IRA FLATOW, host:
Up next, our national obsession with the bathroom scale. You know, there hasn't always been a bathroom scale. We're going to talk a bit about that a little bit more, and now why we're so obsessed with it. We are a nation of dieters, from Ornish to Atkins to Slim-Fast to Weight Watchers. We spend countless dollars each year on weight-loss products. You've got your books, your diets, your supplements, your gym memberships, your infomercial gadgets meant to shrink our abs, but you know what, we're still getting bigger.
According to the latest obesity researchers, 67 percent of Americans are overweight or obese. It seems almost like the harder we try to lose weight, the more weight we are gaining. And for all the money we spend on weight loss gimmicks, scientists at clinics and universities spend their research dollars trying to figure out even the most basic questions about weight. Is one diet better than another? Are there genetic reasons for obesity?
The answers have often been surprising, and my next guest has been following weight loss research, has gathered the myths and realities about dieting into her new book. Gina Kolata is a science writer for the New York Times. She's the author of "Rethinking Thin: The New Science of Weight Loss - and the Myths and Realities of Dieting." Good to see you again, Gina.
Ms. GINA KOLATA (Author, "Rethinking Thin: The New Science of Weight Loss - and the Myths and Realities of Dieting"): It's great to be here, Ira. It's good to see you, too.
FLATOW: What is the biggest myth about dieting?
Ms. KOLATA: It's that anybody who wants to can weigh - can be arbitrarily thin. They just have to push themselves away from the table, eat less and exercise more.
FLATOW: They just - that's what everybody says...
Ms. KOLATA: That's right.
FLATOW: ...if you only had more willpower.
Ms. KOLATA: Yeah. Right, of course. It's all up to you. You don't have to be fat. Anybody can be thin if they really wanted to. And it's a big myth.
FLATOW: And why is that a myth?
Ms. KOLATA: Well, there's been decade after decade after decade of research that explains not - that shows not just how very difficult it is, but why it's so very difficult. And then, there's even a more practical reason: if it was that easy, nobody would be fat.
(Soundbite of laughter)
FLATOW: So you're a - are you of the mind that it doesn't matter what you do, your body has a certain weight it wants to be and it's going to be that weight.
Ms. KOLATA: Well, I go - I tried - because I'm a reporter, I try to go into things with a blank mind, without a preconception.
Ms. KOLATA: But I think that the science has been very persuasive that there is not just one weight that you could be but a range of weights. It may span like 20 pounds or so. And if you try to go below it or above it, it becomes almost impossible, and that happens for normal weight people and for fatter people. Everybody - and it seems to be genetically determined.
For example, they did a study in the 1980s with children who were adopted and didn't know their biological parents at all. And the question was when they were 40 years old, how - what weight did they have? Did they resemble their biological parents or their adopted parents? They resembled - you probably guess - their biological parents. Same thing with twins, identical twins ended up not just the same kinds of weights, but even the same distribution of body fat. I have this slide from a journal like 30 years ago, where they have photos of twins, identical and fraternal. They even have like the same love handles and they were identical.
(Soundbite of laughter)
Ms. KOLATA: Identical.
FLATOW: You're listening to TALK OF THE NATION: SCIENCE FRIDAY. I'm Ira Flatow talking with Gina Kolata, author of "Rethinking Thin: The New Science of Weight Loss - and the Myths and Realities of Dieting." Our number 1-800-989-8255.
Is it a myth that now our kids are getting fatter and we've seen this happening, we - we hear about type 2 diabetes, all these diseases like that that kids never got before?
Ms. KOLATA: Well, actually, kids are fatter than they used to be. Everybody is slightly fatter than they used to be. But weirdly enough, the effect has really been on the fattest people getting a lot fatter and most people have gained on average like five or seven pounds which is probably, you know, getting towards - whatever the environmental effect is, it's probably - may be pushing people towards the top rather than the bottom or so their natural range.
Type 2 diabetes in kids is extraordinarily rare. It's so rare that it's almost impossible to track. It's much rarer than type 1 diabetes, which is very -which is a very rare disease. That's only one-tenth of all diabetics. But there are some children who have type 2 diabetes. And type 2 diabetes is affected by weight. The problem is almost everybody with type 2 diabetes would give anything not to have that disease. And if all they had to do was eat less and exercise more, most of them - who wants to inject yourself with insulin or take drugs all day?
FLATOW: But why are we seeing kids have it more or they - or did they always have it more and we never picked it up?
Ms. KOLATA: Well, it's not entirely clear because there's also a whole lot more surveillance especially when a fat kid comes in. And when you have a lot more surveillance, you're going to find a lot more because type 2 diabetes often has no symptoms. People don't know they have it until they have a blood sugar test.
FLATOW: Mm-hmm. I was surprised to read about how some of these new fad diets are really not new at all, especially the Atkins diet, which you reported.
Ms. KOLATA: Oh, that was amazing. Yeah, these - almost everything that people try to do with dieting was discovered a long time ago. The Atkins diet was discovered twice in the 1800s, both times, it was in best-selling books. The second one was by an undertaker, sort of a funny person to write the best-selling book on dieting.
FLATOW: He's going to see a lot of fat people.
Ms. KOLATA: Right. William Banting. He was very fat and he discovered a low-carbohydrate diet. He was so miserable. People made fun of him. And he could hardly walk and he had all these health problems. And then he got on this diet and lost weight, wrote a little pamphlet about it, became such a hit internationally that the word for dieting became banting. So people, instead of saying I'm dieting, they would say I'm banting.
Ms. KOLATA: And then that sort of fell out of favor in the early 1900s, when calorie counting came in and that's when our calorie charts were invented, and a lot of the same ones are there now. There's another best-selling book called "How To Live." And it told you, you know, you can't really - people think that they're counting calories, but you really have to count calories.
You throw some peanuts in your mouth between meals, that's calories. You put some cream in your coffee, that's calories. You can't fool your body. But if you actually kept track of your calories, you would be thin.
Ms. KOLATA: So we've had that one, too.
FLATOW: Mm-hmm. 1-800-989-8255. Let's get some calls in. Patrick in Tampa. Hi, Patrick.
PATRICK (Caller): Hi. So my question is if people are genetically predisposed to the weight that they are, then how can they - at least when I travel on vacation to Europe, it seems like all the Europeans are much thinner than Americans are.
Ms. KOLATA: I love that question because I was just in Europe. I was in Italy. And I hear this all the time. I actually asked one of the researchers. I said, are people - how much fatter are people in the U.S.? He said we really don't know because nobody but the U.S. does - has the kind of data we have. We have to - you actually have to weigh people, not just ask them what they weigh, and because people often, sort of, tend to, you know, shade the truth.
So I was in Italy, just out of curiosity, and I thought I'm going to try to guess who were the Americans. And I found that it was so strange, I couldn't tell what nationality people were until they - I heard them speaking.
And we were in this little town, we saw people at this bay, swimming, and my husband said, don't tell me Italians are thin ever again. And on a train, I saw this guy with this big stomach and I said, I know that guy is an American. Then I heard him speak - he was German.
So I don't know. I actually don't know. A lot of it is economics. You go to Europe. And when we were in Rome, we saw a lot of thin people. But then we were on a cycling trip and we were out in sort of rural Italy and it changed a lot. And if you're in New York, I think you see a lot thinner people than you do in certain other areas of the country.
PATRICK: Me, too.
Ms. KOLATA: So it's sort of hard to know sometimes.
FLATOW: We walk a lot here.
Ms. KOLATA: Well, that's the theory, but I'm not sure.
(Soundbite of laughter)
Ms. KOLATA: I need evidence. I'm a science reporter.
FLATOW: All right, Patrick. Thanks for calling.
PATRICK: All right. Thank you.
FLATOW: 1-800-989-8255. So is this just a moneymaking scheme, all these diets and losing weight? Or, what...
Ms. KOLATA: Oh, well, you know, I think there's more than - I think in a way, it's like the cosmetics industry that tells us, oh, if you just bought the skin cream, those wrinkles would go away. And you know you're buying a myth, but it's just so alluring. You see all the pictures.
On the other hand, there is this - I'd speak to a psychologist about why people keep going on diets. And he was really interesting. He said, you know - he asked the same question. He said, you would think that if in psychology there's one thing you learn is that behavior they call getting - gets extinguished.
If you get punished for it over and over again, you're not going to continue. So you go on a diet, you gain the weight back. You'd do another diet. You gain the weight back. Why would you go on another diet after that?
And he learned that people love going on diets. Sounds crazy, but they start out and they feel in total control. This is the beginning of the new me, the first day of the rest of my life. The weight starts to fall off at first and everybody tells them how great they look and they feel so wonderful and it'll never come back. They swear it'll never come back.
And then they get to a point where it does come back, it always, it almost - I can't say always, but almost always does. And instead of saying, well, I'm never going on a diet again, was that a bad experience, they say I failed -it was me. I just lost control one day and I could never get it back again, or I was under stress at work. And then the next diet comes along, and they're so excited. They're in control again. It's a weird cycle.
FLATOW: 1-800-989-8255 and there are scientists who believe just like you do, who have done research and believe that no matter what you do, you're going to be going up and down in this little range. Your body wants to be there.
Ms. KOLATA: Well, there have been so - this hasn't been just one study. There have been decades of studies, and they show over and over and over again exactly what you just said.
FLATOW: You point out, even people who've lost a hundred pounds.
Ms. KOLATA: Yes.
FLATOW: And you'd think I'm off. I've got the weight off. I'm going to keep it off now.
Ms. KOLATA: It comes back and they wanted - they were very interesting because they've lost - this is - among the first studies that were done. And they put people in the hospital, to get their weight down. And they found that they looked like they were a normal weight when they left the hospital, but biologically, they were like people who were starving to death - all their physiological signs and symptoms.
And then they craved food. Their metabolism slowed down by about 25 percent. So all of a sudden, they couldn't eat as much and the weight was - the weight came back.
I actually had somebody e-mail me. She says she's lost a hundred pounds several times and she's wondering if there's any hope for her with any diet.
Ms. KOLATA: I said to her that the research was not encouraging, but if she wanted to try again, who am I to say no.
FLATOW: There's some research that says these yoyo diets are dangerous for you. Not sure?
Ms. KOLATA: I'm not sure if it's dangerous for you, but you know, it's, it must be frustrating.
FLATOW: Mm-hmm. 1-800-989-8255. Tom is in Flagstaff. Hi, Tom.
TOM (Caller): Hi, how are you guys doing?
FLATOW: Hi there.
TOM: I saw this show on the Discovery Channel maybe a year ago about this very obese woman, who was in perfect health conditions beside she's obese. So I was wondering if the correlation between obesity and health is sort of a myth?
Ms. KOLATA: It's a great question. They're actually out - I have two kinds of answers. One of them was there was a big study in the U.S. that was - and it confirms with - also been shown on other countries as well, asking at what weight - what weight do you live longest?
What's the death rate at different weights? And it turned out that the healthiest weight to be at as far as mortality is concerned is the so-called overweight range. The mortality curve looks like a U that's sort of flat on the bottom, and the bottom of the U was overweight. And not just like people keep saying, slightly overweight - no, overweight. And at the very - at the other end sits the very thin and very fat - there's a higher death rate.
And very thin, people say, oh, that's because they were sick anyway. But no, they made sure that people who were in the very thin range had been thin for a long time, not suddenly. And they weren't - they took out the smokers, they adjusted - every time they look for something, the curve persisted.
So I said, well, why would it be that overweight is better? And one hypothesis -and it's just a hypothesis - is when people get old and they get a chronic disease and they get cancer or something, if they're very thin, they have no reserves, I mean, if they start to lose weight because they're ill, there's nothing left.
The other thing is the question of being fit and fat. There is - everybody is extremely concerned, as you know - as everybody knows about diabetes among fatter people. And many people who are fat have a sort of like a tipping point. They hit a certain weight range and then their blood sugar goes up, and if they could just get below it, it might go down again, but they have a lot of trouble.
There is a big study by the National Institutes of Health, which took people who were on the verge of getting diabetes, their blood sugar have been rising. And they divided them into three groups. One group took a blood sugar-lowering drug. One group was the control and one group dieted and exercised. They had intensive therapy on dieting and exercise.
At about seven years later, the diet and exercise group did better than any other group in terms of not getting diabetes. They hadn't really lost weight. What they'd done was kept up with the walking program. And that seem - and so that wasn't so much that they've lost a lot of weight, but that they were fit. So if maybe that if health is the issue, maybe trying to tell everybody that they have to lose 50, 60, 70 pounds - which they can't do anyway - is not really the best answer.
FLATOW: And the answer would be to get some exercise.
Ms. KOLATA: Well, this study seems to indicate that for diabetes.
Ms. KOLATA: Yes. And there's been studies showing that for heart disease, your heart - you'll do better with - well, these are - what they observe people. They are randomized to one thing or another. But observing people who do moderate exercise that seems to be good for your heart as well.
TOM: All right. Thank you guys. Have a good one.
FLATOW: Thank you. 1-800-989-8255. Let's go to Terence(ph) in Lansing, Michigan. Hi, Terence.
TERENCE (Caller): Hey, Ira. Love the show. Thanks for having me.
FLATOW: Thank you.
TERENCE: Hey, I just wanted to point out, you know, you talk about diets and I think diets really don't work as a short-term solution. But what about changing your diet? Recently, I've gone vegetarian and tried to go more vegan, almost. And I lost quite a bit of weight and I've managed to keep it off for about a year now. And I just wonder, you know, maybe the diets that the American people eat, the processed foods and all the foods that are heavy in high-fructose corn syrup and things like that maybe, you know, something - it leads to people being fat and not necessarily genetic.
Ms. KOLATA: That's a hypotheses that I've heard a lot. And the problem is there's lots of hypothesis about why people have been getting fatter, and there is nothing really solid that would sort of back any of them up. But it's interesting - your story is really interesting because - well, first of all, in my book, "Rethinking Thin," I did follow people in a federal study. And it went on for two years and I don't want to be disheartening, but the first year, they all lost a lot of weight and the second year, it came back again, which is kind of typical. Within five years, most people gain back weight.
However, there are people who don't and it's weird, it's unknown why some people respond to one thing and some people respond to another. Some people respond very well to some of the diet drugs that are on the market, which for most people do very little of, if anything at all. But some people actually really respond. There's something that just hits them.
I was at a dinner last night. There's a woman there who's been on the - went on the Atkins type diet about 10 years ago and lost a lot of weight, and she's been eating that way ever since and never put it back. And now, you've gone on a vegan. type diet, lost some weight and haven't put it back. So there may be - and it's totally unnoticed, and this is like a total speculation on my part - various things that might work for somebody, and maybe not for the group as a whole. And if something works, I mean, I would say go for it, of course.
FLATOW: Mm-hmm. Thanks for calling. 1-800-989-8255. You've studied a lot of research. You looked at a lot of stuff. You're a great science writer. Did you discover holes in research? You say why didn't somebody - why don't they look at this or what is missing. You know, you say this is anecdotal information about that.
Ms. KOLATA: Well, I wish that we - you know, actually, what I discovered was that there's research that is ignored. As though holes that have been filled and no one wants to hear about the filling, so they pretend it hasn't happened. My favorite one was two gigantic federal studies asking about whether you could prevent children from gaining weight. And they both - they were randomized, controlled clinical trials of the most rigorous kind. And both of them, they took hundreds of schools and they randomly assigned them to be an intervention school or a control school.
And the intervention school, they did everything they say you should do for children. They took - they got rid of all the junk food. They gave them lots of nutrition education. They taught the children what to eat. They brought the parents in and educated the parents. They got all the families involved. They had physical education. In fact, they had lots of it. They hired special teachers to come in during the day and give them phys-ed breaks. Everything.
Two years later - and one group was done with mainly kids in the Southwest who are often - lots of Native American kids who are at high risk. Usually if something works, you'll see it in the high-risk group right away. The other was just kids who were just normal-risk in another whole group, another giant study. So each study lasted two years and the question was did the intervention kids gain less weight? And the answer was no effect whatsoever.
So one of the studies, this time with the Southwest kids - I went to the journal and they always say this study has been cited. Then they say what journal cited it. It was cited nowhere. No one ever cited that study. And called the researcher, he said, oh, yes, you're very astute, my friend. No one ever mentioned it again.
Ms. KOLATA: It's like they don't want to hear it. And then I asked people, well, okay. So what does this mean? It tells you that everything you're trying hasn't had an effect. I mean, not that you would say eat junk food. But to say that's going to make you thin rather than healthy, to change your diet, maybe we should rethink it. And they said, oh, no. We just have to do more. Get everything involved. The whole entire community has to change. The grocery stores have to change. I asked a statistician what he thought of this and he said it reminds him of a story...
FLATOW: Hey, let me just interrupt you.
Ms. KOLATA: Okay.
FLATOW: Because I have to give a station break. We're talking about dieting this hour on TALK OF THE NATION: SCIENCE FRIDAY from NPR News with Gina Kolata, author of "Rethinking Thin" and telling a great story that I had interrupt about...
Ms. KOLATA: Sorry.
FLATOW: No. No. No. This is a great story because I have never heard the study myself either.
Ms. KOLATA: No one had. No one. It's an amazing study.
FLATOW: And you heard the study where they've tried everything with these kids.
Ms. KOLATA: Two studies.
FLATOW: Two studies. And nothing worked.
Ms. KOLATA: Nothing worked.
FLATOW: And you went back to the researcher and he said you're the first person asking about it.
Ms. KOLATA: That's what it was. It was amazing.
FLATOW: And continue.
Ms. KOLATA: Well, I asked a statistician.
Ms. KOLATA: I said is this amazing or what? Here are these two studies, millions and millions. And one of them cost $20 million - gigantic studies -and nobody ever - even the government, that did it, never talks about it. And then when I asked them what to do, they say just get everybody - obviously, it wasn't enough. You have to do more.
FLATOW: Of course.
Ms. KOLATA: He said it reminds him of a study - it was a study that was done in the 1800s where a guy really believed that if you bleed people with leeches, it would cure tuberculosis or something - pneumonia - to cure pneumonia. So he did a study, a nice rigorous study, and the leeches didn't help. So his answer was you have to bleed harder and bleed longer.
FLATOW: Things haven't changed.
Ms. KOLATA: Yes, like the leeches.
FLATOW: Wow. Wow.
Ms. KOLATA: I mean, maybe doing more would help but you got to show that. You can't assume.
FLATOW: But we have all our - all our policies are based on these kinds...
Ms. KOLATA: I know. They are all based on it.
FLATOW: They were all based on if we just do the right thing and...
Ms. KOLATA: Right. Right.
FLATOW: ...then you're saying, doesn't matter what you do.
Ms. KOLATA: It didn't matter.
FLATOW: It's going to - it's not going.
Ms. KOLATA: Well, there is something in the environment that made people get fatter now than they used to be. Now, we're also healthier than we used to be. Every major disease is on the wane. People are getting them later. Disabilities are down. People are living longer. People are definitely healthier than they used to be.
One researcher at the Centers for Disease Control told me that he was at this photography exhibit with some colleagues. And they saw this picture of these kids, they were coal miners around the early 1900s. And his colleagues looked at them and said, look, they are thin. He said, damn right, they're thin. But you think they are healthy? These are kinds in the coal mines. The first thing they looked at it and they say, look at that, the kids are thin. I mean, there is more to health than being thin.
FLATOW: All right, we're going to take a break. Come back to talk more with Gina Kolata, author of "Rethinking Thin: The New Science of Weight Loss - and the Myths and Realities of Dieting." Boy, we've busted a couple of myths today. I learned something new. I think you did. Stay with us, we'll be right back after this short break.
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FLATOW: I'm Ira Flatow. This is TALK OF THE NATION: SCIENCE FRIDAY from NPR News.
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FLATOW: You're listening to TALK OF THE NATION: SCIENCE FRIDAY. I'm Ira Flatow. We're talking this hour about weight loss with my guest, Gina Kolata, senior writer for the New York Times, author of "Rethinking Thin: The New Science of Weight Loss - and the Myths and Realities of Dieting." Our number, 1-800-989-8255.
Did you come up with any of your own hypotheses about being fat and whatever, about why all this may be - we may be seeing, you know, fatter kids and is there something going on out there?
Ms. KOLATA: Well, the main thing that I've discovered was how little is actually known. Because you could say, well, it's the environment. Then, what in the environment and when does it affect you? One thing that kind of surprised me was so many people now - and more and more, like everyday, I keep hearing about researchers who say we think now that the place to look may be back in prenatal life, which was kind of a surprise. And they said, you know, we know that animals, that if you make changes in the diet or all sorts of things during prenatal life, their offspring grow fat as adults. And weirdly enough, there's also a couple of examples with people. There've been 15 studies now that showed that women who smoked during pregnancy had kids who tended to grow fat as adults, which is weird. No one knows why.
And then, there's also, with animals, if you don't give them enough to eat during pregnancy, their kids tend - kids - their offspring tend to develop diabetes and get fat. And no one knows why again. But with people, there is this one sort of a grisly experiment. During World War II, in Holland, there is this - they call it the hongerwinter, where everybody was starving - pregnant women, everybody - wasn't getting enough to eat. And when the babies were born, they looked fine at birth and they looked perfectly normal as they were growing up. But now, in middle age, they're getting - they are fat and they're getting diabetes.
Ms. KOLATA: So it's weird. I mean, it's so - people know that you can make a difference in lots of health things, including weight and diabetes by affecting various things in the environment that early on. So there...
FLATOW: When you're in the womb?
Ms. KOLATA: In the womb, yeah.
FLATOW: We know that with alcohol, certainly, right?
Ms. KOLATA: Yeah. Right. Yeah. So here, if you say the environment made us fat, you say, well, when and what? If you start from the womb and you go all the way on from there, what's happening and when is it happening? It's just not clear.
FLATOW: Wrong choice of word - a fertile ground for study?
Ms. KOLATA: Well, there's a lot of study.
FLATOW: Yeah. About that.
Ms. KOLATA: A lot of study. And especially in this in-the-womb stuff.
Ms. KOLATA: Every time I look at my e-mail, seems like somebody else is doing an in-the-womb study, usually with animals, but they're all trying to sort of get at what could it be. Is there something that we didn't think about, some little trigger, because what many people are beginning to think is that once you start - once you've already got this little range that your body wants to be in, it's very hard to budge it. And they did discover in mice, though, that there is - a couple of critical times, one of them is in adolescence, when the brain sort of gets rewired.
Ms. KOLATA: And you may change it then. So maybe it's an environment thing in adolescence. Who knows? It's really a mystery.
FLATOW: So it may not just be a genetic thing is what you say.
Ms. KOLATA: Well, it probably isn't genetic, because genes didn't change that much. On the other hand, genes and environment interact.
Ms. KOLATA: And in the Civil War, the average height of a man was 5 feet 5. So genes didn't change, environment did. And our environment has changed but we have no - no one knows. We - I'm not a scientist. Scientists don't know what -they have lots of ideas, but they don't really know what did it.
FLATOW: Is there some are you yourself would like to, you know, as a journalist, pursue? Would this be a good...
Ms. KOLATA: What I like to see - I just sit there and react.
FLATOW: Well, if we have - you mentioned that you have this idea about the prenatal stage.
Ms. KOLATA: Oh, no. I'm really fascinated with that.
Ms. KOLATA: I would also love to see whether or not there really is kind of an Achilles heel to this - that's a horrible - that's like the wrong analogy. But if there's like a little weak link in this brain system that controls weight because - so there's two ideas about whether or not there'll ever be a magic pill to sort of let people lose weight. One of them is that this system is so tightly controlled with controls upon controls that if you knock one thing out, something else will take its place.
So it may be almost impossible to ever really affect it, because it's so important for survival. You know, people don't - aren't supposed to starve to death or eat themselves to death.
The other is that if you were clever enough and you knocked out a few things at once, maybe you could tweak the system and control and then, sort of, lower the bodyweight range that people have.
FLATOW: Right. I want to thank you for taking time to be with us. A fascinating book - "Rethinking Thin: The New Science of Weight Loss - and the Myths and Realities of Dieting." Gina Kolata, always a pleasure.
Ms. KOLATA: Thank you. It's great being here again, Ira.
FLATOW: Thank you. Good luck with the book.
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