Show Notes
In today's grocery stores, you can find more sugary snacks, artificial ingredients, and ultra-processed packaged foods. At the same time, the United States has seen an increase in obesity, which is costing our healthcare system, too. Nutritionist Marion Nestle says the problem today isn't that Americans don't know how to eat healthy, rather the food environment that we live in has made it much harder to do so.
In this episode, she discusses what policy changes are needed—from the way food studies are funded, to offering nutrition education in schools, to regulating the food industry better. Nestle is a Professor of Nutrition, Food Studies, & Public Health at New York University, Emerita, and the author of many books, including Food Politics: How the Food Industry Influences Nutrition and Health, and Slow Cooked: An Unexpected Life in Food Politics.
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(Episode published March 30, 2023)
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Related:
- Marion Nestle's Unexpected yet Impactful Life in Food Politics—Worth
- How Marion Nestle Changed the Way We Talk About Food—GQ
- “Slow Cooked”: How Marion Nestle Revitalized Food Studies—Forbes
Transcript:
Paul Rand: How can we improve communication at work? Are stock markets really efficient? Should we let algorithms make moral choices? How will climate migration affect our societies? The Chicago Booth Review Podcast addresses the big questions in business, policy, and markets, with insight from the world’s leading academic researchers. We bring you groundbreaking research in a clear and straightforward way. It could help you make better decisions, work smarter, and maybe even become happier. Find us wherever you get your podcasts. We all know that eating healthy is important, but in practice, well, that’s much harder to do.
Tape: They’re chocolatey with crisp baked wafers and crunchy peanut sprinkled on top.
Tape: Marshmallows and chocolate graham crackers, yum.
Paul Rand: Are you craving sweets yet?
Tape: Startling new insight into the addictive power of sugary, salty, and fatty foods? Would you believe doctors have found that cravings for junk food may be as strong as an addiction to heroin or cocaine?
Paul Rand: These days, more sugar, artificial dyes, and preservatives are sneaking into our foods.
Tape: So the question I have is, why are they so addictive? And some may ask. Tasty. It’s delicious.
Paul Rand: It’s no secret that these foods aren’t good for us, and the health implications are massive. Today, around 42% of adults in the US are obese, and alarmingly, obesity is rising among children too.
Tape: In the US right now, one in five kids are considered obese by doctors.
Paul Rand: But it’s not just here. It’s a global problem. Obesity has tripled since 1975. So how did we wind up here?
Marion Nestle: We live in an environment in which we are surrounded by messages to eat more.
Paul Rand: That’s Marion Nestle, a professor of nutrition, food studies, and public health at New York University. She is famously, and infamously in some circles, known as one of the food industry’s biggest critics.
Marion Nestle: The whole purpose of a food company is to get people to eat more of its products.
Paul Rand: Public health experts are well aware of this fact, and yet, it seems like our food environment has only gotten worse.
Marion Nestle: The study has just come out saying that the cost of obesity in healthcare and lost productivity is going to amount to trillions of dollars. And it’s going to affect every country in the world, and it’s going to affect people’s personal lives, in not very nice ways. We don’t have a healthcare system in the United States, but how are people’s health problems going to be paid for? Not easily.
Paul Rand: Welcome to Big Brains. On our show, we translate the biggest ideas and complex discoveries into digestible brain food, big brains, little bites, from the University of Chicago Podcast Network. I’m your host, Paul Rand. On today’s episode, the science of nutrition and food politics. I wonder if I can start off by maybe just getting you to talk about your training, your background, your education, because I think that is quite fundamental to how you approach the field of nutrition.
Marion Nestle: Well, I’ve always been interested in food. I love it. I think food is one of life’s greatest pleasures, something that you get to have a pleasure several times a day. And I actually went to college wanting to study food. But the options were dietetics or agriculture. I was a bacteriology major in college and then, went to graduate school in molecular biology. I wanted to understand how science worked, and it was really fabulous training. Because you can’t see what you’re doing in molecular biology. You have to infer it from the kinds of experiments that you’re doing. Everything is at the molecular level. The whole game in graduate school was to try to figure out what was wrong with everybody’s experiments, not in a particularly hostile way, but really, in a very intellectually challenging way. I found it very intellectually challenging and liked it a lot.
And I didn’t really get back to food until my first teaching job. I was at Brandeis University in the biology department, teaching cell and molecular biology, and got handed a nutrition course to teach. And you had to teach whatever the department wanted or needed. And students were sitting in the chair’s office demanding human biology classes. And they offered me a... I could do physiology or nutrition. I picked nutrition, because I thought it would be fun. And was it ever. And so, that kind of critical thinking that I was trained to do, I was able to use when I started looking at nutrition research, which is so much easier to deal with than molecular biology. And I tell the story in my memoir about a nutrition class that I had just been handed to teach. And so, I went to the library and started reading these studies in nutrition, and I would tell the story about it. It was an incredible experience, because the studies were done on six people, who were incarcerated in one way or another. And the famous one was the vitamin C study.
Paul Rand: The scurvy study.
Marion Nestle: The scurvy study of vitamin C, and it was done in a prison, which you can’t do anymore, for ethical reasons. And during the study, two of the prisoners escaped, and I thought, “oh, this is not a well controlled clinical trial.”
Paul Rand: Well, one of the lines that I read and I was quite impressed with, you said, “I have been attacked lots of times for my opinions, but never on my science.”
Marion Nestle: Yeah, it’s true. The science is there.
Paul Rand: These days, it’s impossible to escape the bombardment of nutrition advice and “research.” There are tons of diets and fads out there from gluten free to vegan.
Marion Nestle: Keto and paleo and this nutrient and this food and this diet type of diet and fad and this kind of fad and that kind of fad.
Paul Rand: It’s hard to keep up with all of the new trends. But as a nutrition expert, who has read it all, Nestle says it really comes down to a few simple guidelines.
Marion Nestle: Dietary advice boils down to eat real food, which means not a lot of junk food. Maintain a reasonable body weight and eat lots of plants. That’s all there is to it.
Paul Rand: It’s changed a lot though, hasn’t it? If we look even back at the last 50 years or we look at the food pyramid back in the nineties, it really keeps evolving, and it seems to change constantly. Why is that?
Marion Nestle: Well, I actually don’t agree with that.
Paul Rand: You don’t?
Marion Nestle: No, I don’t think nutrition advice has changed at all. In the 1950s, Ancel Keys and his wife, Margaret, wrote the first set of dietary guidelines for chronic disease prevention.
Ancel Keys: The facts are simple. The chief killer of Americans is cardiovascular disease, disorders, and degeneration of the heart and blood vessels. Here are vital statistics. They show that this problem here in America is the worst in the world.
Marion Nestle: And they say, “eat less saturated fat, salts, and sugar. Eat more fruits and vegetables. Don’t drink too much alcohol. Get plenty of sleep.” Now, you tell me what’s changed in that.
Paul Rand: All right, so that’s a really interesting, and you’re right, that’s the exact same thing we hear today. What are we not learning with that straightforward, simple advice she gave? Why in the world is the world getting more obese?
Marion Nestle: What happened? I could tell you what happened. I’ve got an elaborate explanation for what happened, beginning with the election of Reagan as president, that changed everything in the United States.
Ronald Reagan: Government is not the solution to our problem. Government is the problem.
Marion Nestle: Up until then, the percentage of obesity in the population was quite low. After 1980, it went up very rapidly. Genetics did not change in 1980. What changed was the food environment. What happened in 1980 with Reagan’s election was that corporations were given a free hand, and that free market ideology became the ideology that everybody accepted.
Ronald Reagan: It is my intention to curb the size and influence of the federal establishment and to demand recognition of the distinction between the powers granted to the federal government and those reserved to the states or to the people.
Marion Nestle: By that time, food was already beginning to be enormously overproduced. All of the effort was to produce as much food as possible. The number of calories in the food supply from 1980 to 2000 went from an average of 3,200 a person per capita, men, women, little tiny babies, to 4,000. So there was an enormous increase in the amount of calories available in the food supply. There was also an enormous increase in the number of calories that people were eating. So portions went up. Food became available in places that it had never been sold before. Libraries, bookstores. And then, people wonder why people were eating more. Well, people were eating plenty more calories. A number of calories in people’s diets went up, and people gained an average of 10 to 20 pounds.
Tape: It’s morning again in America.
Marion Nestle: I had a doctoral student, Lisa Young, who did her dissertation on the change in sizes of portions from 1980 to 2000, and demonstrated that muffins, which, in the early 1980s, were mini muffins, are now 600, 800 calories. They’re enormous. It’s not intuitively obvious to understand that larger portions have more calories. If you think about it, it makes sense, but in fact, humans don’t react to portions that way. And we could prove that by asking students in a class how many calories were in an eight ounce soft drink and how many calories were in a 64 ounce soft drink. And the students, that’s an eight times difference. Eight times a hundred is 800. The average calories was 300. And these students are not that mathematically challenged. So when she went back and asked students why, they just said “800 calories in a soft drink is impossible.” So there’s something about portion size that makes everybody think it’s smaller than it is.
Tape: Big Gulp, 7-Eleven’s big drink for a big thirst.
Paul Rand: From the 1980s through the 1990s, soda consumption skyrocketed. At its peak in 1998, Americans were drinking 53 gallons of soda per capita.
Marion Nestle: They go down really easily. You have no idea how much sugar there is in sugar sweetened beverages, because the flavors hide the sweetness. So you really don’t realize how much sugar you’re getting. And there’s tons and tons of evidence that sugars in liquid form are absorbed rapidly, raise blood sugar and insulin levels, and do all kinds of bad things.
Paul Rand: But how do you guide people on how much is the right amount?
Marion Nestle: Well, there are sort of general recommendations. And the general recommendation is 10% or less of total calorie intake. If you’re on a 2000 calorie diet, then that’s 200 calories from sugar divided by four. So it’s 50 grams a day. That’s 12 teaspoons. The reason that sugar is a problem is because everybody loves it. They want every food they eat to taste sweet, and they can’t stop eating it.
Paul Rand: Something else changed in our food environment from the 1980s through today. And it may be the worst offender when it comes to our public health crisis, processed foods.
Marion Nestle: We love ultra processed foods, because they’re designed to be irresistibly delicious. You can’t eat just one.
Tape: Ultra processed foods make up more than half of all the calories in the US diet. And I know that sounds scary, and I don’t even know why, but...
Tape: Very much so.
Marion Nestle: The classic example that’s used to explain what ultra processed foods are is that corn on the cob is unprocessed. Canned corn is processed or minimally processed, and Doritos are ultra processed.
Tape: It’s the big crunch with the big cheese taste.
Marion Nestle: They don’t look anything like corn. You would never know what was in them unless you read the ingredient list, and you can’t eat just one. Or maybe you can. I certainly can’t.
Paul Rand: Well, tell me what happens in our bodies, if you can, when we are eating these highly processed foods.
Marion Nestle: We don’t really know. The one clinically controlled study that has examined this question, I think one of the most important nutrition studies ever done was the one that was done in 2019 at NIH, where people were put in a controlled metabolic ward. They were given either ultra processed food diet or a diet that was processed but not ultra processed. The people who were eating the food couldn’t tell the difference. They were matched in nutrient composition. And to the investigators’ absolute surprise, when people were on the ultra processed diet, they ate 500 calories a day on average more than they ate when they were on the other diet. 500 calories is a lot. It’s a lot. It’s a pound a week. And they gained a pound a week while they were on that diet, without realizing that they were eating more. So he’s trying to figure out why.
And the most obvious thing was that they were eating more quickly, but he didn’t think that that accounted for it enough. And so, he’s done the first study to examine it, and he said it’s the hyper palatability, the fact that these people just love eating these foods and don’t even realize it. And the calorie density, meaning that these are highly caloric products, and we really like calories. And now he’s doing further studies to try to figure out what’s going on. But we don’t really know the answer to that. All we know is that, when people are given ultra processed foods, they eat a lot of them. Or as somebody explained to me, if you’ve got a bag of Oreo cookies in front of you, it’s really hard to stop. If you’re eating a salad, there’s a point at which you have enough salad. There’s never a point at which you have enough Oreo cookies, and you’re confronted with that all the time. You’re confronted with billions and billions of dollars spent on advertising, products that are not necessarily healthy.
Paul Rand: Did you see the recent multi-billion dollar lettuce campaign?
Marion Nestle: No, I did not.
Paul Rand: I didn’t either.
Marion Nestle: Exactly.
Paul Rand: This dynamic is what led Nestle to develop her own niche in the nutrition field. She realized the issue wasn’t just the food itself, but the food environment that we live in, and that environment is dominated by what she calls “food politics.” That’s after the break. Have you ever wanted to learn more about the life story of our guests or wondered what other world-changing research was happening this week? Well, now we’ve got you covered. Subscribe to the new Big Brains Insider from the University of Chicago. The Insider is a biweekly email newsletter with exclusive content featuring expanded guest interviews, groundbreaking research we are following, and other fun behind the scenes content.
If you love Big Brains, you’ll love the Insider. Visit our website to opt in now at bigbrainspodcast.com. Big Brains is once again participating in the UChicago Giving Day March 29th and 30th. Your contributions help us continue to highlight more pioneering researchers and the impact of the work that is reshaping our world. If you like the show, please consider supporting us. A link is on our website at bigbrainspodcast.com. In 2002, Nestle published the book that would define the future of her career, and it would change the way the world thought about the food industry. It was called Food Politics.
Marion Nestle: Well, food politics is something I’ve been writing about for more than 20 years now. Everything about food is political. Everybody eats. Everybody buys food. It’s an enormous industry composed of everything from agricultural production to transportation to retail sales to restaurants to everything that you can think of connected with food. There’s an enormous amount of money involved in it. And the purveyors of goods in that system want to make sure that their profits are maximized at all times. And food companies are not social service agencies, they’re not public health agencies, they’re not non-for-profit organizations. They’re businesses with stockholders, and they’re a for-profit business.
Their job is to give profits to stockholders, as their absolute primary priority. They’re not in the business of making people healthy. They’re in the business of selling products. And so, if you were following Michael Pollan’s basic dietary advice, eat food, not too much, mostly plants, nobody’s making much of a profit off of that. The profits are off of junk foods. Those are the most profitable foods, foods that we’re now calling “ultra processed,” which are industrially produced, can’t be made in home kitchens, and, we now know, encourage people to eat more.
Paul Rand: And at one point, you wrote, “it appears as if the government and the food industry are collaborating to support a food environment that encourages people to eat more food than they need.” And I wonder, if you think about what the government’s role is, what is it? And how are they actually making it worse for us?
Marion Nestle: Well, the government is involved in every aspect of food production and consumption that you can possibly think of, starting with agriculture and agricultural subsidies and where they go. And the fact that 90% of United States corn production has nothing to do with food for people. Half of that 90% goes to feed animals, and the other half goes to fuel automobiles. That’s our food system. That makes no sense whatsoever. We’re not producing food for people. We’re producing food for animals, and everything else is sort of minor in comparison. That’s agricultural policy. To me, it makes no sense whatsoever. The government is involved in nutrition education, through the dietary guidelines for Americans, which get longer and more complicated every year and confuse people enormously, because they’re focused on details, not on the bigger picture. The government is involved in food labeling, which nobody understands, and nobody understood from the get-go, because when the FDA tested models of food labels in focus groups and other kinds of testing, nobody understood any of the models they were using. And they picked the one that was least worst understood.
So there’s basically no useful nutrition education in this country. There’s no money going to nutrition education. The government does food safety. We could sure do a better job of that. The government regulates advertising. We could sure do a lot better job of putting some restrictions on marketing of junk foods to kids, for example. And the tax policies allow food corporations to deduct the cost of marketing as a business expense. I could go on and on and on. There’s so many ways. They’re not things that you usually think about, but the result of government policy is a food environment that is very good for business and not very good for public health. And I’d like to see that changed.
Paul Rand: It’s been a long time coming, but government regulations are getting better. The FDA recently introduced a new rule that would crack down on super sugary cereal brands.
Tape: Cereal may not be as healthy as you think. The FDA recently issued a proposed rule that updates criteria for claiming of food is healthy, and it takes aim at added sugars.
Paul Rand: Fruit Loops, Fruity Pebbles, and Lucky Charms.
Tape: Cereal seems a wise way to start the day, with claims of whole grains, fiber, protein, heart healthy. But look closer, and you may find a not so sweet secret.
Tape: And what we’ll find is a lot of America’s favorite cereals, even those that they think are healthy, will no longer cut or make that definition of healthy.
Paul Rand: And guess what? Those cereal brands aren’t too happy. They claim their cereals are indeed healthy.
Marion Nestle: I have a whole book on it. It’s called Unsavory Truth, How Food Companies Skew the Science of What We Eat. And it has to do with corporate funding of nutrition and food research.
Paul Rand: And this is where Nestle’s work cuts close to home for our research focused podcast. Her work has shown that, in the game of food politics, scientists aren’t always the neutral parties that they’d like to think of themselves as.
Marion Nestle: The makers of any product that you can think of on the market are funding research, in order to demonstrate that their product has some benefit for health or is safe or is benign or is whatever. And I, on my blog, foodpolitics.com, every Monday, I post one of these studies. Each one is funnier than the next, because I can predict from the title of a study who funded it. Or if I know who the funder is, I know what the results are going to be, because they pay for what they get. And it’s not that the people who are doing this research are bought, in the most obvious sense. They’re influenced, but don’t recognize the influence. And there’s a great deal of research on industry funding, that shows that the recipients of industry funding really don’t realize the ways in which they’re being influenced. In drug industry funding demonstrates that drug companies that fund basic medical research get the results they want.
And I find that, in order to deal with food companies, because I deal with food companies all the time, I have to go to an enormous effort to think, in every dealing with a food company, “am I putting myself in a position where my integrity is going to be compromised or in which my thinking is going to be influenced?” And it’s hard. It’s not easy to do that, but it’s just, by the most remarkable coincidence, the studies that are industry funded almost always come out in favor of the funder’s interest.
And I get letters all the time from food corporations or from trade groups saying, “we’ve got this amount of money, and we’re looking for studies that demonstrate the benefits of our product.” Well, they’re not going to fund anything that’s not likely to show a benefit. That’s where the bias comes in. So you can design a study to demonstrate benefit, and you’re giving the funder exactly what the funder wants. And your study comes out exactly the way the funder wants it. I think this is very unfortunate. A lot of this has to do with the lack of government funding, but also, I think, because people just don’t realize that this is about marketing, not science.
Paul Rand: But even if we did manage to have better research into the food that we eat, how much would actually change? Most people know to eat more whole foods, mostly fruits and vegetables. The problem is what they eat in between. Changing the politics of our food environment, well, that’s complicated.
Marion Nestle: No, I think there are two things that would be very useful. One would be to repeal the Supreme Court’s decision on Citizens United, which allows corporations to put as much money as they want into election campaigns, without having to disclose the amounts that they’re doing. We need a publicly funded election system, so that people who care about public health can run for office without getting corrupted. Right now, we have a corporate controlled election system, because they’ve got the money. So that’s one. And then, the second one, I think, is we have to change Wall Street. The way that Wall Street evaluates corporations is by how much money they make for their stockholders.
There have been some attempts by business leaders to try to say social values need to be incorporated into corporate activities. And corporations need to be evaluated on what they’re doing for the environment and what they’re doing for public health. But until Wall Street changes the way it evaluates corporations, based on those kinds of values, they can’t budge. They can do lip service to it. And a lot of corporations are doing lip service to environmental protection, but it’s not real. So these are big system changes that need to be done. How do we do that? We need to change our government. When students ask me what can they do, I tell them, “run for office.” You either have to develop grassroots power or you have to develop top down power. I think we need both.
Paul Rand: The latest solution being put forward today doesn’t so much look at these systemic changes. Rather, it promises to fix everything with just a simple little drug.
Tape: Ozempic.
Tape: Ozempic.
Tape: Ozempic.
Tape: Ozempic.
Tape: Ozempic, a popular medication typically prescribed for people with type two diabetes is reportedly being used off label for weight loss by social media users.
Tape: This question, I had to ask what this was earlier, but how does Wegovy help you lose weight? I guess we start with, what is Wegovy?
Tape: I love this.
Tape The weight loss drug, Wegovy, also made by Novo Nordisk, is FDA approved for weight loss.
Paul Rand: These drugs have become famous for their seemingly miraculous ability to help patients lose weight.
Tape: A new crop of anti-obesity drugs are proving remarkably effective, cutting body weight by an average 15 to 22%. These medicines, including Ozempic and Wegovy, could trigger a shift in how doctors treat this.
Paul Rand: There’s a lot of discussions these days about different drugs, i.e., Ozempic, which was developed to help people with diabetes, but is now actually not uncommonly surprised to help people lose weight. How do you feel about this approach? And if we can’t manage the obesity issue through the food we’re consuming and the changes in the companies, is handling it pharmacologically an option in your mind and a good option?
Marion Nestle: No. From a health promotion, public health standpoint, you want to prevent type two diabetes. If you want to prevent type two diabetes, what you want to prevent is weight gain. Because weight gain is so closely associated with type two diabetes. It’s not that everybody who is overweight gets type two diabetes, but if you look at people with type two diabetes, roughly 90% of them are overweight by the usual standards, because we live in an environment in which we’re supposed to eat more, not less. So that’s on the one hand. On the other hand, I don’t treat children and adults who have obesity. I’m not somebody who does that, but I hear from people who do treat, and they are happy to have a tool, at long last, that might actually do some good. I’m not going to argue that. From my standpoint, I think in public health terms. I’m a public health person.
I think we really need public policy. We need government action. We need everybody to try to figure out what to do about obesity. It should be a source of enormous concern, and the government should be funding all kinds of studies to try to figure out some effective way for making it easier for people to eat more healthfully. So that’s on the pessimistic side. I don’t see that happening. On the optimistic side, I teach students, and I get to deal with young people who are interested in food and who want to use food to change the world for the better. They’re interested in studying about food. We have food studies programs in my department at NYU, and the students who come into that, at the undergraduate, masters, or doctoral level, want to change the world, using food as a means to do that. And because food connects to absolutely every problem in society in one way or another, they have the opportunity to do that. And I want to encourage them in every way I can.
Paul Rand: Final question, if I can, I’m going to follow you into a supermarket. What am I going to find about how you’re shopping, what you’re putting in your cart?
Marion Nestle: I try to have a shopping list and shop with blinders on, so I don’t get hooked by the things that are being pushed at me. I read food labels, mainly because they’re so entertaining. I just love reading food labels. “What are they doing now?” And I look at them with a very skeptical molecular biology lens. I find supermarkets just more fun than anything. And healthy diets don’t necessarily have to be more expensive. They could be just as delicious. You don’t have to give up the pleasure of food deed healthfully. And it’s better for kids. It’s better for adults. It’s better for old people. It’s better for everybody.
Paul Rand: If you’re getting a lot out of the important research shared on Big Brains, there’s another University of Chicago Podcast Network show you should check out. It’s called Entitled, and it’s about human rights, co-hosted by lawyers and new Chicago law school professors, Claudia Flores and Tom Ginsburg. Entitled explores the stories around why rights matter and what’s the matter with rights.
Matthew Hodapp: Big Brains is a production of the University of Chicago Podcast Network. If you like what you heard, please leave us a rating and review. The show is hosted by Paul M. Rand and produced by me, Matt Hodapp and Lea Ceasrine. Thanks for listening.
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