120. 100 Ways to Fight Obesity

Freakonomics asks a dozen smart people for their best ideas. Get ready for a fat tax, a sugar ban, and a calorie-chomping tapeworm.

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:01Stephen J. Dubner?

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• 0:46Stephen J. Dubner?

  Which begs the question, why not apply it to other aspects of life? Like banking, for example. Well, PNC Bank did, since its inception, proving time and again that the best banking strategy isn't the exciting type, but the steady, reliable, definitely not YOLO type. PNC Bank: Brilliantly Boring Since 1865. Brilliantly Boring Since 1865 is a registered mark of the PNC Financial Services Group, Inc. PNC Bank, National Association, Member FDIC. Freakonomics Radio is sponsored by Hotels.com. Hotels.com helps you find and book the right stay for work faster.

• 1:27Stephen J. Dubner?

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• 2:11Stephen J. Dubner?

  time, you stay in control. Put ChatGPT to work on your most ambitious ideas and projects. Get started at chatgpt.com by selecting Work Mode, available on Plus and Pro plans.

• 2:33Stephen J. Dubner?

  Steve Levitt is my Freakonomics friend and co-author. He stands about 5'11", weighs 160 pounds, so he does not have a weight problem. But he has been thinking about our collective weight problem, but not thinking about it in a way that most people think about it. In fact, not even close.

• 2:54Speaker 01

  What we've learned over time, which is one of the most surprising things about obesity, is that the body has a very strong homeostasis device, which makes it both hard to gain weight and hard to lose weight. So the calculation I did was a simple one. I eat probably 2,800 calories a day, and I like eating. So let's just say I decided I wanted to go up to 3,300 calories a day, an extra 500 calories a day, and I want to do that for the rest of my life. Now, you might think, well, if you did that, that I would, my weight would essentially go to infinity, that that extra 500 calories would pile up and pile up and pile up.

• 3:34Speaker 01

  And the rough rule of thumb people use is that every, maybe 3,500 calories turns into a pound. And so you would think, you know, my god, you're going to gain a pound a week for the rest of your life. It turns out I wouldn't, that because of the way the body works, I would only gain 40 pounds. So if I started this when I was a little younger, when I was 20, then I could have basically, instead of being 160 pounds my whole life, I could have been 200 pounds my whole life, and I could have had an extra 8.7 million calories over the course of my life. Now, the experts agree that if I weighed 200 pounds instead of 160 at my height, it might cost me a year or two of life expectancy. And when you do all the multiplication and the value of life calculations, it turns

• 4:17Speaker 01

  out that roughly every extra 1,000 calories I consume shorten my life enough that I would pay about a dollar. And that's the price. So it turns out that every extra coke that I drink is about 15 cents in shortened life.

• 4:36Stephen J. Dubner?

  Today on Freakonomics Radio, things you did not know about obesity and what to do about it.

• 4:52Speaker 02

  From WNYC and APM, American Public Media, this is Freakonomics Radio, the podcast that explores the hidden side of everything. Here's your host, Stephen Dubner.

• 5:12Stephen J. Dubner?

  On today's episode, we are talking about obesity. Now, obesity is a problem that is at once terrible and wonderful. Wonderful because it represents our ability to produce delicious, safe, affordable food for billions of people, something that not so long ago, doomsayers were saying was not possible. And it's a terrible problem because, well, collectively, we eat too much of that delicious, affordable food, much of which, in fact, is not at all good for us.

• 5:47Stephen J. Dubner?

  Chris Economos, who studies obesity and childhood nutrition at Tufts University, says that more than 1 in 3 children and adolescents in the US are overweight or obese.

• 6:00Speaker 03

  The obesity rates for children have tripled in the United States over the last 40 years, and there are dramatic health and societal consequences that result from that. Some are immediate and some are long-term, particularly because childhood obesity leads to adult obesity.

• 6:14Stephen J. Dubner?

  And persuade me one step further that adult obesity, in addition to being uncomfortable and, you know, unappealing for a lot of people for a lot of reasons, talk about the actual dangers of that in terms of morbidity, mortality, social costs, so on.

• 6:32Speaker 03

  Sure. 66% of adults in the US are overweight and obese, and the health consequences are enormous. And they include the development of type 2 diabetes, orthopedic problems, cardiovascular disease, a shorter lifespan, lost productivity, and there are serious social consequences as well. There's isolation, mental health issues that develop as a result of first minor and then major depression. So it really is catastrophic when you put it together.

• 7:02Stephen J. Dubner?

  Catastrophic and expensive, too. Obesity-related healthcare makes up roughly 20% of our total healthcare spending, which in turn represents nearly 20% of our GDP. So there are all kinds of reasons, financial, political, moral reasons, to address obesity. And there are all kinds of ideas, too. Today, we wanted to bring you some different ideas. Steve Levitt, whom you heard from earlier, tends to have a lot of different ideas. He's an economist at the University of Chicago. He also started a consulting firm called The Greatest Good, which takes on regular consulting business, but also, once in a while, gets hired by a philanthropist or a foundation

• 7:46Stephen J. Dubner?

  to tackle a problem like obesity. That's what happened recently. The Robert Wood Johnson Foundation, whose mission is to, quote, "improve the health and healthcare of all Americans," asked The Greatest Good to put together a one-day think tank on childhood obesity. So we gathered up about a dozen people, nutrition experts and academics, some other interested folks, for a brainstorm. We should say here that the viewpoints that you'll hear do not necessarily reflect the opinion of the Robert Wood Johnson Foundation.

• 8:22Speaker 04

  I'm Mary Story. I'm at the School of Public Health at the University of Minnesota.

• 8:26Speaker 05

  I'm Daniel Kahneman. I'm a psychologist. I know essentially nothing about this particular topic.

• 8:32Speaker 06

  I'm Peter Attia. I'm a co-founder and running nonprofit organization in San Diego called Nutrition Science Initiative. I'm Jim Marks. I'm senior vice president of the foundation. Steve Kortmaker. I'm at Harvard School of Public Health.

• 8:43Speaker 07

  Jeff Canada at Harlem Children's Zone. Brian Mulaney, co-founder of Smile Train. And I'm Kelly Brownell from Yale, and I run a place called the Rudd Center for Food Policy and Obesity.

• 8:53Speaker 03

  Good morning. I'm Chris Economos. I'm at the Friedan School of Nutrition at Tufts University.

• 8:58Speaker 08

  I'm Eric Oliver. I'm a political scientist at the University of Chicago. I guess I'm here as a skeptic.

• 9:04Speaker 09

  I'm Bill Dietz. Until June, I was the director of the Division of Nutrition, Physical Activity, and Obesity at the Centers for Disease Control, and now I'm an active citizen.

• 9:13Speaker 10

  I'm David Laibson from Harvard. I'm a behavioral economist. My specialty is self-regulation and behavior change, getting people to save more.

• 9:24Stephen J. Dubner?

  We met down in Princeton at the Foundation's headquarters. I moderated the discussion. The only rule was that no idea was off limits, no matter how absurd or politically incorrect or repugnant it might seem. This podcast is meant to give you a seat at the table. We begin with a question that Steve Levitt asked the group. The answer, as you'll hear, shows just how insidious the obesity problem is. Is there anyone in this room who thinks that, that under the age of one, we have a problem with nutrition for babies?

• 10:01Speaker 11

  Probably. Yes.

• 10:03Speaker 06

  And I would go one step further, Steve. I would say in utero, we have some pretty good evidence to suggest that maternal diabetes, and I don't even mean frank diabetes, I mean hyperglucose, hyperinsulinemia during the critical period of development of fetal pancreas plays an enormous role in obesity because there's only like, I think it's about a six-week window where the fetus pancreas is developing. If that pancreas develops in a high glucose environment versus a low glucose environment, it develops more beta cells. So all of a sudden, a child is now born more predisposed, they're not born insulin resistant, but now they're more predisposed to being insulin resistant. And then when you look at, you know, I do this, it drives my wife bananas. When I'm in the grocery store, I get so angry, I take photos of baby food.

• 10:45Speaker 06

  I turn it over and I'm like, interesting that baby formula number one, ingredient number one, high fructose corn syrup, ingredient number two, modified cornstarch, ingredient three, hydrolyzed. And it's like, well, gee, that's interesting.

• 11:02Stephen J. Dubner?

  That was Peter Attia. He used to be a surgeon, now he runs a nonprofit called the Nutrition Science Initiative. His hypothesis is that of all the contributing factors to obesity, by far the greatest may be the prevalence of sugar in the modern diet, sugar in all its many, many forms. Now, some of these sugars are disguised, a lot of carbohydrates like bread and pasta, for instance, which most people don't think of as sugary at all, and some couldn't be any more obvious, like soda. Over the past few decades, the average American kid doubled his intake of soda. Overall, he eats and drinks about 180 more calories a day, which is at least a 10% increase, although lately the data seem to show that increase has plateaued.

• 11:47Stephen J. Dubner?

  Now, most of these extra calories come from snacks. So, say what you will about how kids are less active today than they used to be, how screen time has risen, the fact is that calories drive weight, especially the calories that don't have any nutrition attached to them, which, by the way, tend to be the cheapest calories. So, given all the empty extra calories that kids are consuming, we probably shouldn't be too surprised that a third of them are obese. I'm curious whether anybody knows about children's awareness of obesity as an issue among themselves and how recent that is and what the magnitude is?

• 12:29Speaker 03

  I mean, I know a little bit. We just had a paper accepted, it's in press. It was a national survey of children, asking them, "What do you think about obesity? How aware are you about it? What do you think happens when a child is overweight and obese?" And it's all about not fun to be a heavy kid, stigmatized, isolation, bullying, all the things you'd expect. Pretty high awareness. When you stratify by kids who selfclassify as being overweight, they worry about everything more, not only being overweight, but their grades, getting in a car accident, not having money.

• 13:03Speaker 07

  Yeah, and the way this plays out is that kids even that are a small degree of overweight or a body that doesn't look like everybody else's are the subject of incredible teasing and bullying. I mean, the heartbreaking stories are just amazing. So, I think Steve's right. I think all of these things are significant costs to society and to the individuals as well. And I would perceive it as two lines that cross, that in childhood, the social costs are way higher than the medical costs. Then that changes over time, and then the medical costs would go in the opposite direction, that they would be less significant in childhood and greater as age grows older, so these lines would cross. Now, it doesn't mean that the stigma's not important to adults.

• 13:45Speaker 07

  The wage penalties, marriage penalties, all these sort of things are very significant to people, but as a child, it's especially extreme.

• 13:52Speaker 10

  I want to play, and just to twist to that, which is... I think kids are very, very aware of weight, obesity, and there's all of that social stigma. But what I think they don't perhaps have the sophistication of a 35-year-old adult is an understanding, the mapping from what they're eating to how, over the next four or five years, they're going to become obese, and how their exercise also maps into that. And so, even if they think obesity is terrible, "I don't want to be heavy, my peers who are obese are getting teased," they still need to understand how millions of actions translate into that outcome.

• 14:33Speaker 10

  And that is subtle, and I think it's particularly problematic because of the delay between the action and the outcome. We know that organisms learn, humans, other animals learn really well when you do something, and instantly you get feedback that's clear, and learn terribly when, you know, we can talk about lots of animal studies where if the feedback comes four minutes later, the animal never learns.

• 14:56Speaker 08

  David, can I push you on that question? Because one thing that you said that struck me is that you said that children need to be, I'm sorry if I'm misquoting, but I think that children need to be able to sort of see the consequences of their behaviors, and then the way a 35-year-old adult could. And I think part of the difficulty with obesity, at least as it's been framed, is that 35-year-olds still do a very good job relative to sort of their own sort of decision-making framework. So I'm wondering if that's even a reasonable standard to hold up with respected kids in terms of their own capacity for, you know, making decisions that we might want them to make.

• 15:28Speaker 10

  I completely endorse that. It's hard for a 35-year-old adult, and it's worse for the eight-year-old kid.

• 15:34Speaker 05

  I just want to reinforce David's implied point. I saw the meeting in terms of behavioral change as how do you change parental behavior?

• 15:47Speaker 05

  Changing child behavior, forget it. Parental behavior is going to be very difficult.

• 15:54Speaker 03

  I just wanted to insert something just a little bit different to think about. I just finished a study on new immigrants. And, you know, many of them arrive here from an environment where food is limited, it's highly ritualized, there's no snacking. And you watch them navigate this obesogenic environment in a short amount of time and you see obesity manifest very quickly. And the, one of the underlying things that we're looking at carefully is time trade-offs and time use, which leads to behaviors that cause obesity. And so as we think about this problem, I'm not an expert on time trade-offs, but there's a whole literature on it and we're studying it. And I think it's important because it leads people directly to the foods that we're describing and the overconsumption that results.

• 16:38Speaker 03

  So I don't know how to factor it in, but I think it's extremely important to watch it unfold in a short amount of time is fascinating. It's basically what many of us experience over decades.

• 16:54Stephen J. Dubner?

  That was, in order of appearance, Chris Economos, Kelly Brownell, David Labson, Eric Oliver, and Daniel Kahneman.

• 17:04Stephen J. Dubner?

  Jeffrey Canada runs a nonprofit in New York City called Harlem Children's Zone. In the beginning, it focused on education and drug prevention, but over time, Canada says, obesity became a big deal.

• 17:19Speaker 12

  Well, you know, it started out being a small aspect of our work until we realized that about 40% of our kids are obese. It is a huge epidemic in our community. And so while we're preparing kids for college, we want these kids to become productive members of society. You know, one of the things that happens in a place like Harlem is that it's almost like a black hole of taxes. All of the tax dollars come in. We're paying for prisons and jails and reform schools and emergency visits to the hospital and special education services. And so few folk are... are able to work and work long periods of time that you don't get folks actually contributing back to society.

• 18:03Speaker 12

  If my kids who are going to college, which they will, all end up getting sick in their 30s and 40s, and their healthcare costs simply skyrocket. Again, we've not solved that equation. So we felt that it was very much part of our job to not just get these kids in college, but to get them in college healthy so they can come out and have full productive lives, and we can really make sure that they can contribute to society.

• 18:31Stephen J. Dubner?

  Fighting obesity, Jeff Canada told the group, is in some ways harder than fighting drugs or school dropouts.

• 18:40Speaker 12

  I mean, we got into this because of the morbidity and mortality issues 10 years ago. Just looking at what was happening in Harlem, and you could see the end result of people in wheelchairs, missing legs and feet and stuff like that. And, you know, this is a horror show, what's causing it, and it all traced backwards to this issue of what's happening with young people. But it's become, I think, for me, a lot more complicated because some of this is, I think, based on what parents and kids do. But I believe a huge percentage of this is based on what commerce does in certain communities. And, you know, I once, I made the statement, and I still believe that, I never thought

• 19:25Speaker 12

  I was going to get rid of drugs in Harlem. I just wanted drugs to be sold in Harlem the way they're sold in the suburbs, right? Quietly, anonymously, that it's not pervasive, like this is the way of life and this is the main commerce of this community. I feel the same way about a lot of what's happening in the inner cities. It is almost impossible to get healthy things, and it is very easy to get all of these unhealthy things. And so even as we're thinking about kids and adults and families, I'm worried that as the market has depended on these communities to consume more and more of these unhealthy foods and beverages, we're up against more than just a parental sort of concern because

• 20:08Speaker 12

  of all of the commercials, the advertising, the accessibility. And so all of that, to me, suggests that some communities are more vulnerable than others, even if you could sort of deal with lots of the challenges that families and individuals have. So that's one issue. I have become increasingly convinced, and I am no scientist, that a lot of this is addictive behavior, that the sugar that folks consume, it is an instant feedback, eating a Twinkie. I don't know, maybe I'm the only one that gets that sort of satisfaction from doing it. But lots of families, I think, are using food, right? Because the rest of their lives are so horrible that this is something they actually,

• 20:51Speaker 12

  you know, you can enjoy, and now Jeff wants to take that from you, too.

• 21:06Stephen J. Dubner?

  Coming up on Freakonomics Radio, some palatable and not-so-palatable ideas to fight childhood obesity.

• 21:15Speaker 10

  Imagine a world where I could consume a parasite that could not reproduce, and it would go into my bloodstream, and it would basically make the things that I eat ineffective as nutrients, and they would flush out of my body.

• 21:40Stephen J. Dubner?

  Freakonomics Radio is sponsored by Southern New Hampshire University. The best investments are the ones you make in yourself, and no one knows that better than Southern New Hampshire University. With more than 200 online degree programs, no set class times, and low online tuition, Southern New Hampshire University is built to fit your life today and set you up for success tomorrow. Education is an investment. Why not make it a smart one? Apply for free at SNHU.edu/freakonomics.

• 22:13Stephen J. Dubner?

  Freakonomics Radio is sponsored by PNC Bank. Boring, great word, bad rep. Yet, time and time again, here at Freakonomics, we find that when something culture-changing happens, boring things like calculations and careful planning are usually behind it. Which begs the question, why not apply it to other aspects of life? Like banking, for example? Well, PNC... Bank did since its inception, proving time and again that the best banking strategy isn't the exciting type, but the steady, reliable, definitely not YOLO type. PNC Bank, brilliantly boring since 1865. Brilliantly boring since 1865 is a registered mark of the PNC Financial Services Group, Inc.

• 22:53Stephen J. Dubner?

  PNC Bank, National Association, Member FDIC. Freakonomics Radio is sponsored by Amica. You know what they say, if you want to go fast, go alone. If you want to go far, go together. So go with Amica and get coverage from a mutual insurer that's built for their customers, one that looks after what's important to you together. Auto, home, life, and more, coverage that fits your unique needs. Amica helps you protect what matters most. Visit amica.com and get a quote today.

• 23:33Speaker 02

  From WNYC and APM, American Public Media, this is Freakonomics Radio. Here's your host, Stephen Dubner.

• 23:46Stephen J. Dubner?

  Steve Levitt and I recently spent a half day running a brainstorming session for the Robert Wood Johnson Foundation on the topic of childhood obesity. One of the only ground rules was that no idea was considered beneath discussion. Did you know, for instance, that quitting smoking, which is plainly good for your health, usually leads to a significant weight gain? So the good news is that the American smoking rate has fallen from 45% in the 1950s to about 24%. But the bad news, well, here's Bill Dietz, the former CDC official.

• 24:22Speaker 09

  The estimates are that the reduction in tobacco use accounts for maybe 20% of existing obesity. Right. So, you know, we get little and kids. Very little and kids.

• 24:35Stephen J. Dubner?

  Okay, so no one is going to push for, say, putting cigarette machines in schools to fight obesity. But we did want to hear any other ideas from our participants, so we started a lightning round. Should we put pressure on? All right, what do you got?

• 24:51Speaker 04

  In grocery stores, unhealthy foods would have to be restricted to certain locations, such as the back of the store.

• 24:58Stephen J. Dubner?

  Oh, like the porno department in the video store idea.

• 25:05Speaker 06

  Abolish sucrose and high fructose corn. So don't even forget about taxing them. Just pretend they don't. Take them off the face of the earth.

• 25:11Speaker 13

  Right now, businesses can write off all the money they spend marketing to kids as a business expense. Just eliminate that tax deduction.

• 25:18Speaker 12

  I would say, start a real public health campaign aimed at the big food companies where we should be talking about how many people have been killed by Cokes and Pepsis and whatever, and just make it so that they feel the pressure to reform their practice.

• 25:37Speaker 14

  Like a list of shame?

• 25:38Speaker 12

  Just a big shame, just a big national shame thing with all the big companies on it.

• 25:43Speaker 07

  We talked about doing that. Well, in the spirit of completely impractical things, I would want to get rid of marketing of any product to any human being.

• 25:52Stephen J. Dubner?

  No, I can see that's viable, yeah.

• 25:54Speaker 07

  No, what I would do would be to sequester it out there somewhere so people could voluntarily go find it.

• 25:59Stephen J. Dubner?

  So it's all opt-in marketing?

• 26:01Speaker 07

  It's opt-in marketing, and so billboards and TV commercials and stuff would be forbidden because it just seems to me that marketing does have some benefits, obviously for the companies. But to the individual, it has a small number of benefits, but a huge number of downsides. And of course, food, we get caught up in this in a positive way, but that's what I would do.

• 26:21Stephen J. Dubner?

  Thanks. Chris?

• 26:22Speaker 03

  So I'm going to focus on parenting and the schools. So the first one is to hold our educational system accountable to deliver nutrition, physical activity, and media literacy by requiring standardized tests to assess it. Set a baseline, measure the baseline, set some benchmarks, and move the entire system along and treat it as important as some other things. And the second is to change the home environment by incentivizing parents through health insurance, work site, or welfare benefits to make a commitment to healthy parenting.

• 26:57Speaker 08

  Great. Eric? I think we need to have a, or suggestion that we have a paradigm shift and embrace a paradigm shift and really let go of obesity as a target of health remediation and just focus everything on malnutrition. Seems most of our discussion here is really about childhood nutrition. Obesity has a lot of cultural baggage associated with it. I think it's an imprecise marker, even though it's an available marker. And with Michelle Obama's campaign, I'm afraid that childhood obesity has become politicized in a partisan way now. And that makes it a more difficult kind of issue to focus on. And I just wonder if we would do better by making this an issue of malnutrition.

• 27:42Speaker 01

  Wait, wait, let me tweak this. So I think, I think the word malnutrition actually doesn't work very well because malnutrition implies hunger. But, but whenever you say like metabolic- Syndrome. No, but you have a bigger one than that. What is it? Metabolic derangement. Derangement, yeah. It seems to be- It's not going to be a bumper sticker, is it? Well, no, I don't know. Stop metabolic derangement. But I like, I like the idea of putting together what you, what you two are both saying, which is that if you, you could get a fresh start, if you had the right marketing behind the idea that there's a package of horrendous disease states which you're heading

• 28:24Speaker 01

  towards. And actually, the mar, like, marketing around metabolic syndrome doesn't do it for me. Okay? You like derangement? I like derangement better, I don't know what you mean. But it seems to me that actually the idea of marketing the concept of there is this, this, this one thing which has a hundred bad things with it, just strikes me as a really interesting way of trying to reframe the argument.

• 28:47Stephen J. Dubner?

  But marrying that to what, where Chris was going with parenting, which I really applaud, because I think parents get off the hook really easy, way too easy. Because most kids will eat what they want to eat when it's available, right? And we're the ones that make it available to them. So what about using, I actually like malnutrition because I think- It connotes the fact that, yes, we used to have the problem that people were ill because they didn't get enough to eat. Now, they are still ill because they're just eating too much of the wrong thing. I actually find that paradox appealing, but that's just me personally. But what if you could marry the concept of malnutrition with shaming? What about shaming the parents? What about this is a crusade that parents are really...

• 29:24Speaker 14

  Well, that's sexy. If you mailed 100 million homes, is your child suffering from metabolic derangement? They're going to read that. Is your kid fat? Goes right in the trash.

• 29:35Stephen J. Dubner?

  Exactly. Right.

• 29:36Speaker 13

  I mean, just picking up on this, one of the things we found in our research, and we actually haven't talked about this yet, is when you focus on obesity in kids, you also have a side effect in that you'll increase eating disorders among kids. And that has big cost also. We found that by just focusing on healthier eating and physical activity, you can reduce obesity in kids and reduce eating disorders at the same time. So I think, I agree with, don't focus on fat among kids or obesity as a topic, but focus on the behaviors and the environment you want to change.

• 30:17Stephen J. Dubner?

  Several of the most intriguing ideas in the lightning round came from one person, Harvard economist David Leibson.

• 30:23Speaker 10

  I very much like the idea of a tax, and I have the feeling that, you know, to an economist, that's delicious.

• 30:34Stephen J. Dubner?

  Leibson proposed a grand experiment where, in some places, you'd put a tax on unhealthy foods, and in other places, leave prices the same, to see how consumers would respond and how much it would cost to nudge people away from those cheap, empty calories. Leibson also had an idea for a piece of caloric monitoring jewelry.

• 30:57Speaker 10

  Imagine you had a bracelet. That a kid wore, or an adult wears, if I had this, it would affect my behavior. And as I go into a meal, it starts registering 200, 700, 900, 1400 calories. And as it tells me I'm eating more and more in this feeding episode, it starts to change its color from green to yellow to orange to red. And then it starts pulsing, red, red, red, red, once I get way out of range.

• 31:22Speaker 04

  And squeezing it tighter and tighter.

• 31:25Speaker 10

  There's many aspects of this that may seem effective if the technology could be developed. And we can put that issue of how to develop the implanted probe so that you actually can get this external measurement. Though there are increasingly external diabetic measures that can pick stuff up like this. But the reason I mention this is that it goes back to the reinforcement learning point that I made earlier, which is organisms are very good at learning when the stimulus and response are tightly linked in time. And they're terrible at learning when stimulus and response are separated by like 10 minutes, let alone five years. So if we could somehow help people realize what you just ate is doing it now,

• 32:10Speaker 10

  I think people would feel much more negativity towards overeating.

• 32:16Stephen J. Dubner?

  And David Leibson's final idea? Let me just say, a few of you might find this a bit distasteful.

• 32:24Speaker 10

  Imagine a world where I could have, you know, consume a parasite that could not reproduce, and it would go into my bloodstream, and it would basically make the things that I eat, you know, ineffective as nutrients, and they would flush out of my body. And because the parasite doesn't reproduce, I can control how much I want. And if I'm too skinny, I don't take the parasite. And if I'm getting fat, I take the parasite. So what I'm proposing is a world where, hey, we love eating. I loved my Reuben sandwich last night. And I could have more of those, in principle, up to a limit, if I had an ability to kind of turn off my body's capacity. My body's so efficient at turning... Calories and nutrients into more of me.

• 33:05Speaker 10

  And if I partially incapacitated that in a way that we could control, a way that was safe, in a way that, you know, wouldn't it be fantastic? Because then the food companies could sell more food.

• 33:15Speaker 01

  Okay. So just, it's always been my belief that when there's one economist in the room, you feel like you're really smart, and when there are two, you feel really dumb. So just an example of this, so David talked about, about his parasite. I spent all afternoon learning about tapeworms yesterday, because all economists think exactly alike about these things. And I came to believe that, obviously, you can do better than the current tapeworm, but there are some pretty good tapeworms out there right now. There's, there's certainly bad tapeworms. There's a fish tapeworm, it turns out, which you wouldn't really want anybody. But as far as I could tell, I think it was the beef tapeworm. And there's all sorts of tapeworms that actually are not perfect, but are, are pretty good

• 34:00Speaker 01

  already at doing what David wants them to do. And I'm sure if we could domesticate them with the kind of effort we put into dogs and, and cows and things, we could make tapeworms are, are some of the most loyal and serviceable pets that would ever be out there.

• 34:25Stephen J. Dubner?

  That was Steve Levitt and before him, David Leibson. As you can tell, obesity is one of those problems that is so tricky that some of the possible solutions are bound to be outlandish. It's hard to say how or if any of the ideas you heard today will be acted upon. Steve Levitt and I were just the facilitators of this discussion. Other people will be the executors. When it was over, Levitt and I held a brief postmortem.

• 34:57Stephen J. Dubner?

  We closed the proceedings with an experiment, something you've dreamed about, that you've talked about for years and years. Why don't you describe that and tell me what effect you think it had?

• 35:07Speaker 01

  So, one of the issues we didn't talk a whole lot about during this conference was self-control and the fact that many people who want to lose weight are unable to do so because they, in the moment, end up eating more than they would like to and regretting it later. So, there are different solutions to that. One very aggressive and invasive solution is bariatric surgery, which makes it difficult for you to eat a lot. But, my father really put the idea in my head many years ago, when he suggested that if you really don't want to gain weight, whenever you start to think you're hungry, you should carry around a little jar of, like a baby food jar, that's filled with human vomit, and just open it up, take a whiff, and you won't have any desire to do

• 35:52Speaker 01

  it. Now, turns out, it's operationally hard to figure out how to get vomit into a baby food jar, but my friends at www.liquidass.com have actually done their favor for us. So, I recently discovered, you can buy in a bottle, a little spray bottle or squeeze bottle, the most revolting smelling things in the world, which all you need to do is take one or two whiffs of them, and you think you don't need to eat for a long time after that. And so, we brought it out to show the obesity researchers and to take their pulse on it. So, as we passed these bottles around the room and invited people to have a sniff, I noticed that almost all of the outsiders, the economists and the sociologists, the

• 36:35Speaker 01

  scientists, many of them took a good, deep whiff, but none of the obesity experts went anywhere, not one of them wanted to take a whiff of that stuff. I think it tells you something.

• 36:45Stephen J. Dubner?

  What does it tell you?

• 36:46Speaker 01

  I'm not sure, but I'm gonna have to think about it, but the division in response was notable.

• 36:52Stephen J. Dubner?

  And liquid ass. Can't we randomly assign this to be about the impact?

• 37:01Speaker 14

  It's like a lottery.

• 37:05Stephen J. Dubner?

  I mean, I realize it's kind of jokey, but do you think it's a personal responsibility idea here? In other words, do you think that the experts have come to divorce the idea of obesity and personal responsibility to the point where, eh, the problem is not really on the end user so much, and they don't need to work so hard?

• 37:23Speaker 01

  It is an interesting point you raised that I do believe that the outsiders were much quicker to think about the problem at the individual level, about self-control, about why do individuals become obese, whereas the experts in the field think of it much more in environmental terms, and what are the food companies doing, and how are things marketed, and how the individual is not really the actor that they acted upon. It is an interesting difference.

• 37:56Speaker 01

  Dwayne from the foundation, I have to say, he's stuck his nose deep in each, and he had, of course, the classic quote. You remember exactly what he said? Acid and vomit smell different? He said, "They're really not the same."

• 38:29Stephen J. Dubner?

  Coming up next time on Freakonomics Radio, of all the problems with the US tax system, one of the biggest is also the most obvious: too many people don't pay what they owe. Now, how much money are we talking about here? At least $450 billion, billion with a B, every year. So, for a minute, forget about wholesale tax reform. What are some good ideas to simply get people to pay up? Here's one, imported from England.

• 38:58Speaker 15

  So just telling people that nine out of 10 other people pay their tax on time is enough to create a 15 percentage point increase in the number of people who then just pay their tax.

• 39:08Stephen J. Dubner?

  Using the herd mentality and other nudges to help close the tax gap, that's next time on Freakonomics Radio.

• 39:22Speaker 02

  Freakonomics Radio is produced by WNYC, APM, American Public Media, and Dubner Productions. This episode was produced by Susie Lechtenberg. Our staff includes Catherine Wells, David Herman, Borey Lam, and Chris Bannon. Colin Campbell is our executive producer. If you want more Freakonomics Radio, you can subscribe to our podcast on iTunes or go to Freakonomics.com, where you'll find lots of radio, a blog, the books, and more.

• 40:05Stephen J. Dubner?

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• 40:38Stephen J. Dubner?

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• 41:32Stephen J. Dubner?

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