Why So Many People Feel Empty & The Truth About What Humans Should Eat

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0:47And I found that once you actually see the numbers, you look at your money differently. If you've ever wondered, where exactly is all my money going? I think you'll find Monarch pretty eye-opening. Write your own money story with Monarch. Use code SYSK at Monarch.com to get your first year of Monarch Core half off at just$50. That's 50 % off your first year at Monarch.com with code SYSK. Today on Something You Should Know. How summer heat can change your behavior, and not in a good way. Then, one of the world's leading experts on human potential reveals why so many people lack meaning and purpose.

1:37These days, about 30 % of young adults say my life feels meaningless, but that number's really been creeping up, and it's been creeping up a lot, especially since 2008, since the introduction of the technologies that have really occupied our lives. Also, how well can other people sense when you're nervous? And what are humans supposed to eat? It's often hard to tell. I teach anatomy and physiology at Harvard, and I look at the literature and I think, my God, how do I reconcile the fact that there are people who say I should be vegetarian versus the carnivore diets and the keto diets and the low-fat diets and the Mediterranean diet and the Blue Zone diet?

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3:41Get free shipping on your order and 365-day returns. Now available in Canada and the UK too. And when Quince asks where you heard about them, please let them know it was Something You Should Know. It's the best way to support our show. Something you should know. Fascinating intel. The world's top experts. And practical advice you can use in your life. Today, Something You Should Know with Mike Carruthers. Something definitely happens to people when the weather gets hot. And it's not good, so it's worth knowing about, and that's what we're going to begin with today. I'm Mike Carruthers. Welcome to Something You Should Know.

4:23If you pay attention, you'll notice how little things seem to bother you more when you're hot. People get more impatient in traffic, arguments escalate faster, and even simple tasks can feel surprisingly difficult. It turns out that's not just because you're uncomfortable in the heat. Heat can actually affect how your brain works. Research has found that high temperatures can impair concentration, slow reaction time, reduce your ability to process information, and make complex thinking more difficult. In one study, college students living in dorms without air conditioning during a heat wave performed significantly worse on cognitive tests than students whose dorms were air conditioned.

5:11Other research has linked extreme heat to increased irritability and aggression, which may help explain why tempers seem to flare on the hottest days. The practical takeaway is simple. If you're overheated, it may not be the best time to make an important decision, or tackle a difficult project, or even have a serious conversation. Cooling yourself down first could help you think more clearly, make better decisions, and avoid saying something or doing something that you'll later regret. And that is something you should know.

5:48What gives your life meaning? What gives it purpose? Those sound like enormous questions, but maybe they're more practical than you think. More people today than ever report feeling empty, disconnected, and as if their lives lack real purpose. So where does purpose and meaning come from? Can you create them? And what changes when you find them? Those are the questions my guest Arthur Brooks has spent years exploring. Arthur is a professor at Harvard Business School, a nationally syndicated columnist, and CBS News contributor. He's one of the world's leading voices on happiness and human flourishing.

6:28He wrote a huge best-selling book with Oprah Winfrey called Build the Life You Want, and his latest book is The Meaning of Your Life, Finding Purpose in an Age of Emptiness. This is one of those conversations that's going to stay with you long after it's over. It's insightful, practical, hopeful, and full of ideas that can really change how you think about your own life. Hey, Arthur, welcome to Something You Should Know. Hi, Mike. Great to be with you. Yeah, it's great to have you back. Well, I love this topic because, you know, I've always wanted to ask someone, and you're the perfect person to ask this of, what does it mean by meaning and purpose?

7:09When you talk about someone's life having meaning and purpose, what does that mean? Yeah, what's the meaning of meaning, right? Yeah, exactly. And there's a lot of things that we kind of know when they're missing, but we can't quite define them. I mean, most people can't quite really get their mind around air, but you're sure know when the oxygen is gone and meaning is kind of like that. Now, it is important if it is missing to figure out what it is. And so one of the things that I do, I've done in my work is to try to define it kind of precisely. The purpose question is, why am I doing what I'm doing?

7:46I mean, Mike is doing a podcast. Arthur is on the podcast. Why? You have to have an answer for why you're doing that. The reason that you're doing this podcast, you told me before we started, is because it's a great, great source of meaning in your life. I'm on this podcast because it's a great podcast and I want to talk about this important work to help people. Because my mission is to lift people up and bring them together in bonds of happiness and love using science. That's purpose. And people need to actually have an answer to that why question. So they have goals. They have direction. They can make progress.

8:20And last but not least is significance. That's the why does my life matter and to whom? Why does it matter? Why does it matter if I live or die? Why does it matter if I go to work? Why does it matter? And, you know, for me, the answer is because of my relationship with my kids and my wife and my family and my friends and God. And, you know, the why, the significance part is really the love question in our lives. And so that's the meaning of life. It's the coherence, purpose and significance of your life. And do you think there is one purpose? because it seems to me I could probably do a lot of things and be pretty happy.

8:54I'm doing this, but I could have probably done a lot of things. Yeah, for sure. I mean, there are a lot of different kinds of purposes. I've had different purposes in my life. They all have kind of a meta purpose behind them, however, I have to say. And so sometimes I'm podcasting and sometimes I'm on the road public lecturing. Sometimes I'm teaching my classes at Vanderbilt. I mean, that's different activities, but they all feed into the meta purpose of bringing more love and happiness to the world. That's sort of my big, big purpose. And the people who are happiest, their purpose is defined in a strong sense of mission.

9:30And so that's one of the things that I work with people who are really struggling is, okay, let's write a mission statement for your life. And by the way, that might change too, but that changes a lot less than your day-to-day activities. So if we asked 100 people, do you have meaning and purpose in your life? Is your life meaningful? What would the answers be statistically? So statistically, that's changed a lot, which is why I've done my work. Traditionally, if you're looking at young adults, which is a lot of what I've studied, traditionally about 85 % of young people would say, yes, yes, I have a strong sense of the meaning of my life.

10:07My life doesn't feel meaningless. And about 15 % would say, yeah, my life feels meaningless. And those are people generally who struggle with anxiety and depression, you know, mood disorders. And, you know, depression in particular has a lot to do with ruminative sadness and a sense of emptiness. It's really correlated with this, like, I don't know why things happen the way they do. I don't know why I'm doing what I'm doing, and my life feels really insignificant. That's really what it comes down to, and that's what you'd want to treat. But that number's really been creeping up, and it's been creeping up a lot, especially since 2008, since the introduction of the technologies that have really occupied our lives.

10:42And there's a reason for that. There's a science behind that. But the bottom line is that these days, about 30 % of young adults say, my life feels meaningless. And way more than that will say, my life feels less meaningful than it did in the past. I think that the best interpretation of the data is a majority of people under 35 would say that they've lost a sense of meaning in their life. It's much, much less, it's much less clear than it was in the past. You know, I wonder if that number is increasing, the number of young people who feel dissatisfied and meaningless and all, has something to do with, you often hear the criticism that younger people today feel like the world owes them something, that they don't have to go out and work for it, that it should be handed to them.

11:29I don't know if that's an accurate criticism, but you hear that. So I wonder, how does that play into this? You know, that's something that I've entertained an awful lot. And the truth of the matter is that all of the measures of narcissism among young adults have skyrocketed. They absolutely have. That comes from the work of Gene Twenge. You know, it's all about me. It's all about me. The world owes me everything. We have seen that. But fundamentally, I think actually there's a better explanation for both the narcissism and the sense of emptiness. And it has everything to do with the fact that we've started using our brains incorrectly.

12:06And that's pursuant to this massive use of pocket technology, of portable technology, of smartphones. It's literally changed the way that we use our brains in such a way that we're thinking about parts of life that are not related to meaning. We've vacated the parts of our brain that we need to actually understand the meaning of our lives. And give me an example of the parts that we vacated that we shouldn't have vacated. Well, the brain is divided into two hemispheres. This is a theory, a neuroscientific theory, very cutting edge, that comes from the work of Ian McGilchrist, a neuroscientist at Oxford, called hemispheric lateralization.

12:45Just a fancy way of saying the brain has two hemispheres and they do different things. The left hemisphere of the brain is the how to and what side that's based on information to solve problems that could be very hard problems, but you can solve them. So your car is a left hemispheric complicated problem. The right hemisphere of the brain is more about the why problems. It has more to do with meaning and intuition and mystery and love and happiness. The kinds of problems that are, they're complex, not complicated, meaning that they're pretty easy to understand, but they're impossible to solve because they're changing all the time.

13:21You just have to kind of live with them. So whereas your car is a complicated left hemisphere problem, you can figure out how what works, even if you don't know right now. Your marriage is a complex problem. It's a right hemispheric problem. I've been married 35 years, Mike, and I will never solve my marriage. You know, there's no formula for my marriage. I mean, it's like I've gotten better at it over the years, but, you know, I don't know next time we're going to have an argument because it's a living thing. That's the reason I love my marriage. Your cat is complex, which is why you love your cat.

13:53A A mechanical cat is complicated, which is why it's not a good substitute. And what's going on in our lives today is that we're getting a complicated simulation for the complex needs that we have in our life. We've got, you know, dating apps instead of in real life courting. We have social media, virtual friends instead of real friendship. We've got Zoom work instead of work in person. We've got the entertainment that kind of simulates real-life interactions going on all. It's kind of the matrix, actually. We're living in a simulation of real life, and it's leaving us empty because it's vacating the part of our brains that we need to be stimulating more, which is in-person, real-life, love.

14:36Even though there's been a lot of criticism about cell phone use, digital technology, and the things you just said, But the people are concerned about it. But it's not like we're going to give it up. It's here to stay. I don't see it going back the way it used to be. Well, I think it actually will, believe it or not. One of the things that we found over the history of technology, which is one of the things that I've studied as a social scientist over the years, is that we tend to misuse and overuse new technologies. And then we learn how to use them appropriately when they become tools. So things are at first entertainment and then their tools.

15:14When the telephone was first introduced, there was a belief that people would really literally stop going out of their houses, that they would have a guy in church holding up the phone and everybody would be in their living rooms just listening in. And nobody would see each other and they'd become kind of pallid and they'd become hermits, basically. And it would be horrible for society. It would be kind of the end of humanity. And, of course, that wasn't true. There have been people who have misused the telephone, and this is an even way, way more technologically advanced and intricate set of technologies that we're using today.

15:49But the truth is we're in the early stages of figuring out how to use it, so it's life-enhancing. Generally speaking, a new technology, it starts out substituting for real relationships, and then later on it complements those relationships. And that's what we ordinarily want. So I'm actually pretty optimistic. I see the problems and we're losing a generation. Don't get me wrong. I don't like it at all. But I do think that 10 years from now that most of the technology that's dividing people and isolating people today, we'll be using in a much healthier, much better way. Just because it's just an evolution.

16:26It just will happen slowly but surely. People figure it out. And when something is making people systematically unhappy, they don't put up with it for long. My kids use their phones less than they did five years ago. It's an amazing thing. You know, one of my kids, my oldest son is 28. He has his screen on black and white such that his dopamine receptors are less stimulated than they had been in the past. I have another son who has one phone for the weekend and another phone during the week. And the reason is because when he's home on the weekend with his family, he's 26. He's got two kids. He doesn't want his phone to be bothering him.

17:04He doesn't want to be attracted by it. My little girl who's 23, she's an officer in the Marine Corps, and she can't use her phone a lot of the time. It's illegal. So the result of it is that my kids have either voluntarily or involuntarily adopted more and more healthy habits. And the result is I've seen them become more social and happy over the years. I think a lot of people are rebelling. Well, I admire your optimism, but I don't see it. I want to see what I'm missing here when we come back in just a moment. A big thank you to today's sponsor, Vinted. I think most of us have what I call someday clothes.

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18:32Your closet looks better too. I mean, everybody wins, even the closet. So maybe it's time to stop waiting for someday. Download the Vinted app for free and start listing with no seller fees so you keep everything you earn.

18:51Pink Panther us here. Coach and Spotify are teaming up to bring music and style together, and they want you to be part of it. Grab your friends and head to the Tabby Tour, hitting cities around the country with live performances from special artists, exclusive experiences and personalized products and discover custom playlists on spotify book just for you based on who you are and how you listen live your story with coach learn more at coach.com my guest is arthur brooks he is one of the world's leading voices on happiness and human flourishing and he's the author of a new book called the meaning of your life finding purpose in an age of emptiness.

19:32So, Arthur, you said people are rebelling against the technology, but I don't really see it very much. I mean, I don't see any kind of movement towards let's get rid of it, but maybe I'm missing something. Yeah, well, you know, there are certain things that actually have worked. For example, now 28 states are banning cell phone use in the public schools, which is absolutely the case. That's the way it should be. And by the way, the fact that all states are not doing that is an example of real misunderstanding, even an abdication of responsibility by teachers, principals, school districts, superintendents.

20:09But we're finding that more and more and more that warriors on this and public advocates like Jonathan Haidt and Gene Twenge and, you know, these great social scientists and, you know, my own work is involved in this as well, is actually working in a lot of cases where kids are spending big parts of their day without the phones, some parts of the day as well. And that's actually resulting in higher levels of happiness and greater social connection for them. So, you know, there are things that we can do and that we are doing. If, in fact, all this digital technology use is the thing that's keeping people from finding meaning and purpose in their life, then by that argument, before this technology existed, seems like things would have been pretty good then.

20:53People were finding meaning and purpose until the cell phone showed up. Well, it was better, and I've got the data that showed that. It was traditionally about 15 % of young adults per year said, my life feels meaningless, and then it shot up after that. And that's the sort of thing you're looking for in a psychogenic epidemic, which just means an epidemic that creates something that creates great misery but doesn't have an obvious biological origin. After 2008 was when depression and anxiety really started to skyrocket as well. And there were lots of explanations. And there were all this baby boomers made too much inequality and hurt the environment or whatever.

21:29But the only realistic explanation for this is that was the major introduction of handheld technology is what was happening then. So was life better before? Well, not in every way. But when it came to meaning, absolutely. Life was better. And now life isn't as good. But it would seem that that paves the way to finding meaning. But by itself, in and of itself, you know, not using technology or using it in the right way doesn't give you meaning. No, it doesn't. What it does is it opens you up to finding it. Most people actually don't go on the grand quest for meaning. You know, they don't say, wow, now that I put my phone down, I'm going to the Himalayas to sit in the mouth of a cave and find a guru.

22:12I mean, most people don't do that. But you don't have to do that. As a matter of fact, you don't even have to be able to articulate the meaning of your life. You'll know it when you have it, just like you know it when you don't have it. But to do that, you actually have to be using your brain the way it was supposed to be used. It's very interesting. There's a lot of research by neuroscientists on something called the default mode network, which is a series of structures in the brain that turn on when you're not distracted by other stuff. It's when your mind wanders. It's when you have flights of fancy.

22:44It's where you think about kind of critical issues in your life. And it's when you're in the shower is when this happens to a lot of people. It's like, I don't know, man. I get my best ideas and I solve problems when I'm in the shower. That's because your phone isn't in there. And you're actually, when you're sitting under the hot water and your mind starts to wander, that's the right hemisphere of your brain turning on. When people are walking out in nature and they don't even think about looking at their phones, it's because the right hemisphere of their brain is turning on, or they listen to beautiful music, or they're sitting with their beloved and they're in a romantic sort of rhapsody.

23:20It's when they're, you know, when you're having a religious experience. I'm pretty tied to my phone, I have to say, but when I'm in church, I don't even think about my phone because I'm using my brain the way it's supposed to be used. And that's something that we can all do. Now, I'm not saying in every single one of those moments, the meaning of Arthur's life is X, Y, and Z, but my brain is working appropriately as such that the meaning of my life is finding me. Well, it sounds like what you're saying, or one way of saying what you're saying is that by getting away from digital technology and not letting it consume you, you are open to opportunities.

23:58You're open to finding things. I remember, I always felt my life was pretty meaningful and all that. And then I became a father and my God, how incredible was that? But, you know, I didn't know what I didn't know what I didn't know until I knew it. I know that's true. And that's actually a very funny thing about, I mean, that's a wonderful example because it's a wonderful thing. But there are examples of things that we don't want that nonetheless introduce us to it as well. The classic case is suffering. Suffering in life is largely a right hemispheric phenomenon. And this is one of the reasons that when I ask people, tell me when you most kind of found your sense of meaning in life.

24:41They never talk about that week at the beach in Ibiza. They certainly never talk about, you know, time spent surfing YouTube shorts. What they talk about is when somebody died or when they were afraid or they got sick or whatever it happened to be because suffering, which is something you don't go looking for, but it will find you. And when it does, if you don't try to eliminate it or distract yourself from it, when you actually go through it, you're going to find meaning in your life or meaning is going to find you. And whether you can articulate it or not, you're going to have a greater sense of it.

25:14So what do you say to the person who says, okay, let's say I really get my head out of my digital technology and now I'm open to finding purpose and meaning in my life. Do I just live my life and it will show up? Or are there things I can do to try to find it? Well, the first step really is, you know, getting away from the technology or at least putting it in its place. I'm not telling anybody to throw their phone in the ocean I do have a set of protocols in the book that are science-based and that will reorient your relationship toward it You know not using your phone in the first hour of the day not using your phone while you're eating Not looking at it in the last hour of the day not sleeping with it getting it out of schools very manageable stuff So most of the time you still have your phone, but it will reorient you and that's the first thing People used to live in a way that really invited a lot of meaning and they didn't know it, but they were exercising the right hemisphere of their brains.

26:11My great grandfather, Leroy Brooks, he was doing meaningful stuff all day long. Part of the reason is because he wasn't distracted by a cell phone. He was spending all day long looking at a mule's butt. You know, he was a farmer. His life was pretty boring moment to moment, but his life overall wasn't boring at all. And by the way, one side note of irony. When I talk to young people today, they're never bored for a single second because they've eradicated boredom with their phones, but their lives overall are grindingly boring. So if we just want to be not bored about our lives, this is a good thing to do.

26:45And what we need to do once we put the phone down for more times during the day is actually start thinking about doing things that once were ordinary and now are not. Things like, what am I actually doing to take risks with my relationship and my love life? What am I doing to express love toward and serving other people? What can I do to find my calling? What actually really calls to me in my work? Things like, how can I find more beauty? Life in the cell phone is not beautiful, Mike. I mean, a representation of El Capitan at Yosemite is not beautiful compared to El Capitan at Yosemite. And, you know, it's really important to find true beauty and opening ourselves up to even the hard parts of life, saying, you know, today is going to bring some wonderful things.

27:34I'm grateful for that, but it's also going to bring some hardships. Bring it on and living in this courageous way. This is how we invite meaning into our lives. Well, I really enjoy talking to you because you have this passion for making people's lives better. and you've got the evidence to support what you say and it's very compelling. Arthur Brooks has been my guest and his latest book is called The Meaning of Your Life, Finding Purpose in an Age of Emptiness. And there's a link to that book in the show notes. Great, Arthur. Always a pleasure. Thank you. Thank you. Really great interview. So succinct, so clear.

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29:01Why is it that smart people who know perfectly well what's healthy still eat things they know they shouldn't? It's easy to blame a lack of discipline, but according to my guest, that's the wrong explanation. Your brain and body are doing exactly what evolution programmed them to do. The problem is that evolution prepared us for a world where food was scarce, not one where calories are available 24 hours a day. Once you understand that, nutrition starts making a lot more sense. Daniel Lieberman is chair of the Department of Human Evolutionary Biology at Harvard and author of the book Fed Up, A Hungry Person's Guide to the Story and Science of Food and Diets.

29:47Daniel has spent decades studying how humans evolved, and he says that looking at food through the lens of evolution cuts through much of today's confusing nutrition advice. His insights may completely change the way you think about eating, exercise, and health. Hey Daniel, welcome to Something You Should Know. Thank you for having me. So what's your take on the fact that there is so much diet advice, so much nutrition advice, and yet people are heavier than ever. People are eating a lot of junk. So what's going on? Well, I think it's pretty clear that what we're doing ain't working. And I think there are many problems.

30:32But I think one of the most important problems is that we get really bad, confusing advice. And people have a hard time knowing what to do, even if they want to eat healthier and do better. And why do you think that is? Because the advice has certainly changed, and it still changes. low fat, high fat. I mean, so I think people throw their hands up and go, well, nobody knows what they're talking about. Well, exactly. I mean, that's, I think that's it. People are frustrated and confused. I mean, I mean, not just people. I mean, I am. That's one of the reasons I wrote the book. I mean, I teach anatomy and physiology at Harvard.

31:12I teach introductory courses on nutrition and digestion. And I look at the literature and I think, my God, what, you know, what am I supposed to do? How do I reconcile the fact that there are people who say I should be vegetarian versus the carnivore diets and the keto diets and the low-fat diets and the Mediterranean diet and the blue zone diet? I mean, even if you're an expert, the cacophony of ideas out there and contradictory opinions is really hard to, pardon the pun, but really hard to digest. And I wanted to set out and kind of explore the issue myself, partly from an evolutionary lens, because I'm an evolutionary biologist, but also integrating, you know, medical science and, you know, scientific literacy, you know, how should, how should we solve this really complicated problem of answering the question, what should I eat?

32:04Well, I've always thought that one of the fundamental questions in solving the problem you just outlined would be to go back and look at how people ate, how they evolved to eat, because there might lie a big clue. Well, yeah, I mean, that's the idea behind the paleo diet, but the paleo diet has its problems too. Remember that just because our ancestors ate something doesn't mean it's good for us, because natural selection, right? The idea is that if our Neanderthals or early modern humans ate it, we must be adapted to it. But remember that natural selection cares about reproduction, right? That's the only thing natural selection cares about.

32:45It cares about how much food you take in to turn into babies, and how many babies you can produce with that food. You know, it's food in, babies out is the basic equation of life. And so evolutionary theory isn't really all that useful a guide to trying to eat so that you don't get heart disease or Alzheimer's disease or cancer in your 60s, 70s, or 80s, because that's not what natural selection adapted us for. So even the conversation you and I are having right now, you know, what should I eat? That's a completely modern question. Until recently, nobody asked that question. If you're a hunter-gatherer, you don't like get up in the morning and you think, gee, you know, should I have gazelle today or kudu or should I have those berries or these plants or whatever?

33:28That's not what happens. You go out and look for food and you eat whatever it is you happen to find or hunt, right? And if you're a farmer, you know, farming started, what, about 600 generations ago at oldest. If you're a farmer, in the end of the day, when you're sitting down with your family, you don't pull out a menu, you eat what you grew, what you have stored. So this modern question that we have of trying to decide amidst this extraordinary abundance that we have is something that we were never evolved to do. Well, is that part of the problem? There's just too much to eat? Well, it is part of the problem, but it's also because I think we need to think about what it is we need to know.

34:07So our ancestors needed to know a lot in order to get their food, right? They needed to know how to hunt. They needed to know how to gather and process their foods. We don't need to know that anymore. You just go to the supermarket with a cart and load it up, right? Press a button. What we need to know today is a different set of skills. We need to know how to choose our food. And to do that, we need to have, everybody needs to have some basic knowledge about health and about nutrition and about digestion so we can make sense of all the crazy ideas out there that are often seriously conflicting.

34:39So here's to push back on what you just said. In the 60s and 70s, we had also an abundance of food, supermarkets full of food, people were not geniuses on nutrition, and we did not have the obesity and related health problems we have today. So something else changed. Well, I mean, heart disease was actually rising at the time. So after World War II, rates of heart disease started to increase substantially. So it's true that the obesity epidemic hadn't really picked up in the 60s. You know, when I was born, about 10 % of Americans were diagnosed with obesity. And now, of course, it's about 40 % or so.

35:22So you're quite right. Things have gotten a lot worse. But people were still getting sick, and they were getting cancer and various other diseases. But there's also, you're quite right, things have gotten worse. And the reason things have gotten worse is that the percentage of crap food that we're eating has gone up. You know, when your average person walks into a supermarket, they confront approximately, in the United States that is, they confront approximately 40 ,000 different products. Isn't that amazing? 40 ,000 products. And of those products, depending upon your supermarket and depending upon the classification, somewhere between 50 and 75 % of those products are ultra-processed.

36:06They've been manufactured in factories to make them appealing, convenient, inexpensive, although that's going up recently. But also, in order to do that, most of them have had their fiber removed. They've had sugar and fat added. A lot of the nutrients have been scoured out, and all kinds of chemicals whose effects we don't really understand have been added. So our food system has gotten considerably worse since the 1960s, absolutely. Another thing that really jumps out at me is the difference today versus 25 years ago of what makes a meal in terms of quantity, that meals are just bigger. Sizes of hamburgers are bigger, drinks are bigger, everything's bigger, and that that's considered a normal meal.

37:06Yeah, well, I mean, that's part of it. That's part of the industrial food system, right? We've managed to make food cheaper and more abundant and also more appealing. You know, if you like M &Ms, right? I have a friend who has a bowl of M &Ms in their office, right? And you know why all those M &Ms are colored differently? There's blue and red and green and all that kind of stuff. It's because our brains get excited by that diversity. We're more likely to eat more of them because, you know, now I have a red one, now I have a green one, now I have a blue one, right? So we've increased not just the quantity of unhealthy food, but also the quantity as well.

37:50A lot of the junk food that people eat, you know, my Achilles heel is like barbecue potato chips. I love barbecue potato chips. Okay, our ancestors didn't eat barbecued potato chips. And I wonder if the reason people tend to overeat some of these foods is they're not inherently satisfying. They don't push the right buttons that more natural foods from eons ago did for people that they would be more satisfied with what they ate. Those things don't register and we don't get satisfied, so we just keep eating and eating and eating. That might be true some of the time, but I think actually the manufacturers of your potato chips, and by the way, I too have, you put potato chips in front of me, not barbecue, but there's some other flavors I really like, and I have a hard time not eating more, right?

38:44And that's because these foods have been really engineered to hit what is actually called the bliss point. It's this perfect combination, because potato chips, think about what's in them. They're simple refined carbohydrates, which your tongue immediately basically turns into sugar. They're full of salt, and they're full of fat. And can you name a natural food that your ancestors ate that was rich in sugar, salt, and fat? no i can think of only one mother's milk milk is as a little as salty it's fatty and it's sweet and and you know that's the food that we started our life on right and it's the only natural food that is has has these three characteristics in abundance and and our brains just light up when we eat them and manufacturers know that food producers know that cooks know that right and So now we can create foods that, I mean, they've been tested on thousands of individuals.

39:47If you ever read this book by Michael Moss called Salt, Sugar, Fat, it's an extraordinary expose. He's a New York Times Pulitzer Prize winning investigative journalist. But he went and looked at the evidence for how big food companies manufactured, engineered, designed these foods so that you and I would keep reaching for more and more and more and more. They know exactly what they're doing, exactly how much salt to add to kind of just make our brains go haywire so that we just can't eat just a few of those potato chips. Well, remember, that was the Frito-Lay slogan, bet you can't eat just one.

40:25Exactly. Yeah. Yeah. Or Doritos. I mean, you put a bowl of Doritos in front of me, I'm helpless. Somehow I doubt it, but okay. No, I'm like everybody else. I mean, the way I control my food is by controlling what's available to me. But if you put a bowl of Doritos in front of me, I have just as much trouble as anybody else. And so what are we supposed to eat? Is there an answer to that question? Or it's not about what you eat, it's about how much you eat and when you eat. What's the answer? Well, I mean, unfortunately, there is no one answer. And if you're trying to lose weight, that's a whole other set of factors.

41:05and you know what diets help people lose weight the most? You know what's shown over and over and over again? The best kind of diet to lose weight. What? It's the diet you can stick with, right? So there are people out there who are absolutely convinced that a low-fat diet's the way to go and others who have shown evidence, randomized control studies, that people on low-carb diets lose more weight than low-fat diets, which, by the way, actually is true. but you know there but there's a big difference between effectiveness and efficacy so efficacy in medicine means how well something works in its ideal state right when you have like a randomized control trial you put people in a room and you give you know 12 people this diet you give another 12 people who have the same basic characteristics another diet and then you test for their effects right?

41:57And you control everything. And then you can measure the efficacy of diet A versus diet B. But in the real world, we don't necessarily eat what we're told. And we can't also remember what we eat. And we get cravings. And last night, I was standing in front of the refrigerator. Perhaps I indulged in some vanilla ice cream that was in the freezer. Anyway, we all have differences in terms of what we actually do, and that's effectiveness. And so we need to make an important distinction between diet's efficacy and diet's effectiveness. And what really matters for most of us is actually the effectiveness.

42:31But the general rules of nutrition, of like what the human body needs to function and stay healthy, do they vary that much from person to person? Not too much, no. What you need, though, isn't necessarily what's best for your long-term health, I mean, people can survive on a 100 % meat diet. The only food you actually need to eat, apart from some vitamins and minerals, is meat, is protein, right? Well, you don't need to get protein from meat. You can get protein from plants. But protein is the only nutrient you actually have to ingest. You could technically survive without eating carbohydrates, and you could technically survive without eating fats.

43:15But basically, you need protein. But if you ate a 100 % protein diet, you wouldn't do very well. But you could, you know, it's, it's, it's, it's, there is just no simple answer. I wish there were, but there isn't. That said, throughout the, you know, human history, different societies, different cultures have come up with, you know, reasonably sensible, healthy ways to feed people. And prior to the origins of industrial food processing, most of those diets worked pretty well. So the one diet that's been tested the most, for which there is the most evidence, is unquestionably the Mediterranean diet.

43:54There are probably now hundreds, maybe thousands of studies showing that the Mediterranean diet is generally associated with much lower rates of pretty much every major kind of disease you can think of. But fewer studies have been done on a traditional Asian diet or traditional Mesoamerican diet, traditional African diet. Most of these diets, though, share some basic characteristics. For one, they don't rely heavily on refined carbohydrates. I mean, we know that sugar is bad for us, right? And we also know, I think most people know, that white flour isn't as healthy as brown flour and that white rice isn't as healthy as brown rice.

44:29So making sure you eat foods that don't have a lot of added sugar and that they don't have a lot of refined carbohydrates is important. These diets are also supplement those carbohydrates with legumes. So, you know, in the Middle East, you have chickpeas or lentils or, you know, some other form of bean. In Asia, you supplement your rice with soy, like tofu. In Mesoamerica, you have corn and beans. I could go on, right? And then on top of that, You have some animal food, some dairy, maybe a little bit of meat or fish, some fruits, some nuts. Almost all these diets are based on the same kind of principles.

45:11And it's when, you know, they're not guaranteed. They're not optimal. They're not guaranteed to help you live to be 100. But people who generally eat these sort of traditional diets do pretty well. And we did pretty well on those diets until processed food kind of pushed us off them. And those diets, like the Mediterranean diet, has been studied and it does seem to be a healthy diet. But one of the side effects is people aren't real heavy either that eat that diet. Well, I mean, the two go hand in hand. I mean, obesity isn't the same thing as health, but they're related, absolutely. I mean, having obesity does increase your risk of a wide range of diseases.

46:01So yes, they're absolutely related. What about, there has always been this debate I've heard about, is a calorie a calorie? And if you want to lose weight, you just eat fewer calories or burn more of them. but then you hear, well, not all calories are the same. What's your take? Yeah, that's, I mean, that's a perfect example of how people get confused because obviously in one sense, a calorie is a calorie. A calorie is defined as the amount of energy that raises a milliliter of water, one degree Celsius. That's a calorie. So a calorie by definition has to be a calorie. But I think what people mean when they say that, I know what people mean when they say that is that the effects of calories on your body's metabolism differ based on the nature of the food that you're eating.

46:56So if you eat food with X number of calories that come from highly refined food that is full of sugar, for example, and there's no fiber, your body will handle those calories in a different way than if that food comes, you have to break that food down because there's fiber in it. So I've eaten an apple with fiber of X calories versus eating a fruit roll-up made from apple that has no fiber with the same number of calories. That fruit roll-up is going to cause me to store more fat because my blood sugar levels are going to go higher faster and my insulin levels are then going to respond more. And so that's what is meant by the phrase, a calorie is not a calorie.

47:45That in terms of your body's handling those calories, how your food is processed, what you eat with it, affects how your body responds to that food and how you store it and how you use it. So given all you've said about this, a person listening thinking, yeah, well, I get that, but what do I do? I mean, in a practical way, what is the information you've just given us? What do I do with it? And how do I move forward? The bottom line is that the most healthy diets that have been shown by good quality, high quality, repeated, randomized, controlled, gold standard studies are traditional diets that involve mostly unprocessed food, right?

48:32So food that is not highly refined. So brown bread over white bread and brown rice over white rice. And that is primarily plant-based, that has plenty of fruits and vegetables and nuts and seeds and not too much meat. And, you know, those are the kind of traditional diets that people did very well on for hundreds of thousands of years. And which, you know, they're not magic bullets. They're not going to solve all problems and ensure that you live to be 100. But they're certainly much healthier than a lot of the modern processed diets that people are eating today. And if you're trying to lose weight, yes, ultimately you need to cut calories.

49:19And the way to lose weight is primarily to figure out how to control the issue of hunger, not only when you're on the diet, but also after the diet. because one of the hard things about gaining weight is that it changes what's called your set point. And your body, once you're done with your diet, your body wants to bring you back to your previous weight. And so, unfortunately, like it or not, a diet is never temporary. A diet is permanent. And we need people to help them understand it and find ways to make their diets pleasurable and enjoyable and not onerous, but something that should be fun and pleasurable and enjoyable.

49:58Yeah, it just seems like eating shouldn't be so difficult. And as you've described, it doesn't really have to be if you understand some basic science about diet and nutrition. I've been talking to Daniel Lieberman. He's chair of the Department of Human Evolutionary Biology at Harvard. And his book is Fed Up. I love the title. Fed Up, A Hungry Person's Guide to the Story and Science of Food Diets. There's a link to that book in the show notes. Daniel, thanks for being here. Excellent. All right. Take care. Thanks so much.

50:35You ever worry that people can tell when you're nervous before a presentation, or that people know you're lying, or that you're embarrassed or unsure of yourself? Psychologists say you're probably overestimating how much other people can read you. It's called the illusion of transparency, Because you're acutely aware of what's going on inside your own mind, you assume those feelings are obvious to everyone else. In reality, most people are much worse at detecting your emotions than you think. That's good news if you have to give a speech or ask for a raise or do anything that makes you anxious.

51:13The butterflies you're feeling are probably a lot less visible than they feel. And that is something you should know. You know, in the summer, podcast listening dips a little bit because people are doing what they do in the summer. And so we could always use your help, if you have a moment, to share this podcast with someone, help us boost our audience back up for the summertime lull. I would really appreciate that. Just use the share button on the app you're using. I'm Mike Carruthers. Thanks for listening today to Something You Should Know. Pink Panther us here Coach and Spotify are teaming up to bring music and style together And they want you to be part of it Grab your friends and head to the Tabby Tour Hitting cities around the country with live performances from special artists Exclusive experiences and personalized products And discover custom playlists on Spotify Built just for you based on who you are and how you listen Live your story with Coach Learn more at coach.com

52:18Brussels clean up nicely at Sweetgreen. Maple glazed, roasted, and edges perfectly caramelized. Sweetgreen's fall harvest is back on the menu, and the season's most overlooked little green vegetable is dressed to be devoured. You know what to do. Order on the Sweetgreen app.