What Should We Eat? Evolution, Diet, and Health

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This is Origin Stories, the Leakey Foundation podcast.

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I’m Meredith Johnson.

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What should we eat?

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It’s a simple but confusing question, and there’s a lot of contradictory advice.

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Should you eat vegan, paleo, low-carb, low-fat, high-protein?

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Do we avoid saturated fats or put butter in our morning coffee?

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With so many diets claiming to be the key to better health, weight loss, and longevity, it’s hard to figure out what to do.

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Today on the show, we welcome back paleoanthropologist and author Daniel Lieberman to talk about food, health, human evolution, and his new book, Fed Up, What Evolution Reveals About Food, Diet, Health, and Eating Well.

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The book brings insights from evolutionary science, physiology, anthropology, medicine, and history to help us make sense of the world of diet and wellness advice and give us some tools and knowledge so we can make more informed choices about what we eat.

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Dan is a professor at Harvard University and a founding chair of their Department of Human Evolutionary Biology.

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He’s a Leakey Foundation grantee and a member of our Scientific Executive Committee.

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Dan, it’s great to have you back on the show.

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It’s a pleasure.

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Thank you.

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So why don’t we start with the question you start your book with, what should I eat?

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I mean, that’s really what the book is about.

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How many times a day do you or I, or like people listening, ask themselves, what should I eat?

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And I really started the book because that’s a very modern question that we never evolved to ask, let alone answer.

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I mean, when I walk into a supermarket, a typical American supermarket has about 40,000 different kinds of food.

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And a large percentage of those foods are pretty weird foods, right?

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They’ve been boxed and packaged in factories and processed in all kinds of ways.

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And so we’re actually choosing foods we never evolved to eat.

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But if I was a hunter gatherer, and of course we were hunter gatherers for most of our existence, hunter gatherers, they don’t ask themselves what they’re going to eat.

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They eat what they hunt and what they gather.

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And if you’re a farmer, you eat what you grow.

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So this modern industrial problem of what should I eat is something entirely novel for which we never evolved.

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And obviously, we do a pretty bad job in many parts of the world.

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How does an evolutionary perspective help us figure out or do better with the question of what we should eat?

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Well, I mean, evolution doesn’t answer the question entirely.

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But my favorite saying, and I say it all the time, is that nothing in biology makes sense except in the light of evolution.

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And that’s because we weren’t designed, we weren’t engineered, we evolved.

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And if you want to understand how and why our digestive systems work and our nutrition works and the association between what we eat and our health works, an evolutionary perspective is an important element.

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But of course, you need to combine that with other kinds of data, with biomedical data, with nutrition, with physiology, with studying the microbiome.

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There’s a lot of other forms of information, but evolution gives us the framework with which to interpret it.

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One way people kind of take the framework of evolution and try to answer questions about health is to look at living hunter-gatherers, people living that lifestyle now.

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In your work, you’ve spent time with hunter-gatherers.

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How does what they need to know about food compare to what people who get their food from grocery stores need to know?

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If you’re a hunter-gatherer or farmer, you need to know a lot to get your food, right?

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I’ve had the privilege of going out with hunter-gatherers.

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You don’t just walk out and just pluck berries.

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You need to know a lot in order to hunt and gather food, to find out where it is and know what to eat and how to process it.

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I mean, that’s their job and it requires an enormous amount of knowledge.

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We don’t need to know anything these days about how to get our food, right?

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What we need to know in the modern world is how to choose our food, because that’s the problem that we face.

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And so I tried to put in the book all the information I think anybody in the modern world needs to know about how to choose their food.

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And also for the book, I thought it would be sort of fun to try a lot of these diets.

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And I sort of matched diets to the kind of the history of diets.

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So I started off with a raw food diet, did a paleo diet, et cetera, et cetera.

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Not so much to test their effect on my health, because I didn’t want to eat them for years and years.

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I couldn’t.

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So I’m not pretending this is biomedical data, but rather to kind of get a sense of what these different diets are like, because I don’t know, I’m curious.

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And just like I tried barefoot running when I was studying evolution of running, I thought I should try different diets.

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I like participant observation.

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I think you should try what you study.

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I like that.

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And you got your wife, Tonia, to go along with it.

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I really enjoyed that in the book.

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Yeah.

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My wife tried the diets with me and that added a lot of, I mean, first of all, I made it because we eat dinner together.

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So that was important, but also she’s very funny.

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Very funny.

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So what was it like for you to eat these diets?

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Some of it sounded pretty not fun.

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I mean, some were okay and some were a challenge.

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I mean, the raw food diet was by far the hardest.

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My wife, I mean, first of all, we were hungry all the time because you don’t get a lot of nutrients.

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I mean, cooking gives you more nutrients from your food.

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And boy, is that true.

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When we were trying to eat all these raw foods, I was just constantly hungry.

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And I was just thinking about food all the time.

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And we’re spending a huge amount of time just processing our food.

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So that was the worst.

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And after a few days, my wife got actually kind of depressed and sad.

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And as I described in the book, one day she disappeared in the morning, came back looking happy.

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And she confessed that she’d gone out and gotten a bagel.

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And I made it only a day longer.

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And then I just gave up.

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It just wasn’t fitting my life.

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The paleo diet, I was able to tolerate for two weeks, but it was pretty frustrating.

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Let’s talk about the paleo diet and a study you and your colleagues did at the start of the COVID pandemic.

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Yeah, that was actually one of the starting points for the book because yeah, during COVID, the lab was closed and I had an undergraduate in my lab who was going to do an experimental project.

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And of course you couldn’t do it.

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So we thought, okay, let’s scour the literature and find all the highest quality data on what tropical hunter-gatherers eat.

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So we decided to focus on tropical hunter-gatherers because that was the vast majority of hunter-gatherers and compare that to the paleo diet because the paleo diet has some detailed prescriptions about what you should eat, supposedly based on what hunter-gatherers eat.

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And it was based on this famous atlas by a guy named Murdock, who tried to put together all the data on hunter-gatherers, but a lot of the data aren’t very good.

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So we thought, let’s just focus on the high quality data.

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And it turns out there are 12 different populations for which their data are good enough that we can actually say something real.

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These are when people actually studied and measured and quantified what it is that people actually ate.

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And what we discovered was that first of all, not a single one of the hunter-gatherer diets actually resembled the paleo diet in any way.

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And furthermore, even more importantly, they were all over the place.

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I mean, there are some hunter-gatherer populations that eat almost all animal foods and some that eat almost entirely plant foods and everything in between.

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And what it emphasized to me was that we didn’t evolve to eat a single diet.

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That’s just nonsense.

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We evolved to eat anything necessary in order to survive and have offspring.

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The basic equation of life is that, is food in equals babies out, right?

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And so we were selected not for health.

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We didn’t were selected to live to be 80 or 90 or a centenarian.

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We were selected in order to get enough food so that we can have as many offspring as possible, who in turn survived to have offspring.

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That’s what we’re adapted for.

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And so if you’re eating a paleo diet, remember that what we’re adapted for is reproductive success, not health.

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And the other, of course, problem with the paleo diet is that like a lot of diets, it’s based on exclusion.

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It’s based on eliminating foods.

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And so the paleo diet bans all grains, right?

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It bans all legumes.

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So no peanut butter, which by the way, is by far my favorite food.

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And it bans dairy, even though of course we’re mammals.

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We evolved to drink milk when we were very young.

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And we also found, and also other people had already published too, that this is just, well, it’s just wrong.

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I mean, for example, in the Kalahari Desert where the San live, right?

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The famous large group of hunter-gatherer populations in the Kalahari.

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The second food they eat the most is something called the marama bean, which is a legume.

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So don’t tell me they don’t eat legumes.

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And we have plenty of data from archaeological sites elsewhere that hunter-gatherers were harvesting grains.

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We have remnants that stuck onto the teeth of Neanderthals that they’re eating grains.

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I mean, it’s just silly.

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Hunter-gatherers evolved to eat absolutely anything they could, not for the sake of their health, but for the sake of just surviving and getting through the day and feeding their families and having as many offspring as possible.

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And so that’s the basic naturalistic fallacy behind the paleo diet, that there is a paleo diet and that we’re adapted to eat those foods for the sake of our health.

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Right.

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Our ancestors wouldn’t have just like passed up a tuber or some beans if they found them.

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Of course not.

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It’d be crazy.

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It’d be like, you know, like you’re giving me free money.

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I mean, why would I pass that up?

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So again, it’s kind of an oversimplistic view based on a misreading of the archaeological paleontological record, but also there’s some kind of fear-mongering that they have about what’s so-called anti-nutrients.

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Well, let’s talk about that.

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Can you explain anti-nutrients?

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Is this a real thing people need to worry about?

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Yeah.

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So anti-nutrients are compounds that are found in plants.

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Lectins, for example, which are very common in beans and phytates and oxalates.

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And there’s a bunch of these compounds and it’s true, they do bind to vitamins and minerals and prevent their absorption in the intestine.

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But guess what?

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When you cook your food or ferment your food, you pretty much bring them down to completely harmless levels.

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I mean, otherwise people who are vegetarians and whatever would be, we’d all be malnourished, right?

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All the people in the world who eat plants and clearly people aren’t walking around completely anti-nourished because they’re eating peanut butter and lentils and beans and whatever.

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They’re eating cooked beans and they’re eating cooked peanuts and they’re eating fermented soy and whatever.

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So this is fear-mongering.

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So looking at our evolutionary history, the human strategy seems to have been that we eat almost anything, right?

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We’re not sticking to one kind of food.

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Yeah.

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So one of the things that’s sort of interesting about humans is that we haven’t ever stopped eating anything our ancestors ate.

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What we’ve simply done is we kept adding things to our diet.

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So we evolved from chimpanzee-like creatures that ate mostly fruit and some herbs, and we still eat fruit and herbs.

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That’s what I had for breakfast.

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I had fruit.

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For dinner, I’ll probably have a salad.

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And then later on, we added tubers and underground storage organs.

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That’s what those australopiths were eating a lot, like Lucy and whatever.

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And we have potatoes and ginger and all kinds of other underground storage organs, which are still very important parts of our diet.

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And if you’re a hunter-gatherer in Tanzania, like a Hadza, for example, tubers make up an enormous component of their diet and they’re very healthy.

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And then we, at some point, around 2 million years ago or so, started eating meat.

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And so meat and animal food started becoming a really major part of our diet.

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And then we added fish and we added all kinds of other things.

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So we haven’t replaced anything.

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We just kept adding more and more.

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And then the other thing, of course, we started doing was cooking and doing other forms of food processing.

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And the consequence of this evolutionary history, especially our abilities to process food through cooking and other means, have made us and made hunter-gatherers the ultimate omnivores of the animal kingdom.

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It’s astonishing the diversity of foods that humans have evolved to eat.

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And that’s part of the secret of our success.

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But again, we didn’t evolve to eat all these foods for the sake of our health.

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We evolved to eat these foods for the sake of reproductive success.

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Yeah.

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And you just mentioned meat eating coming along later in our evolutionary history.

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But meat’s kind of the big thing people think about when they want to try eating an ancestrally inspired diet.

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It seems that people are really stuck on the idea that people in the Paleolithic ate mostly meat.

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Yeah.

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I think it’s partly because people have this, it’s part of this Neanderthal fetish that people have, right?

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People think about, you know, Neanderthals and Arctic peoples.

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And it’s true.

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If you live in the Arctic, there aren’t a lot of plants to eat.

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So guess what?

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You’re going to eat a lot of animal products.

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And of course, Neanderthals living in Ice Age Europe, there were times when, yes, of course, they’re a bit like the Inuit.

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I mean, there’s just not much else for them to eat.

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But don’t forget the Ice Age kept changing, right?

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125,000 years ago, right?

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When Neanderthals were whooping it up in parts of Europe and especially in England, there were hippos cavorting in the Thames in London, right?

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Don’t tell me the Neanderthals are just eating only meat in those time periods, right?

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So we have a kind of cartoon characterization of Neanderthal diets based on what they were eating in the very worst times when they were living in Europe.

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But the Neanderthals were probably as diverse in terms of what they ate as just about everybody else.

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The idea that they were only eating lots of meat is just, again, just not what the paleontological and archaeological record tells us.

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Well, why do you think the paleo diet or the idea of eating like our ancestors is so appealing?

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We like simple ideas and the naturalistic fallacy is a simple idea.

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You eat what your ancestors eat.

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Eat what your grandmother ate.

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And all of these ideas are based on a grain of truth.

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I mean, there is some basis to the idea, right?

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We are adapted to eating certain things and we’re not adapted to eating other things.

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We’re not adapted to eating fugu liver.

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There are all kinds of things we’re not adapted to eating and which we shouldn’t eat.

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But that’s just an oversimple way of thinking about it.

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And the fact of the matter is just because our ancestors did something doesn’t mean it’s good for us for our long-term health.

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And just because they didn’t do something also doesn’t mean we shouldn’t do it.

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I mean, they didn’t sleep on mattresses and they didn’t have refrigerators and they didn’t brush their teeth and I could go on, right?

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Let’s jump forward in the history of our diets and talk about the rise of farming and how farming changed what we eat.

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Yeah, so farming is fascinating because in many ways it’s been given a bad name by some evolutionary biologists like, you know, Jared Diamond called it the biggest mistake ever made by humans.

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And in some ways this is correct, right?

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With farming came a much greater increase in disease because once people settled down and started farming the foods that they formerly gathered and they domesticated some of the animals that they were formerly hunting, first of all, they started living in the same places all the time permanently.

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So they had permanent villages.

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And secondly, even a Neolithic farmer can gather way more energy than a hunter-gatherer can.

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And so with the origins of farming, you also get increases in population size and population density.

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And so the combination of people living in permanent villages with their animals in large populations at high densities, all of a sudden you get a fluorescence of infectious diseases.

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Now, of course, infectious diseases occurred prior to the origins of farming, but with farming, things got way worse.

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And that’s when you really begin to see a decline in health.

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And so you have high rates of infant mortality, which undergathers also have, but you also have high rates of infectious disease mortality throughout the lifespan.

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And so life really got nasty, brutish, and short really after the origins of farming.

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And of course, the other problem with farming is that you’re dependent on your crops.

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So when hunter-gatherers who live at very low population densities, I mean, extremely, you just have a few people in all of Manhattan if you were a hunter-gatherer, like five people for all of Manhattan, imagine that.

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And all of a sudden now you have these big villages and they’re dependent on their crops.

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And if you have a drought for one year or even sometimes two or three years in a row, you’re screwed if you’re a farmer, right?

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There’s nothing to fall back on.

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And so with farming, you get a serious increase in famine and malnutrition from infectious diseases and other sorts of problems.

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So farming allowed people to have more babies.

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So remember the equation of life is food in equals babies out.

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So from an evolutionary perspective, farming was a great idea because remember, it’s all about reproductive success.

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From a quality of life perspective, it’s more complicated.

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A lot of that doesn’t sound good, but were their diets healthier?

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Were people getting better food with farming?

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Glad you asked that.

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It’s interesting.

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So when people talk about farming diets as being nutritionally poor, I think they’re equating modern agricultural diets with ancient agricultural diets.

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For example, let’s take the first farming diet was a Mediterranean diet.

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Well, Mediterranean farmers, they weren’t eating refined white flour.

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They were eating whole grain flour, which is really quite healthy.

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And every farming culture on the planet, whether it’s the Mediterranean and Asia, Africa, they all figured out how to combine cereals with legumes.

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So you get a complimentary protein.

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So think about the classic corn and beans or rice and beans like soy and rice, or in the Middle East, you’d have legumes like lentils and chickpeas with bread and other products made from cereals.

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When you combine those, it’s magical, right?

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You get basically all the protein, the amino acids that you need.

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And then you combine that with vegetables because you always backed it up with a variety of vegetables and seeds and nuts and fruits.

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And you have actually a pretty healthy diet.

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And a good example, again, is the Mediterranean diet, which is probably the best studied because it’s European.

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So there’s a little Eurocentrism involved.

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But the Mediterranean diet, if you’re going to go epidemiologically and mechanistically on one diet that’s been best shown through numerous study after study after study to be good for your health, it’s the Mediterranean diet, right?

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And of course, the Mediterranean diet today is a little bit invented.

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It’s not necessarily what farmers ate, but it’s not completely off.

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And obviously, a traditional Asian diet, think about Japan is where people have the greatest lifespan in any country in the world, right?

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The traditional Asian diet is obviously extremely healthy, traditional Mesoamerican diet, I could go on.

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Well, on the topic of lifespan, another diet you wrote about in the farming diet section of your book and that you ate for a few weeks is the Blue Zones diet.

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Can we talk about that?

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Yeah.

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So the reason I did the Blue Zones diet is that, of course, there are other farming diets apart from the Mediterranean diet.

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And the Blue Zones is basically an attempt to look at all these traditional non-industrial diets and sort of what their commonalities are.

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And on the one hand, I kind of like the diet.

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It was a pretty sensible, reasonable diet.

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Don’t eat a lot of processed foods with added sugar and eat lots of beans.

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And it’s basically a plant-heavy diet.

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It’s reasonably sensible.

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It also has some social aspects to it.

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Don’t eat alone.

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And what I didn’t like about the Blue Zones diet is the claim that, because it’s marketing, the idea is that there are these five little parts of the world called Blue Zones, where supposedly a large percentage of people live to be centenarians, live to be 100 years old.

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And well, first of all, if you look at the data, if you believe the data, there’s still only like six people out of 1,000, 10,000 are living to be this age.

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So they’re basically saying, if you eat this diet, you’ll be like a statistical outlier.

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And furthermore, yeah, there may be six people out of 1,000 or 10,000 in this population living to be centenarians.

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And that’s twice what it is in the United States, which is three.

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But it’s statistical nonsense to argue that this is the way things work.

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And furthermore, look at the, again, Japan is where people live the longest.

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And then you should eat like the Japanese.

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And you know what the country which has the second greatest longevity in the world?

260
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It’s Switzerland, right?

261
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Where people are eating cheese and lots of dairy and meat and chocolate and whatever.

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So obviously there’s a little bit of marketing.

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And here’s another issue that was really funny.

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So there’s a demographer in Oxford named Saul Newman, who published a paper where he actually spent, must have been an enormous amount of effort, and actually looked up the birth certificates of these individuals and found out that only about 18% of the people in these supposed blue zones even have birth certificates.

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So we don’t actually know how old they are.

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And he posited that a lot of these people are basically committing insurance fraud.

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Oh my goodness.

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So what does a diet like the blue zones diet tell you?

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So the blue zones diet, on the one hand, has a lot of sense to it.

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But on the other hand, I found it a good example of the kind of simplistic marketing that is just so common in the diet world, which is that you try to take one big idea, like eat like these people and you never get heart disease.

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Don’t eat this and you’ll never get metabolic syndrome.

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Don’t eat this and you’ll never get cancer.

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We all have these simplistic, over-simple ideas.

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And really, if my book is any one argument, it’s a cri de coeur that we should stop this oversimplification of diet.

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There is no such thing as an optimal diet.

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There is no one perfect diet.

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We didn’t evolve for one perfect diet.

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And this evolutionary perspective and the biomedical data all converge to tell us that we evolved to eat everything.

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We didn’t evolve to live to be 100, although some of us do manage to do that.

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There are healthier diets than others, but it’s not based on one simple idea.

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Everything has trade-offs.

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So now we’re here in an era of industrialized food where there are lots of trade-offs, like for convenience and time and expense.

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And at the same time, a lot of us are just not feeling great a lot of the time.

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Right.

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We’re all struggling.

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And we live in an environment that makes it very confusing and difficult.

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And I think a large part of that, of course, is from ultra-processed foods, which is another oversimplification.

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So the idea behind an ultra-processed food is if it’s made in a factory, you can’t make it at home.

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It must be bad for you.

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And again, there’s a lot of truth to that, actually.

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I mean, if you look at the rise of obesity and a lot of these metabolic diseases and cancers that we’re experiencing, they correlate very well with these processed foods, because these foods really are unhealthy.

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We don’t still know exactly why, right?

293
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And there’s probably multiple factors.

294
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So one is that these foods are just junk food, right?

295
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The nutrients have been stripped away through processing.

296
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So the fiber is gone as well.

297
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And fiber is very important.

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They’ve had sugar added, and sugar really is bad for you.

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If there’s probably one number one cause of diet-related disease, it’s sugar, added sugar to our diets.

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No question about that.

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A lot of them have a lot of fat added, especially saturated fat.

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Saturated fat is never your friend.

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And then, of course, finally, the thing about these foods is that they’re engineered.

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I mean, when I say engineered, I really mean it.

305
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They’re engineered for them to be addictive and appetizing and appealing, right?

306
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So we eat a lot of them, right?

307
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So the combination of the fact that they’re junk food, the fact that they have serious additives that are suspicious, and that they’re designed to be overeating, guess what?

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If you choose any one of these diets, it’s not a crap diet.

309
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You’ll probably do better.

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Yeah.

311
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But we haven’t talked about one of the main reasons people are searching for and trying different diets, which is to lose weight.

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Can we talk about that?

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One of the biggest problems with losing weight is that we never evolved to lose weight.

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That’s another incredibly important evolutionary insight, right?

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When we try to lose weight, ultimately, we’re reducing the number of calories that we have.

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But when you reduce the number of calories that you have, guess what?

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You get hungry.

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Your appetite goes up.

319
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And it’s extremely, extremely hard to fight your hunger, right?

320
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You have all kinds of mechanisms in your body.

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You have ghrelin that’s produced by your stomach.

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You have peptides that are produced by your gut.

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You have leptin, which is produced by your fat molecules.

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When your fat molecules shrink, the leptin levels go down and tells your hypothalamus and your brain, oh my God, we’re losing fat.

325
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You need to get hungry and eat more.

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There are all these different mechanisms are all acting together.

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And furthermore, to make things worse, because we never evolved to lose body fat, we have this kind of maladaptive mechanism that we just inherited, which is that when you gain weight, your body then considers that to be the set point.

328
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So when you start to lose weight, your body wants to return you to your previous weight.

329
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So it’s not the weight you had when you were 20.

330
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It’s the weight you had after you gained all that extra weight.

331
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And we don’t know why that’s the case.

332
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And nobody’s yet figured out how to turn that off.

333
00:25:25,900 –> 00:25:27,760
But that’s the real challenge with dieting.

334
00:25:28,440 –> 00:25:31,760
Nutrition and digestion and physiology and health are so complicated.

335
00:25:32,740 –> 00:25:37,340
We have to recognize that there are no simple magic bullet answers.

336
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And again, to go back to the beginning of this conversation, our ancestors had to know a lot how to get their food.

337
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We now need to know something about how to choose our food, because that’s just the world we live in.

338
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We have those nutrition facts labels on the back of all the foods we buy.

339
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How do we interpret them?

340
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How do we decide how to use that information?

341
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How do we decide, say, if you’re trying to lose weight, do you want to do a low carb diet?

342
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There’s science behind it.

343
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Do you want to do a low fat diet?

344
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Well, there’s also science behind that too.

345
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And the result is that since most diets fail, people then go from diet to diet to diet to diet, and they’re confused and they’re struggling and they’re conflicted.

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And there are all these influencers out there spouting nonsense, but there’s always, again, there’s always a grain of truth to their nonsense, right?

347
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And so we live in this very confusing cacophony of dietary information.

348
00:26:29,440 –> 00:26:37,420
And the solution is to A, educate ourselves, and B, not to fall into this kind of oversimple thinking.

349
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Well, so given all this and all the research you did for your book, what should- What do we eat?

350
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Yeah, what do we eat?

351
00:26:46,820 –> 00:26:50,480
Well, I think that, again, all of these diets have a grain of truth.

352
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The paleo diet has a grain of truth.

353
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We’re adapted to eating certain foods.

354
00:26:54,240 –> 00:26:56,020
We’re maladapted to eating others, right?

355
00:26:56,160 –> 00:26:57,500
They kind of get it wrong, right?

356
00:26:57,680 –> 00:27:02,780
But remember, we’re not adapted to eating these foods for the sake of our health, but for reproductive success.

357
00:27:03,140 –> 00:27:07,100
The low carb diet definitely has a serious grain of truth, right?

358
00:27:07,500 –> 00:27:08,420
More than a grain of truth.

359
00:27:08,480 –> 00:27:12,240
It’s based on some basic sound endocrinological principles.

360
00:27:12,480 –> 00:27:18,680
But low fat diets also have some important things to tell us, as do low calorie diets, right?

361
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If you want to lose weight, really, you do have to cut down on the number of calories you eat.

362
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So my perspective is, well, why do you have to pick one?

363
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Why not take all the best elements of all these diets and combine them, right?

364
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And you know what you do when you do that?

365
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You get basically a Mediterranean diet or some kind of traditional non-industrial farming diet, right?

366
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Where you’re not eating a lot of refined carbohydrates.

367
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So a traditional Mediterranean diet is not rich in sugar.

368
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It’s not rich in refined carbs.

369
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A traditional Mediterranean diet, a traditional Asian diet, a traditional Mesoamerican diet, a traditional African diet has healthy fats.

370
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It has lots of vegetables.

371
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It has fruits and nuts, and it’s not super calorie rich.

372
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And it’s also delicious, by the way.

373
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And so why do we have to pick one?

374
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These are all generally healthy diets.

375
00:28:08,880 –> 00:28:09,400
And guess what?

376
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They’ve also been studied the most, right?

377
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There was a study, for example, in Spain where they, I can’t remember the size of the study, but they’re like 7,000 people randomized in the study to either eating a normal sort of industrial diet versus half of them were assigned a Mediterranean diet.

378
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Some of them were assigned a Mediterranean diet, which had a lot of olive oil, and some of them were assigned a Mediterranean diet, which had extra walnuts.

379
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And guess what?

380
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They stopped the study after five years.

381
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Why?

382
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Because there was so much benefit to the Mediterranean diet, it was actually unethical to continue the non-Mediterranean arm of the diet because those people had many more heart attacks and other kinds of negative health outcomes.

383
00:28:51,780 –> 00:28:53,440
And that’s just one of many studies.

384
00:28:53,580 –> 00:29:06,880
So if you want to go based on just the published evidence, not based on what some person on YouTube or some book that you read, but you want to go based on peer-reviewed published evidence, you would pick something like a Mediterranean diet for your health.

385
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Can I also mention something?

386
00:29:10,100 –> 00:29:14,560
The other thing is that a lot of diets work because they claim to be like magic bullets.

387
00:29:14,940 –> 00:29:16,380
We need to be a little bit more honest.

388
00:29:17,000 –> 00:29:22,460
Some of these diets do reduce your risks, but none of these diets are magic bullets, none of them.

389
00:29:22,620 –> 00:29:25,400
And furthermore, there are other things you need to do as well for your health.

390
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Sleep matters, exercise matters.

391
00:29:28,940 –> 00:29:30,140
Stress matters.

392
00:29:30,460 –> 00:29:31,760
These are all important, right?

393
00:29:31,760 –> 00:29:35,020
And we should stop overselling any of these diets.

394
00:29:35,280 –> 00:29:36,420
Mediterranean diet is no exception.

395
00:29:36,660 –> 00:29:47,740
So when I’m touting all the benefits of the Mediterranean diet, don’t interpret me as saying that the Mediterranean diet is a surefire guaranteed quick fix to all your diet problems.

396
00:29:47,920 –> 00:29:48,380
It isn’t.

397
00:29:48,540 –> 00:29:52,720
It’s just of the various diets out there that we could pick, it’s one of the healthiest.

398
00:29:53,100 –> 00:29:54,360
Well, thank you, Dan.

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This has been really fun.

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My pleasure.

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As you know, I love the Leakey Foundation.

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You can find FedUp at your local library or bookstore, but we also have 12 copies to give away.

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It’s a great read and I think you’ll love it.

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To enter, just click the link in your show notes.

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It’s completely free to enter, open to U.S. residents 18 and older, and no donation or purchase is necessary.

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You have until October 12th to get your entry in and we’ll pick the winners at random.

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If you want to learn more about evolution, diet, health, and eating well, please join us for some upcoming Leakey Foundation lectures and events with Daniel Lieberman.

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We’ll be in Cambridge, Salt Lake City, and Houston in October.

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We’ll be at the Field Museum in Chicago in November, and we have two events coming up in San Francisco in December.

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I hope to see you there.

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Origin Stories is a project of the Leakey Foundation, a donor-supported nonprofit dedicated to funding human origins research and sharing discoveries.

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This show is made possible by our listener supporters with additional funding from Jeanne Newman, Camilla and George Smith, the Ann and Gordon Getty Foundation, and the Joan and Arnold Travis Education Fund.

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This episode was produced by me, Meredith Johnson, and Ray Pang.

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Our editor is Audrey Quinn.

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Theme music by Henry Nagle

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Additional music by Lee Roservere and Blue Dot Sessions.

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We’ll be back next month with another episode.

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Thanks for listening.