Multicolor fruit candies background

How the Food Industry Manipulates Nutrition Science: Five Questions for Marion Nestle

Marion Nestle may be America’s foremost public nutrition warrior. The scientist, activist, and author has been advocating for clarity in food research and marketing for years, and has been highly critical of the food industry. Her last book, “Soda Politics: Taking on Big Soda (and Winning),” tackled the soda industry with insightful reporting — especially on how research funded by Coca-Cola aimed to increase profits by misleading consumers.

Currently an emerita professor of nutrition, food studies, and public health at New York University and a visiting professor of nutritional sciences at Cornell, Dr. Nestle is back with her latest book, “Unsavory Truth: How Food Companies Skew the Science of What We Eat.” This time she chronicles how meat, dairy, and other large food producers manipulate nutrition science by funding both research projects and individual researchers with the goal of demonstrating the benefits of their products —more marketing than science, as she puts it.

For this installment of the Undark Five, I spoke with Nestle (pronounced like the English verb “to nestle”) about the genesis of her new book, her continuing fight to confront the food industry over transparency in its research, and what the public can do about it. Our telephone conversation has been edited and condensed for space and clarity.

Undark: Why have you written this new book?

Marion Nestle: Well this one actually grew out of my other books. When I started out looking at the food industry, I could see that when food companies funded research, their research questions were phrased in such a way that the results could be used for marketing purposes. It became clear to me that this wasn’t about basic science and nutrition, but more about how the benefits of a product could be established according to the funder.

That was pretty obvious to me even back in 2001 when I started writing about the topic. Since then I’ve discovered that food companies in trade associations, in general, are funding research. I get letters all the time from these companies looking for proposals to show the benefits of their products. So the companies are quite frank about it — they’re looking for evidence of benefits. That’s not science. That’s marketing research.

UD: One chapter is dedicated to your research into Coca-Cola. How are they, in particular, manipulating research for their own benefits?

MN: When I started doing research on “Soda Politics,” I came across research conducted by Coca-Cola that was designed to demonstrate that sugary beverages were harmless, that they did not have anything to do with obesity and diabetes, and that research which found problems with sugary beverages was so flawed that you shouldn’t pay any attention to it. So this Coca-Cola funding was essentially designed to produce studies that would be beneficial to their company.

After that book went to press in 2015, The New York Times published an investigative article for which I had been interviewed. The article talked about Coca-Cola’s funding of a research group at the University of Colorado called the Global Energy Balance Network that brought together researchers who were arguing that physical activity was far more important than diet in maintaining weight and not becoming obese. And that viewpoint is so contrary to the large body of evidence.

I got so many calls from reporters who were shocked by this. They just could not believe that a company as prominent as Coca-Cola would do something so crass as to fund research in their own interests, and that researchers at universities would take money from a company to carry out studies. But they do.

UD: Can you outline what we now know about the health risks, and benefits, of eating meat and dairy products?

MN: Well, the World Cancer Research Fund and the American Institute for Cancer Research just came out with their third report on diet and cancer, and they list red meat as a probable cause of cancer. The evidence is also really strong that processed meats are a risk factor for cancer too. So, this is a major research review from a body of experts saying that meat is carcinogenic.

The issue around dairy products is much more complicated, and evidence is a little harder to establish. I’ve come to the conclusion that if you don’t eat too much dairy and if it’s in a form that is not full of saturated fat and sugar, then it’s probably O.K. But that’s true for most foods. Essentially, some studies show that dairy is harmful and some studies show it is beneficial, so the truth is somewhere in between.

UD: How do you think the forces of capitalism have shaped biases in nutrition research and marketing in recent decades?

MN: This takes us back to 1980, which is kind of the base point for the rise of obesity in the United States. A lot of things happened in 1980, and one of them was the election of Ronald Reagan with a deregulatory agenda, which seemed shocking at the time, but seems mild compared to what’s happening today. At the time, there was an enormous push in what is called the shareholder value movement, where a shift toward higher and quicker returns on investment was implemented. This new system required corporations to grow their profits every 90 days.

For the food industry, this was a disaster because it was already supplying more than 3,000 calories per day for every person in the country. So between 1980 and 2000, the number of calories per day per capita increased by between 800 and 1,000. Nowadays, we have 4,000 calories per day per capita, and food companies have to continue to sell all this in a competitive environment to increase profits. So these companies have had to look for ways to increase sales over time, and they’ve done that by advertising, particularly by targeting new groups like children and minorities.

I think this is a sufficient explanation for modern obesity. So it’s not that food industry executives are evil people — it’s that they have to grow their profits every 90 days or their stockholders get upset.

UD: How can citizens hope to understand nutrition data and empower their lives by teasing apart the biased from the unbiased studies — and where do you think society is moving now?

MN: Science literacy is very difficult to achieve if you don’t have a background in science. I would say that people should always be skeptical of breakthroughs — if something seems magical, then it’s probably not real. For example, there’s no such thing as a superfood.

Dietary advice for chronic disease prevention hasn’t really changed in the last 60 years. It’s still something that author and journalist Michael Pollan can summarize in seven words: “Eat food, not too much, mostly plants.’’ Really, it’s not much more complicated than that. The trick is to eat a wide variety of relatively unprocessed foods of all different kinds — things that are real. In fact, I think the most important piece of advice is not to eat too much.

As for where we’re headed, in the United States at the moment it’s very unlikely that the current government is going to make any positive changes in terms of consumer-friendly legislation. So we will need some sort of bottom-up grassroots movement to demand healthier and more environmentally-friendly foods.

Now, how that’s going to happen I don’t really know. Hopefully, if these articles about corruption in the research agenda of food companies keep coming out, then there may be some hope. I really think the public needs to be more skeptical and reporters need to do a better job of truth-telling around these issues. There really needs to be a huge wind of ethics blowing through the whole thing.

Conor Purcell is a science journalist based in Dublin. He is the founding editor of and can be found on Twitter @ConorPPurcell.