NEAL CONAN, host:
This is TALK OF THE NATION. I'm Neal Conan in Washington.
If you've ever wandered through the food court at the local mall, you've been assaulted by the smells of cinnamon buns, french fries and chicken strips, and you may have felt appalled that felt almost evolutionary and it's zeal.
Well, there's a reason for that. Inside your 21st-century flesh - a caveman, a hunter-gatherer yearns to burst out and club a vending machine. As a result, the Americans are getting heavier and heavier. But don't blame Colonel Sanders, blame Charles Darwin.
In a new book, Deirdre Barrett points out that KFC or McDonald's would be happy to sell us tofu burgers and carrot strips, but our inner hunter-gatherer wants fat, and sugar, and salt - cravings that made sense for almost all of human existence, just accepting those past few thousand years. And we would all be in great shape, she argues, if we could just replicate the hunter-gatherer lifestyle.
Later in the hour, Supreme Court decisions, including Bong Hits 4 Jesus, and the $54 million pants suit.
But first, evolution diet and exercise. Do you find that your goals and your instincts are in conflict? Does your brain whisper salad when your stomach yells steak and ice cream? Our number is 800-989-8255, 800-989-TALK. E-mail us, email@example.com. Our e-mail address, firstname.lastname@example.org. You can also join the conversation on our blog, npr.org/blogofthenation.
Deirdre Barrett is an assistant professor of psychology at Harvard Medical School, where she teaches in the behavioral medicine program. Her book is called "Waistland: The Evolutionary Science Behind Our Weight and Fitness Crisis." She joins us from our studios of member station WGBH in Boston. Nice to have you on the program today.
Professor DEIRDRE BARRETT (Assistant Professor, Psychology, Harvard Medical School; Author, "Waistland: A (R)evolutionary View of Our Weight and Fitness Crisis"): Hi, nice to be here.
CONAN: And I guess, the first thing you have to do is, well, erase some of the stain that we associate with hunter-gatherer who - they may have been in great shape but only because we think, well, life was hard and they we're starving to death.
Prof. BARRETT: Well, yes. I mean, throughout all of evolution - I mean, even pre-human evolution - our primate ancestors were hunter-gatherers. And it was 10,000 years ago that agriculture even began, and just about 1,000 years ago for many societies. So there's been no time to evolve toward eating the kinds of things that we're eating now. Our instincts are still for the foods on the Savannah.
CONAN: Mm-hmm. You've, in fact, even come up with an evolutionary explanation for our fondness for plastic flamingos.
Prof. BARRETT: Yes. Yeah, one of the small points of the book is that not only our food and exercise habits, which are the most out of whack, but even where we like to be is basically instincts developed for the Savannah. So flat, beautiful, lush grass with the right kind of birds, which turns out to look a lot like the lawn flamingos, and our, you know, our 72-degree temperature behind our air-conditioned glass is what we like to sit around looking at.
CONAN: But should we really emulate hunter-gatherers? I mean, if - you know, this was a pretty tough way to make a living.
Prof. BARRETT: No, it wasn't actually. That's such a myth of the caveman always on the verge of starving, spending their entire day searching for foods, really. If you look at what anthropologists know about the ancient hunter-gatherers - except for some dramatic ice age, as in periods of famine - on average, they seem to have wandered around, spending maybe three hours of their day gathering what they needed, have plenty of time to be playing with their children and relaxing.
But they were getting vigorous exercise for few hours a day and they were gathering high-fiber, high-nutrition kinds of foods. Even some of the current hunter-gatherer societies live a relatively healthy lifestyle if they're not pushed off to lands where there's almost no food left. So it was actually when agriculture began that the average lifespan dropped, that a lot of the diseases of modern man appeared, and that we began working long, long hours to feed ourselves.
CONAN: Which raises the question, if farming was such a, you know, a detriment to human evolution, why are we still hunter-gatherers?
Prof. BARRETT: Well, because what makes a habit survive is not whether it is pleasant and feels good to the average individual, it's whatever produces the most offspring. And you can feed more people on smaller amounts of land with agriculture. So the people who practiced farming actually died a little younger, but they hit puberty a bit sooner, they crank out more children and they populate the land more, and they reproduce. And hunter-gatherers reproduce in more not as numbers, even though these are healthier children and the people are living longer. So, agriculture is good for promoting itself, but it's not really good for the individual.
CONAN: Yes, some people have argued that agriculture is a pretty good for that particular strain of wheat or rice or whatever - maybe not so good for the people raising it?
Prof. BARRETT: Yes, yes, exactly. It propagates itself, but it's not so good for human beings.
CONAN: In terms obviously, you say that there's a sort of, you know, synchronistic mismatch between what we actually look to - find to eat because of the way we were raised as hunter-gatherers. This sends us cues that are a little bit askew in 21st-century America.
Prof. BARRETT: Yes. I mean, the advice about listen to your body or trust your instincts, just unfortunately is not true in our modern setting. You can only completely listen to your instinct if you were back in the primal kind of setting. We need to listen to our intellects these days. That's what we have big brains for is to give us some flexibility over instincts.
CONAN: So when my instinct might say that - to have lunch at the Godiva shop and you're suggesting I listen to my brain instead.
Prof. BARRETT: Yeah. I mean, our instincts say look for fat, look for sugar, look for salt, because those are necessary in small amounts and they used to be rare. And we just have not had time to evolve to, you know, look for fiber, look for green vegetables, look for the vitamins that have now gotten rare.
Prof. BARRETT: So instincts are telling us very wrong things in our current food environment.
CONAN: So back on the Savannah when we were hunter-gatherers, the leafy vegetables, hey, you didn't have to have evolutionary imperative to go eat those things as they were around. Evolution demanded that you go looking for that rare piece of fat.
Prof. BARRETT: Mm-hmm. Yeah. So the bad news from all this is that we can't just listen to our bodies, and that very moderate changes such as are often advocated just won't do it. But the good news is that radical changes are often easier biologically. That the metabolism of your insulin and glucose is such that if you really stop eating refined foods, large amounts of unnatural fats, and lots and lots of carbohydrates and sugar, that it's really the first couple of days when your body is just screaming for those things because it's used to it.
And then all kinds of glucose and insulin metabolism adjust, hormones like ghrelin and leptin adjust, and after a few days, it gets much easier. And many people think that if they, you know, can't go two days without their favorite cookies, they couldn't possibly go two years. But that's actually not the case. It gets easier.
CONAN: It gets easier - so you say. 800-989-8255, 800-989-TALK. E-mail us, email@example.com. Our guest is Deirdre Barrett. Her new book is "Waistland." And let's see if we can get a caller on the line. This is Whitney(ph), Whitney is with us from, Buffalo, New York.
WHITNEY (Caller): Hi. It's interesting because I tend to be somebody who, in most of my life, has always listened to my brain and tried to eat fiber and healthy foods and less meat. But when I was pregnant a couple of years ago, I found this very visceral like primal need for meat, and I don't know if it was iron or the protein. But whatever it was, it was like the first time in my life I really felt like I had to listen to my body.
CONAN: Hmm. Would she have been wise to do so, do you think, Deirdre Barrett?
Prof. BARRETT: Well, I would say that extend one's appetite shift somewhat with pregnancy, it is in the direction of things that you need, and that message that a little more meat or at least a little more protein is probably needed, is probably true. Now, through pregnancy, you well may still, like the rest of the time, have instincts driving you to overeat a bit.
And then that piece of it is probably not a good idea to gain lots, lots more weight than is necessary to support the pregnancy. But to shift diets somewhat seems to be instinctually naturally something that we do for the baby to develop properly.
WHITNEY: Yeah. It really felt like a biological need. And actually, my body took care of me pretty well. I didn't gain excessively and I do have that beautiful baby. But…
CONAN: Well, congratulations on the beautiful baby, Whitney.
WHITNEY: Thank you.
CONAN: Appreciate the phone call.
CONAN: Bye-bye. Let's see if we can go now to - this is Cristina(ph). Cristina's with us from Buffalo, New York, also.
CRISTINA (Caller): Hello.
CONAN: Hi there.
CRISTINA: Hi. I just wanted to make a comment. I grew up, you know, eating the traditional American diet. You know, my mother was an excellent cook and we always had fresh vegetables, so I don't know how traditional it really was, but I kind of grew up with a well-rounded diet. But over the past few years, I've just noticed that I wasn't feeling well, I was tired a lot, and my cycles were getting really painful.
And so I - that was going to start juicing, and I started juicing fresh vegetables at home, and eating salads and just doing all the things that I know I should be doing, and noticed a huge change. And what I've also found is that it seems to me that even someone like me who eats very well at this point, turns to have - still have those cravings for ice cream and a cheeseburger now and then. And I think it usually happens when my body is lacking really what it needs.
And I have to wonder if - it's kind of like which came first, the chicken or the egg. You know, I'm wondering to myself, is there places like KFC and Burger King (unintelligible) require because people want it or are people wanting it because that's what their body is accustomed to. I mean, if you eat sugar every day, you're going to want more and more sugar. And I, myself, came to the point where when I think about a salad, my mouth starts to water.
CONAN: Deirdre Barrett, you raised this chicken and egg problem very early in your book.
CRISTINA: I'm sorry?
Prof. BARRETT: Yeah. And that's a very good question about which causes which. The answer is basically both, that it's a vicious cycle, that our bodies absolutely are programmed to crave fat and sugar and salt and some of these things that get concentrated into our fast foods. So it really is there as an instinct in the first place that we always need to be fighting to a certain extent. But the more you eat of some of those things, the more the hormone shift and adjust to crave and expect those things.
And then just habit wise, the less you look to salads and healthier things for your pleasure in eating. So it goes both directions. We have some natural craving for it, which is why Western-style fast food is so insidiously spreading around the globe and taking over some healthier styles of eating. But also, then the more you eat of it, the more you crave it.
CONAN: Cristina, thanks very much for the call.
CRISTINA: Thank you.
CONAN: We'll be back with more. We've been talking about diet for the most part. Let's not forget exercise. We'll get to that when we return.
I'm Neal Conan. It's TALK OF THE NATION from NPR News.
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CONAN: This is TALK OF THE NATION. I'm Neal Conan in Washington.
In her new book, "Waistland," Deirdre Barrett argues it's not fast food chains that make us eat unhealthy foods, it's evolution. We crave sugars and salt and fats, she says, because for thousands of years, these were difficult to find. Her solution: eat like humans did 10,000 years ago. We'll talk more about what that means in a moment.
Deirdre Barrett is an assistant professor of psychology at Harvard Medical School. The full title of her Book is "Waistland: The Revolutionary Science Behind our Weight and Fitness Crisis." When it comes to food, do you find your goals and your instincts are in conflict? 800-989-8255. E-mail firstname.lastname@example.org. You can share your stories on our blog at npr.org/blogofthenation.
And Deirdre Barrett, just returning to that previous call, our caller said that after a while, she came to understand that eating better made her feel so much better and the same thing goes for exercise. You point out in the book that after people institute a program of regular exercise, they understand they feel better. Why isn't it our instinct to do something that makes us feel better, eat well and exercise?
Prof. BARRETT: Because, again, our instincts are geared toward our hunter-gatherer existence thousands of years ago. And we used to get plenty of exercise in the course of hunting, and finding water supplies, and finding campsites. We were automatically moving around. And often, if anything, there was an incentive to rest when you didn't need to be moving around that much. So our modern environment is just as out of whack in its exercise demands as it is in the food supply.
And so again, we need to use our intellect to remind ourselves that exercise is good for us. And it's somewhat reinforcing once you really start doing it. But just like with changing your diet, it's that very initial effort where you're going against your habits that feels the most difficult. And once you establish new exercise habits, it's somewhat self-reinforcing.
CONAN: And you say this is not a moment for modest change. You go - you think that some of the goals that has been set out in some of these exercise programs, a half an hour, three times a week, they're too low.
Prof. BARRETT: Well, especially some of the sort of expectations that you're going to loose a lot of weight, or get yourself very healthy by some like slow moderate walking a few times a week. I mean, our ancestors and our bodies are really geared to be moving around several hours out of the day and doing some bursts of really intense exercise. And you don't want to start too intensely and injure yourself.
But really, most people should be doing some pretty vigorous exercise. And in "Waistland," I described three strategies that I think are best for different people. A lot of - especially by baby boomer age - a lot of people who really were athletic have gotten completely out of the habit. And if you use to have some sport that you loved, I think going back to it or going back to a similar sport that may be a bit easier to do once you're not so young, is the ideal way for somebody that ever connected with athletics.
But if not, to join a gym, just more in the way you take your vitamins, you know, to get yourself to an exercise class or someone who's going to talk you through it, or a trainer who's going to take you around on the machines. Or thirdly, just to think more creatively about making your jobs something where you can be moving instead of sitting at a desk to - you are not going to work to make more…
CONAN: We're not talking about becoming a first ranger necessarily, but using your…
Prof. BARRETT: No. No, just in almost any office job, you could be out walking briskly, talking on your cell phone, or walking briskly as a way of having your half hour meeting with a colleague, rather than, you know, feet propped up on the desk, having the same conversation.
If you have a relatively unskilled job, like, you know, behind the counter at a cash register in a convenient store, you could just as easily be behind the cash register at the garden supply shop, which will have you hopping up to go pole bags of soil around, as well as wringing them up. Almost any sort of job has some equivalent that you could do more moving around in.
CONAN: Let's get some more callers on the line. This is Tom. Tom's with us from Cider Rapids.
TOM (Caller): Hello.
CONAN: Hi, Tom. Go ahead, please.
TOM: Oh, It's a kind of topic that I'm sort of been interested in because - and I never heard anybody discuss this. But the Atkins diet works because of these evolutionary things that basically, we're kind of like bears. We - when the fruit is available, and the sugar is - was a really hard thing to get hold of, you just gorge. And I can eat two pounds of cherries or strawberries at a sitting, no problem.
But - and your body is geared up to store that as fat. But how do you know when it's time to burn it? It's - in some places, it's the winter, in some places, there's the dry season, and Atkins says, you know, just - when there's no carbohydrates in your system, your body says, oh, it's the bad time. It's time to burn fat. And then, you know, and the fast food joints cheat because they put sugar in with fat.
And you started to keep eating, but your body's sort of programmed just kind of like bears in the summertime, with the fruits there - we eat as much as we can, we store it away. But it's never winter in our modern world, and I just kind of wonder what she thought about that.
CONAN: Well, I have to say Deirdre Barrett makes a point of not coming up with a diet of her own and says, in fact, most diet plans are pretty good in that they talk about eat better, eat less and exercise more. Do I have that right, basically, Deirdre Barrett?
Prof. BARRETT: Yes. I mean, I advocate, really, any of the major diets would work rather well if we just followed them. I actually agree with the caller in a sense that I think that our biggest deviation from our natural diet is lots and lots more refined carbohydrates. And that is part of why Atkins tends to promote weight loss.
I don't entirely like everything about Atkins in terms of how much saturated fats he would allow and sort of equating cheeseburgers and fish as fairly similar on that diet, when I think one is much healthier for other reasons. But I agree with most of the caller's…
TOM: Can I (unintelligible)?
Prof. BARRETT: …what the caller said. I think that most diets work by getting us back closer to our natural intended diet, even if they're not explicitly saying that.
CONAN: Tom, you were trying to say something?
TOM: Well, the thing is when I done Atkins, it works. You don't have to. You don't have to exercise or nothing. The fact is there's a trigger in our bodies that if there - if you have little or no carbohydrates in your system, your body just turns on the fat burner.
TOM: It's amazing and…
CONAN: I think.
TOM: Excruciatingly boring and - Atkins never pretended it was a balanced diet. He chose you to take, like, three or ten multiple vitamins a day.
CONAN: Right. Tom, I'm not - I don't think Deirdre Barrett was saying that Atkins didn't work, she said it might have some long-term health problems, but…
TOM: Well, I think she might make a point, but the reason it works is because of this natural mechanism. But it's really hard to do. But I think - what I found is that I can't eat that much fat.
TOM: I just don't like it. I mean you eat - the fact is once you got that fat machine burn - going, and it's burning and as long as I don't slurp up and eat a Twinkie, and then it takes you two days or three days to get it going again, is that you just don't eat that much fat.
CONAN: All right. Tom, thanks very much for the call.
Prof. BARRETT: Yeah. I largely agree. It's just when you say you don't have to exercise, you don't absolutely have to for weight loss, but you do for the best health improvements. And in "Waistland," I am trying to tell people how to get ideally healthy, not just how to drop weight, although, that's a big piece of what's wrong with it for most people.
CONAN: And Anne(ph) joins us on the line. Anne is with us from Mountain View in California.
ANNE (Caller): Yes. This is a great conversation. I have two observations and I was hoping your guest could comment on them. When I went on vacation to visit relatives in a, say, more remote part of our country, the fresh fruits and vegetables were pretty manufactured-looking. I mean, I almost felt like they should have to call them something else besides tomatoes and vegetables because they look pallid, they look unnatural looking and they're produced to this sort of manufactured agricultural process.
ANNE: And, you know, not to be a snub about that, what was really interesting was that I found that when we were there, I was constantly craving more food. Even when I was stuffed to the gills, I was craving more food. And we took a trip to an organic food store about an hour away, brought a whole bunch of fresh fruits and veggies and canned foods.
And when I turned to eating those, I finally felt full, eating normal quantities, and I wonder if some of that, like, you know, we are what we may be our fruits and vegetables are, what they eat. Maybe we had been taking a too simplistic look at what's in some of the, you know, some of the nutritional content of some of these foods…
CONAN: Well, it's interesting.
ANNE: …aren't grown with more natural soils. And if they can comment, I wanted to make…
CONAN: Can we do one at a time?
ANNE: Oh, okay.
CONAN: All right. Deirdre Barrett, one of the things you write about in the book is how we talk about refined foods, we think about removing the wholes from various grains when they're - before they're made into whatever they're made into - excuse me, bread, or pasta, or whatever. But you also point out that this refining process as you describe it happens, starts a long time before the foods are even coming off the trees or off the hoof.
Prof. BARRETT: Yeah. I mean, even some of the foods that we think of as natural, like corns, say, was bred from a grain with little bitty seeds into this thing that is mostly starchy, high-carbohydrate and relatively little of the original nutrition or fiber, so that even aside from what we call refining, we're eating some pretty bland refined foods. And furthermore, these are what we subsidize. Right now, we have crop subsidies to grow corn. We don't subsidize broccoli.
It's just completely backwards in terms of what we should be doing to get ourselves to eating better. But I think the caller's description of those diets and the effects makes two important points. One is we tend to crave diversity because that instinctually gets us more different nutrients and so it is good to be eating little bits of a variety of vegetables. But also, fiber fills you up more and when you're eating more refined things, you can stuff an awful lot more into yourself before your signals will tell you that you're full.
CONAN: And your second point, Anne?
ANNE: Well there's - the point about the internal microorganism balance is different now than it was a hundred years ago or everywhere evolving. And I sometimes, you know, microorganisms in us eat what we eat and different microorganisms have different preferences. And I've wondered sometimes if some of the cravings that we have in our diets are the result of having an imbalanced microorganism population.
I mean, for example, I have wondered sometimes if the French have stayed thinner not as much because of drinking wine or whatever, but because the French cheeses are alive and they have microorganisms that are, you know, hundreds of years old and have been consumed, you know, that were gotten from the national environment and…
CONAN: Deirdre Barrett is there anything to the bugs-in-the-gut theory?
Prof. BARRETT: Well, yes, although they tend to work in the same direction as some of our own enzymes and hormone levels, which is that they - once it digests milk do arrive with milk if it's not homogenized; if it's yogurt or something, once it digest protein, arrive with protein. So we get gut bacteria going that corresponds to what we've been eating. And it is a kind of vicious cycle self-perpetuating. If we're eating mainly the simple carbohydrates, then we have things that only break that down and give us a stomachache if we lots and lots of fiber for the first time once. But they really do adjust.
So if you get through a few days - if your stomach doesn't feel quite as good when you're eating the new diet, it will all settle out after a little while. Like I say, just like our own hormones adjust.
CONAN: Anne, thanks very much for the call.
CONAN: Deirdre Barrett's book is "Waistland: The (R)Evolutionary Science Behind Our Weight and Fitness Crisis." You're listening to TALK OF THE NATION from NPR News.
And here's an e-mail from Alison in the Bay Area of California. Here in Berkeley, where we're blessed with flavorful fresh food everywhere, I've grown accustomed to eating food that's cooked as little as possible. Now, I've developed an aversion to cook food as though it were pre-chewed or otherwise, processed. My question is, did early humans need to crave cooked food because there were additional health benefits to that chemical process or is eating raw the original plan?
Prof. BARRETT: Well, eating most things raw is certainly what most of our ancestors did through most of evolution. I mean, again, it really goes back pre-human to what our primate ancestors were doing. Humans started cooking much earlier than they started farming, and it seems to be many meats that were much more digestible if cooked. So probably, there are a few foods where it either breaks down cellulose in some of the tougher vegetables or kills bacteria in meats where it may be preferable, but most foods have more nutrition if they're eaten raw and that is closer to what was going on through most of evolution.
CONAN: Let's get Jeff on the line. Jeff's with us from Mayfair, Arizona.
JEFF (Caller): Yeah, hi. I just wanted to ask your guest. I don't have any theory on why this has worked for me, but I tried vegetarianism for about five or six years, but I have a very physical job. I work as an ironworker and I'm building swimming pools in Arizona so I got a lot of exercise. And it seem like when I did that, I really did lose my strength, lost weight, it probably wasn't good weight. I'm 41 years old.
Now I've, kind of, got a mixed diet where I'm still eating occasional cheeseburger, you know, eating a steak now and then, but basically cut out the junk food. I mean, terms like, fries or ice cream or candy or anything, you know, sodas, things like that. And it seems to really work. I mean, my weight's really good. I'm feeling a lot better. So I, kind of, wanted to know what she thought about vegetarianism versus meat eating in a situation like that.
CONAN: You know, high-exercise situation. What do you think Deirdre?
Prof. BARRETT: Yeah, I mean, I think that certainly naturally humans were omnivorous, which did include some animal protein in the diet and that there are vegetarian diets that can get enough protein into the diet, but it's certainly easier when eating meat. The main thing wrong with the quote, "cheeseburgers" is the refined bread bun and the amount of fat that's in them for the amount of meat and shifting to something like more fish in the diet might be really ideal, but…
JEFF: Yeah, actually I've been eating the wheat bun, the wheat bun at Fatburger.
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Prof. BARRETT: Yeah, I think the buns are as bad as the burgers. But lean beef is certainly somewhat close to what our ancestors were eating, and we developed for. And fish, for various reasons, seems to be the very healthiest protein.
CONAN: All right, Jeff. Thanks very much for the call. And I wonder, Deirdre Barrett, how much do you live like a Paleolithic woman?
Prof. BARRETT: Well, I actually eat fish and shellfish myself and not red meats as a way of keeping the fat content of my diet down. I am one of those people I mentioned who did not ever love exercise as a young person. So I belong to a gym and I definitely do it in a, sort of, take-your-vitamins way, and envy the people that have some, you know, real athletic…
CONAN: Little castor oil there every morning, yeah.
Prof. BARRETT: …inclination. And I feel like the grocery stores we have these says do allow us to be hunter-gatherers, you know, wandering through the aisles, picking up sprouts and berries and all of the things that really couple of generations back, we couldn't, and in certain parts of the world, one can't. But it's very easy as a middle class person in America to eat just about like hunter-gatherers did. And it's actually more difficult, but not impossible, I think, in some of the other parts of the world and economic situations.
CONAN: So devolution, that's the secret.
Prof. BARRETT: Yes.
CONAN: Thanks very much, Deirdre Barrett, appreciate your time today.
Prof. BARRETT: Thank you.
CONAN: Deirdre Barrett's book is "Waistland: The Evolutionary Science Behind Our Weight and Fitness Crisis." And she joined us today from the studios of our member station in Boston WGBH.
Coming up, the Supreme Court rules on Bong Hits 4 Jesus, plus the case of the $54 million pants comes to an end. Stay with us. It's the TALK OF THE NATION. I'm Neal Conan in Washington.
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