans, from carnivore dieters, et cetera, more from individuals than from corporations. But I stay away from companies for the most part. So can we talk about the experiment you did? Sure. Would you tell us a little bit about it? So in the book, we tell the history of diet. I tell the history of diet. I start with our divergence from chimpanzees.

29:05So the first half of the book tells the history of food up to the industrial era. and then the second half of the book is about food in today and so what i decided to do is to pair a diet with each chapter of the book um that kind of told that went along with the story so we started off with and my wife decided to join me or had the my wife is very funny so it was great to have her how did that conversation go about deciding did you ask her or did she volunteer oh i probably over a series of conversations but you know we we spent a lot of time together so So I don't remember one particular conversation, but she was game.

29:41She loved the idea. She may even propose it, I think, actually. Anyway, so we started off with a raw food diet because we started off before cooking. And then we did the paleo diet and we did various other diets. And she joined me for most of them, though there was one diet. She said, I tried eating a meal replacement, like soil interhuel. And she said, over my dead body, will I do this with you? Really? Why was she so anti that? Because it's disgusting, you know, not eating food for several weeks. And how was it? It was awful. I mean, have you ever tried one of these meal replacement things? It's like a really gloppy milkshake, right?

30:21If you're having like one, okay, not too bad. Although I kind of worry what's in it, right? And I decided to do it just for lunch and breakfast. I decided that I could not do that all day long. But I have to tell you, after about a few days, I came to really fear my meals because like, like, shall I have strawberry or chocolate or vanilla? I mean, there are only a few flavors and they're all disgusting actually after a while. And how did they make you feel? They didn't actually make me sick. I mean, they were okay, but there's something unsatisfying about them because you're not chewing, right?

30:56And there's, there's just like this, I mean, I got all the nutrients I needed and I could make it to the next meal, but it was unsatisfying. I mean, it was just a stunt, to be honest. So it wasn't, of various diets, was probably the least serious of the diets. You did the raw food diet as well. That was by far the worst, yeah. Yeah, no question about it. Would you talk us through what a day's food would look like for you and the impact of it? Because I still see people peddling this raw food diet as the future of mankind and the fact that this is where we should all be going because it's pure and clean and we'll live forever or whatever.

31:33Yeah, that's the naturalistic fallacy, right? That's the idea that if you go back to nature, and it's true, other animals. So the idea behind raw food diets started back in the beginning of the Industrial Revolution when people were beginning to get diabetes and obesity-related diseases, et cetera. And this guy Maximilian Berkher-Brenner in Zurich said, well, you know, the cows out there, they're not getting these diseases and the sheep aren't getting these diseases and other animals don't get these diseases. It must be because when we cook our food, we're losing all the nutrients, we're getting sick.

32:04That was the idea. So it's more natural not to cook your food, which is true. It is more natural not to cook your food. And so that's the beginning of the raw food movement, and they still believe this. But here's the thing. We evolved to cook our food, right? And in human evolution, cooking started sometime in the last one to two million years. By 400 ,000 years ago, everybody cooked a lot of their food. It became really important, so much so that we are now actually biologically adapted to eating cooked food. Our small intestines shrank. Right. Our teeth are smaller. I mean, we don't have the adaptation.

32:39You could not eat a raw food diet if you were a hunter-gatherer. You'd die. There's no possibility. Why would you die? Because the food quality is not... Because the raw foodists today, they're going to the fanciest food stores and they're buying high quality fruits and vegetables and they're shipped around the world, et cetera. And even then they're struggling to get enough energy because when you cook your food, you actually get more nutrients, not less nutrients from your food, because you break down cell walls, you spend less energy digesting your food. On the raw food diet, I can tell you, we were going to the fanciest store in Cambridge, Massachusetts, you know, it's called Whole Foods, we could get, you know, super high quality foods, and I just couldn't get enough food.

33:20I mean, I was just constantly hungry. And we were like, I was eating muesli for breakfast, which, by the way, is invented by Dr. Berger Brenner. And I was making smoothies, and I was having salads, and, you know, we were, having zucchini noodles, zoodles, you know, and, and, you know, we were trying, I mean, it's a huge amount of work. Nothing was cooked. Nothing, zilch. And it was, except, except, except I did, I did make an exception for coffee. I'm not living without coffee. Lord on Daniel. Sorry. I snuck down to the basement and I, and I cheated on coffee. And I think I might've had a few glasses of wine and most wine is pasteurized thanks to Louis Pasteur so that it doesn't go bad.

34:01And so that's probably a violation of the raw food diet. But other than that, and it was just awful. So after three days, my wife quit because she was depressed. And, you know, I don't... That's so interesting. I think it's partly because of energy, but also, you know, our guts produce dopamine and serotonin. And actually the most, we produce more of it in our guts than anywhere else and it affects our brains. And I think she was not getting enough dopamine and serotonin. And I think that was why she... I mean, I can't prove that. And then one morning, I came back, and she was kind of smiling, and she looked so much happier.

34:36And she confessed that she snuck out and had a bagel. And I made it only a day after that. And how many days did you manage in total? Four. Four, yeah, and that was it. But, I mean, I think it's interesting for people to understand physically how different it made you feel. So they also think mentally, like, let's understand our mental health is impacted by the food that we eat. Yeah, and I spent all my time thinking about what I was going to eat. I mean, when I was on this raw food, it was really just a chore. And I'll tell you a funny story. So I once went to the supermarket in Cambridge. This is a very, very fancy supermarket.

35:08They sell all these wonderful fresh vegetables, et cetera. It's a place where a lot of well-off people go to get. And there was a woman in front of me, and she had a sopping cart just filled with gorgeous vegetables. And this is before I wrote the book. And we were just standing in line waiting to buy food. And I said to her, oh, are you? And she's really thin. And I said, by chance, are you a raw foodist? And she snapped at me. Yes, I am. Why?

35:37And I now think I can put the two together. She's not getting enough energy, so she's kind of hangry. And maybe, you know, she's not getting enough dopamine and serotonin. I don't know. But I don't think it was doing her a lot of good. She needed a burger. Exactly. But to take you back to an earlier answer, Daniel, You use the word, I cheated. I cheated, I had a coffee. I cheated, I had some wine. And even that language then implies, it goes back to this idea of failure. It's something that we should be ashamed of. I went down to the basement to do it. You know, or Tonya, your wife saying, oh, I sneaked out and had a bagel.

36:13The language that we use around this, when we talk about restriction, is psychologically quite confining for us. Dead on, dead on. I mean, look, so many diets are based on elimination. You can't do this. You can't do that. You can't do this. Forbidden, prohibited. You can't have more than 60 grams of carbohydrate. You can't have anything with added sugar. You can't have this. Elimination is very common to diets. And I love that expression attributed to Epicurus. Practice moderation so you can enjoy the pleasures of life in abundance. I think the best diets are not elimination diets. they're sensible diets I mean I would hate to never live my life and never have anything sweet you know never have a dessert rather than eliminate them why not just not have them very often right I don't think we need to practice elimination but I think there's this and so many of these diets are based on just like certain you know almost like cults you were going to say religions Yeah, religions are cults that are based on prohibitions.

37:22There's a sin involved, right? And it makes people feel bad. And again, you're also having to overcome. I mean, who doesn't want a bagel every once in a while or something like that? Yeah, yeah. And that's, again, why there's a distinction between efficacy and effectiveness. Elimination is rarely effective. It could have high efficacy, but it's rarely effective, at least for most normal human beings. Can we talk about the concept that you write about, the hedgehog and the fox? Yeah. I think this is interesting for people and can really help them kind of process what we're talking about on this podcast.

38:00Yeah, so this is really kind of the framing of the book. So I start out with two points. First is that we never evolved to ask the question, what should I eat? You know, you just eat what you have for most of human history. There are no supermarkets, right? But then the second thing is when you're trying to decide what should I eat, there are two kind of opposite ways of thinking about it. And the metaphor I use is from a fragment of poetry from 7th century BC by a guy named Archilogus of Paris. And he wrote, the fox knows many things, but the hedgehog knows one big thing. And what we think he meant, because it's only a fragment from a few thousand years ago, is that when you chase a fox, it'll do anything to escape.

38:42It's wily, it'll hide, it'll run fast, it'll whatever. ever. Whereas when a hedgehog, when you chase a hedgehog, what does it do? It rolls into a ball. That's the only thing it knows how to do. And so there's a famous essay by a philosopher named Isaiah Berlin, but he divides the world into hedgehogs and foxes. But foxes see nuance. They see trade-offs. They see complexity. They see that there's more than one solution to things. Whereas hedgehogs always have like a single idea, big idea, magic bullet solution. And I think The problem with the way in which we often think about diet is that we go for hedgehog diets.

39:21Don't cook your food. Don't ever eat this. Don't ever eat that. Never eat plants. Never eat animals. Never eat anything from the deadly nightshade family. Never eat UPFs even. Those are, I think, hedgehog diets. And that's not how things work. First of all, we're all different. You and I are all different. We're a different age. We have different genetics. We have come from different backgrounds. Some of us might be more worried about Alzheimer's versus heart disease versus cancer versus this versus that. We have different goals. We have different incomes. We have different, you know, whatever.

40:00So coming up with one single solution to diet just doesn't work. That's why the one word I came to really hate as I was working on this book is the word optimal. If somebody tells you a diet is optimal, To me, that's a red flag that they're overselling a diet. There's no such thing as an optimal diet. There's no magic bullet diet. There's no diet that solves every problem. All diets have trade-offs. All foods have trade-offs. And we need to accept that. That's just how the world works. We need to be foxes, not hedgehogs. And when we're foxes, we can relax a little bit. We can see a little bit of the complexity and pick a diet that works for us without going crazy.

40:40and that's why I think the best diets aren't actually diets, they're cuisines. Explain that. So think about the Mediterranean diet with a capital D, right? I mean, it's a lot of olive oil, you're supposed to have a lot of whole grain foods and not too much meat, et cetera, et cetera. But it's really based on a cuisine, right? What you'd eat, I mean, not necessarily in a fancy restaurant in Rome, which is going to be mostly pasta, right, or whatever, but you know what people actually eat around the dinner table most days of the week and or at least did before before upfs invaded is italy as well as they as they did here and you know i mean it's not a perfect diet but but it works really well i mean there are study after i mean if you want one diet that has scientific evidence behind it hands down the mediterranean diet wins with no question right there are there are now dozens of prospective randomized controlled studies where they've actually, like there's one in Spain where they put 7 ,000 Spanish people and that half of them were randomized to a Mediterranean diet and half were eating a, I guess, a non-Mediterranean diet.

41:44And some of the people on the Mediterranean diet were eating extra olive oil and some were eating extra walnuts. And, you know, they stopped the experiment after five years because the people on the non-Mediterranean diet were dying so much faster that there was not ethical to continue the experiment. Oh my days. Yeah. Because it was, not that the Mediterranean diet was the problem, was the non-Mediterranean controlled diet. You were kidding those people. Yeah, they were just like dying like flies. I'm being a little bit exaggerating. But that's just one of many studies. I mean, we have study after study after study showing that if you were going to pick from scientific basis a diet that has the most likelihood to prevent you from being obese, prevent you from getting cancer, prevent you from getting heart disease, etc., you'd pick the Mediterranean diet.

42:28Now, there's a little bit of Eurocentrism there because Europeans and Americans tend to study European kind of diets more. So I'd make a bet that a traditional Asian diet would be just as good, a traditional Mesoamerican diet, et cetera. There's just not enough studies of those diets. But that's what you'd pick if you had no information available to you other than just high-quality science, and that's what you'd pick. We had Professor Brian Cox on here a few years ago who his single piece of advice was to think like a scientist. Yeah. Which was to hold your beliefs lightly when the information changes.

43:02you change your position. I'm interested if you could tell us a little bit about, I mean, it sounds like you're echoing the same point. How do we all think like scientists to be able to make better choices then? Be skeptical and be a fox. I mean, scientists, hedgehogs rarely succeed in science, right? If you have one, occasionally you can get right. If you have one big idea, sometimes you're right, but usually you're wrong, right? Science is about being wrong, right science is just a process um there's no one answer right so and so so when like when i read a scientific paper and i pick it up and i teach my students this right i don't think gee what am i gonna learn from this paper when i pick up the paper i think what's wrong with this paper like what are the assumptions that are what's the you know i try to i try to find the issues the faults whatever and i'm not like a jackass about it i'm not trying to you know go after it but i'm i read it with a dose of skepticism.

43:59So when I read a particular study in the newspaper about, you know, the latest study that came out about, I don't know, bananas, right? I think, okay, well, what could be wrong with this study? And so instead of relying on one study, what I do is I go for meta-analyses. I go for, and what's wonderful, it's not all this stuff is available to us now for free. You can get online, you can get on PubMed, for example, or whatever, and you can actually type in and you can actually restrict it. This is free to the entire world and restrict your analysis. And you can look up banana and health, put word banana health, and then click the box, meta-analysis, and you'll get papers which summarize all 20 studies that gave people bananas.

44:42I'm just making up bananas here. And find out what the balance of the evidence is, because one study ain't going to do it, right? Because it could be that that study was on, five-year-olds from Jamaica as opposed to the next study was on 80-year-olds from Tokyo or whatever, I don't know, or people who had diabetes, whatever. You want to know the balance of the evidence and a thoughtful analysis that looks at who the population was, how long the study was, how well did they correct for the fact that people were smoking or not smoking, et cetera, et cetera. So those kinds of studies help us. And the other thing you want to look for is mechanism, right?

45:18So in addition to having large-scale data that's prospective and high quality, you also want to know that there's some mechanism behind it. There's just some association between – like there was just a study out that was published. I think it came out today in the British Medical Journal about steps. And they looked at people's step counts and also step rate. And they showed that people who had higher step rates and had more steps did better in terms of dying. Right. And so the question, I read the paper, and of course it's a nice study, but is the higher step rate important? Was that the reason that they didn't die, or is it because people who are healthier are fitter, so they're actually just walking faster?

46:04What's the cause? What's the effect? You don't really know that because the mechanism, it's just an epidemiological study with no mechanism in it. So we also need to know about how saturated fats affect our plaque form, in our arteries. We need to know something about how carbohydrates in the banana cause our blood sugar levels to rise. We need to know a little bit of this stuff. And just like you were talking about how your mother taught home economics, when I was taught chemistry in school, why did they not teach us chemistry when it related to nutrition? Instead, we learned about, I don't know, we learned about petrochemicals and stuff like that.

46:43I mean, I loved chemistry in school, but none of it was actually applicable or practical. Why don't we just teach, when we teach basic science, why don't we teach it about health? I mean, including to medical students. Why don't we do that? We just don't do that. So this knowledge is, we consider it arcane, but it doesn't have to be that way. We just, that's the way we've created the system. We'll be right back after a quick word from our partners. What if the real question isn't where you're going, but the adventures you experience along the way. It's time to set your sights higher. On peaks still to be climbed, rivers still to be crossed and greater dreams to pursue.

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49:53Talking about valuable knowledge. Obviously, people can read FedUp. They can read some of your previous books. You've been on the podcast before. Your books are excellent. Your knowledge is incredible. They can look at these studies. they can think deeply, but they also have a full-time job and three kids and aging parents and challenges everywhere. So are there some simple questions that as soon as they've listened to this podcast, when it comes to their next meal or their next trip to the supermarket or their next conversation with their kids, are there a bunch of valuable questions that we should be asking ourselves when it comes to our diet that can have the biggest kind of instant impact to to what we start putting in our mouths.

50:34You know, there are so many studies I summarize in the book. And one of my favorite was a study done at Stanford. I mentioned it in the book, where they just told people, just cook your food at home. I don't care what you eat. Just cook your food at home. Don't buy prepared food. And the results were incredible. People lost weight and were really, you know, the health benefits of this non-diet, right, was just extraordinary. I mean, if there's one thing, just try to cook your own food. I mean, you can do that. And when you do that, guess what? You're probably going to end up, you know, getting a reasonable variety.

51:11You're probably not going to get this crappy UPF stuff. You'll probably eat a lot of plants. You're probably not going to add – because when you cook your own food, you don't add massive amounts of sugar and fat because who does that, right? There's still going to be some fiber in your food. You'll probably end up eating a reasonable diet. I mean, that's probably the easiest thing to do. Try to cook your own food. And even if you're stressed, I mean, I'm no different. I mean, I have a busy job, et cetera. Come home, it's 6 o 'clock. Oh, my God, what am I going to do, right? But instead of, like, what's wrong with a can of beans, right?

51:47Just take a can of, fry an onion, can of beans, cook some rice. I mean, beans and rice fed most of the world. I mean, it's not the most glorious dinner, but it works, right? And you add some spices and whatever. There are all kinds of ways we can do that without a lot of expense and time. But it's so convenient. There's that frozen such and such. You just put it in the microwave, you press the button. It is faster, it is easier. um that's true but what i love about you is that what you haven't said is oh the new daniel lieberman ready meals that you can microwave i'd make more money well that's exactly the point you would make more money but i think the reason why people should listen to what you have to say is because apart from the fact that we're very happy to promote an excellent book you're not here trying to make money out of people by guiding them down a path that is dangerous and actually i think because I was sitting here thinking what is the thing that we can talk about that brings the most value to the audience really simply and I kind of thought we'd have like 20 questions you should ask yourself before every meal but actually what we've broken this down to is did you cook it?

53:05do you know what's in it? are you happy with what's in it? I mean if that's all we ever ask ourselves about the food that goes into it you're probably 80 % of the way there yes yeah I mean look which is probably enough it's for most people it's pretty good you know I mean me i'm i'm not a big fan of animal foods i mean they have their place in our diet but if you eat if you try to go like an inuit or like a carnivore dieter you are putting yourself at risk according to the data so what's dangerous about a carnivore diet because they were very popular not long ago and probably still are in some places oh absolutely i get i get a lot of angry emails every day from carnivore dieters they don't like me um because look here's there are several we're talking about gold quality randomized control studies, right?

53:49There are several studies where there are prospective studies where they looked at, for example, the Harvard, the nurse's health study, where they looked at, this has been going on for 30 years now. There's a huge amount of really high quality data. Every serving of meat, which I think they define as 84 grams, 84, not 85, not 83, 84 grams. But anyway, every serving of meat, 84 grams, increases your risk of dying in a given year by, I think, 13%. 13? 13. Yes. What? 13%. Not in a particular year, but over the course of the experiment. Every? And you double that. It more or less doubles your mortality risk.

54:34So there are several studies which show that the more meat you eat, the greater your chance of a wide range of diseases and just basically dying. and there's a dose response effect and this is based on large amounts of data now look, we evolved to eat meat it's normal to eat meat, meat is nutritious I mean, carnivore diets are not entirely crazy you can survive on an all meat diet because meat is extremely nutritious but meat has we don't entirely understand it all but meat, for example on red meat, there's a what's called a glycoprotein so these are these little proteins that stick off every single cell and they've got a little sugar on them.

55:13So glyco is sugar protein, right? It's like a little forest sticking off every cell. We have a particular, red meat has a particular kind of glycoprotein which we don't have and our immune system doesn't like. And we're the only species that has it. And by the way, this amino acid change is from a gene called CMAH which evolved 2 million years ago. And if you put this gene in a mouse, it doubles how far it can run. Yeah, because it increases mitochondria. density and whatever. So it's part of my, you know, but anyway, it's part of, so there's an immune response, right? So we think there's, this is a hypothesis, right?

55:48Because we don't know all the mechanisms, but we have an immune response. So red meat is unquestionably associated with higher rates of cancer. There's just, the data are unquestionably clear about that. And cancer is often related to immune function. There's another process. There's a protein called carnitine, which is in meat, which our guts can turn into something called TMAO, which has been shown to cause heart disease, although it's a little complicated because fish can also have TMIO in it. So we don't entirely understand all this stuff. But nonetheless, we have mechanism and we also have epidemiological data.

56:19Now, does that mean you should cut meat out of your diet? Only if you want to. But should you be eating a lot of meat? It's probably putting yourself at risk, but you're not going to find out until 30 years from now. So are you going to just eat based on your tribe or are you going to eat based on the best scientific evidence? And you can disagree with me and that's fine. You can decide. That's okay. This is my reading of literature. And I would say that the vast majority of people who study nutrition believe this. And of course, we're also in a world of skepticism towards science. And there's a lot of skepticism towards people like me.

56:52Look, I'm a Harvard professor, right? I'm part of the elite. I'm in an ivory tower.

57:00I probably believe in vaccines and all that kind of stuff. What? So there's a kind of an anti-science skepticism out there combined with also a kind of pseudoscience, right? Which where we cherry pick the data and maybe I'm cherry picking the data and that's fine. People have every right to disagree with me and that's why I wrote the book. You can come up with your own conclusions. I've done my best. I've tried to explain what I think and the book is filled with references so you can look up every fact and look up the reference in the literature which you can probably get free online. there's no simple answers to this stuff.

57:36And nutrition is a complex science. Look, here's the other problem. One is that it takes decades for a particular diet to have a real effect on our health. So that's one problem. The other is we can't do the experiments that we'd really like to do. Like let's say we really want to do the definitive experiment on whether meat is bad for you. So what I could do is I could get a whole bunch of twins and I get one set of twins and I'll make them eat an all-meat diet and another set of twins and I'll never let meat pass their lips. And then I'll have to then make sure that they exercise the same amount, don't smoke, eat exactly.

58:14Everything else has to be similar, just the meat. And then I'll have to wait 60, 70, 80 years to find out the result. It's never going to happen. We can't do it that way. So we have to rely on a variety of sources of data, epidemiological studies, mechanistic studies, et cetera, and put them together. And so that feeds skepticism. And I understand the skepticism because there is no perfect study. And you can easily find a study that disagrees with me. You have to look at the bulk of the studies, put them together, and then interpret them yourself. And that's why it's difficult. And can I ask if it's possible to, if someone's listening to this, like me, who eats a lot of red meat, is it possible to unpick what damage might have been done or what you've done thus far by changing your diet I mean there's never too late to change I don't know so much about look people change all kinds of aspects of their physiology by changing their diet and their exercise one of my favorite studies is from the it's called the aerobic center longitudinal study you know Kenneth Cooper you know the word aerobics he invented that word and this is a study that's been going on since 1970, I believe.

59:29I can't remember the exact year, but since the seventies. And they've studied a lot of people over a long term. And one of the studies they did was they looked at people who are always fit, people who are never fit, and people who suddenly realized, oh my God, I better start exercising and got more fit at partway during their life. And guess what? The results are exactly what you expect. People who are always fit do the best. People who are never fit do the worst. And the people who get more fit do better. And and they improve their health a lot. And I'm sure that's true for diet. I don't know if those, again, those studies are harder to do for diet because one of the problems with diet is that every time you eat something, you tend not to eat something else.

1:00:08And that was the problem with the low-fat diet. A lot of people cut fat out of their diet. So what do they eat? They eat lots of sugar and processed foods, which the big companies were happy to give us. And it turns out those are worse for you than the fat, right? So you gotta study replacement, right? But another example is seed oils, right? There are a lot of people who are worried about seed oils. There's a story out there that was started, I think, by the paleo diet, or the paleo diet picked up on it, that since we never evolved to eat seed oils, which are rich in a kind of fatty acid called omega-6, it sounds all very complicated.

1:00:48It's actually not that complicated. Remember in the Greek alphabet, omega is the last letter in the Greek alphabet. but omega-6 means that six carbons away from the end, there's a double bond instead of a single bond. That's where the kink in the fatty acid is. And omega-3 fatty acids, that kink is three carbons away from the end. Not too complicated. It's a little bit complicated, but not too complicated. Anyway, so fish and things like that have a lot of omega-3 fatty acids. Seed oils tend to have a lot of omega-6 fatty acids. and omega-6 fatty acids can be turned into inflammatory molecules like prostaglandins, which give you a headache, for example.

1:01:34That's true. But guess what? There are experiments where they feed people omega-6 fatty acids and then find out if they're manufacturing inflammatory molecules. They don't. The process could happen, but it doesn't happen. And furthermore, big, big, big studies show that if you feed people any kind of polyunsaturated fat that has omega-6 fatty acids compared to people who eat saturated fat, they do better in almost every single health category you can think of. So the epidemiological data is there. The mechanistic data is there. There is a concern, but the science doesn't back the concern. At least the science that I've seen.

1:02:15But you need to read a lot of studies to get to that. And of course, I summarize them all in the book. And in the book, as you've gone through the process of researching and writing it, is there a belief that you once held that you've now abandoned? Well, I mean, we started talking about my mother, right? And I grew up to fear saturated fat and to think it was like an enemy. And now my attitude towards saturated fat, it's neither friend nor foe. you're always better off having an unsaturated or mono or polyunsaturated fat than a saturated fat. But, you know, I put butter on my whole wheat bagel in the morning.

1:02:59I love cheese. You know, I mean, I do eat, I just don't eat a huge amount of it, right? So, you know, or I could go on. There are probably plenty of other examples, right? Yeah, of course, you can't study the stuff and not, or salt, for example. I used to think that you should basically, you should always reduce the amount of salt. Well, it's more complicated than that. If you're hypertensive, it's probably important. If you have high blood pressure, it's pretty clear that you should lower your salt. But if you don't have high blood pressure, it turns out there's kind of a U-shaped curve and the kind of moderate amounts of salt turn out to be, actually people do better on it in large-scale studies.

1:03:36Some, but not all studies. So this is still an area of controversy, and I'm not sure that the last word on salt is out yet. So there's a lot of aspects of diet and nutrition that we're still trying to figure out. And that's a battle that my wife and I constantly have. She's always like, get rid of the salt, get rid of the salt. And I'm like, it's fine. I'm normal intensive. I'm not hypertensive. It's fine. And she wants me to remove the salt. So I sneak the salt. And who wins? Oh, you. Okay, you sneak. You're scared. I just use the salt. Quite right. I think the book's amazing. it's lovely to have you back on the show we could talk for a long time I think one of my big concerns is this world we live in now that seems to want to ignore the data or ignore scientists or ignore the science and believe that actually conspiracy theories is the way forward and I think it's great that you've in the book you cite so many studies you do so much research and all of it as it would be as it's a book from you is about our evolution and where we've come from and I couldn't recommend the book enough before we finish though we've got some quick fire questions for you if you would indulge us and you would like these because they're in partnership with our partner Vitality who is a life and health insurer who nudged people's healthier lifestyle choices.

1:04:47Three non-negotiables when it comes to your diet. Don't eliminate. Moderation is better than elimination. Very good. Try to eat mostly plants and try to decrease your consumption of ultra-processed food that you could not make in your own kitchen. What's the greatest piece of advice you've ever received? Why? Do what you really care about. You know, life is short, right? And so many people just, you know, try to make the world a better place. Those are the things that I think make us the happiest, right? Trying to help each other, be compassionate, help other people. that that makes that's that's that's the most important thing we can do all of us what's your biggest strength maybe curiosity i don't know i don't know you'd have to ask my wife your greatest weakness impatience advice to a young daniel just starting out in life i've had a pretty lucky blessed life but um i i i would say that if i were giving myself advice when I was young, be more open-minded.

1:06:01I think just sometimes as a, you know, too quick to judge. What's one change in your life that's maximized the impact you've had in both life and work? I would say running marathons. So when I started studying the evolution of running, I like to run, but I would run like four or five miles. and as I started working on evolution on the on the you know the born to run paper and and and whatever I started getting into longer distances and got invited to you know give and and and I started the first time I ever put a number on my chest was running a marathon and it was life changing um uh I I really um uh you know there's a you know I was okay but there's something about getting fit, like really fit, as opposed to just sort of a little bit fit.

1:06:54Yeah. That unless you've experienced it, it's hard to explain, but it's been really life-changing. And I think, and because of my interest in physical activity, that's why I wrote the book on diet. I mean, the two are related. So yeah, getting really fit, really, I think, was life-changing. And finally, what does high performance mean to you? Doing your best. Well, I think you've done your best with FedUp. Oh, thank you. You can find out more about Vitality at vitality.co.uk, the life and health insurer that uses a behavior change program to incentivize healthy lifestyle choices. Never was there a more apt partner for the quickfire questions than when we're talking to you when it comes to behavior change.

1:07:41FedUp is available now. Daniel Lieberman, thank you so much for your time and your wisdom and the effort you put into another great book. Oh, it's my pleasure. Thank you. Damien. Jake. I'll tell you what stopped me in my tracks in that conversation. I mean, 84 grams of red meat increases your chance of dying at any point by 13%. I know. What? What? I know. I'm surprised I'm still alive, the amount of steak I've got through in my life. But I think it's, again, that's a really good example of the kind of world we're living in where everywhere I look, it's like eat steak, get your protein in, eat red meat, power up, get strong, get in the gym.

1:08:23And then Daniel's there going, you can do that, but in 30 years' time, it's going to increase your chances of mortality. Yeah, yeah. It's scary. I think the big thing I took away from it was like be a fox. Think in a flexible way. Don't get caught up with just one idea. There's no silver bullet. There's no hack. Yes, but the problem with that is you still don't know what to think, though. Do you know what I mean? Yeah, but I like the fact that it was like, be sceptical, ask better, deeper questions. And that applies to nutrition as much as it applies to life in general, of don't just take things on the surface level, push a bit deeper, go deeper, try and explore it, be curious.

1:08:59And that's what I took away from it, that I think if we can all be a bit more curious about where we're getting our information from and does it work for us. and I see what you're saying and I understand it my problem with that is I think every time I'm curious about something I look at information I don't know what to trust and even when you try and work out whether you should trust the information it's hard to know whether to trust what you're being told about trusting it because it's hard so actually when Daniel's like listen cook it yourself so you know what's in it you can be as curious as you like you can be as much of a fox as you want to be and by the way you are a fox thank you very much but just cook your own food yeah because it's because then it's almost it's also like it's giving you back control like you can still load the salt load the sugar load the fat like but at least you're making that decision yeah whereas what I hate is when you I don't know you go and have some what is it my daughter's obsessed with at the moment acai bowls oh dad can you take me to Norwich we can have an acai bowl together and she's like oh yeah they're really healthy how do you know because they're loaded with peanut butter this and this sort of sauce and this and it's all probably all crap but my daughter at 13 has been told that it's a really cool thing to eat so she does whereas it's not about being a fox there necessarily because you can try and get the info but will you be lied to I think it's more about yeah be a fox but also take control to cook your own food yes I like that and one of the other things I take away like that idea of just cook your own food, it reminds me of like whenever you see like great coaches, great coaches have the ability to take the complex and make it accessible and simple.

1:10:46And I think that advice of going, there's that much information out there, try this and see how you get on with it, of cooking your own food. That to me gives him real credibility. Exactly. And he's also not trying to sell a Daniel Lieberman gut shot or a Daniel Lieberman GLP2 injection. Do you know what I mean? And he's like, yes, he's trying to sell a book, right? Let's be totally honest. He's coming on here so people hear him talk and buy his book. But the book is valuable. And there's no sinister ulterior motive from Daniel. No. Which you find from others. And when I read the book, one of the things I always respect is when people put a comprehensive index, this is where I've got the information from.

1:11:27And he will argue against himself in that as well, which shows that curiosity of going, here's one argument, but here's the alternative which then just makes it credible because he's not trying to give you that silver bullet that hedgehog response of follow this way because this is the only way that's great thank you brother thanks mate loved it there were loads of amazing conversations with nutritionists health wellness food experts you can find them all in the high performance archives please if you thought there's some real value in what Daniel had to say today just send this to someone just share this conversation please like please subscribe please hit the follow button and please remain humble, curious, and empathetic.

1:12:06And we'll see you next time.

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