Is Your Diet Making You Sick? The Hidden Impact of Ultra-Processed Foods

CHRISTIANE AMANPOUR, CHIEF INTERNATIONAL ANCHOR: Next to the ubiquitous, yet harmful ultra-processed food. Dhruv Khullar is a physician and contributing writer for The New Yorker. He’s been investigating the dangers in our diets and spoke to Hari Sreenivasan about his findings.

(BEGIN VIDEOTAPE)

HARI SREENIVASAN, INTERNATIONAL CORRESPONDENT: Thanks. Dr. Dhruv Khullar, thanks so much for joining us. You wrote a piece in The New Yorker recently that is titled, “Why is the American diet so deadly?” And, you know, it would seem like as you dive into all of the research that there should be some sort of a simple answer, but there isn’t. Why?

DR. DHRUV KHULLAR, PHYSICIAN, WEILL CORNELL MEDICINE AND CONTRIBUTING WRITER, THE NEW YORKER: You know, it’s a really complicated issue. One of the things that we’re really starting to learn more and more about almost every day is the idea of ultra-processed foods. And that’s a really broad category. It’s one that, you know, we’ve only really had in our lexicon for the past 15 years or so. But our diet, the American diet has among the most ultra-processed foods in the entire world. And so, if you think about how we compare about 60 to 70 percent of our diet is considered ultra-processed, it might be half in France or a third in Spain. And so, we really are an outlier in this way and our rates of chronic disease and obesity track with that.

SREENIVASAN: So, can we just get kind of a definition on the table? What’s process? What’s ultra-processed? What — you know, if I’m looking around through my pantry or my refrigerator, how do I know the difference?

DR. KHULLAR: Yes, it’s a great question. So, people generally have a sense that ultra-processed foods, they sound just like bad food or junk food, but there’s actually a very specific scientific definition. And so, if you think about ultra-processed foods, you start at the very bottom. So, most foods when they come out of nature are unprocessed or minimally processed. So, you think about eggs or nuts or vegetables, and these group one foods, and those are generally considered natural and healthy. Then we get to group two, which is kind of culinary ingredients. And so, salt, butter, fat, sugar, these types of things. If you add the first group to the second group, you get the third group and that’s considered a processed food. Almost all the food that we have is processed in some way. You think about just buttering and salting your pasta, that’s now processed foods. It doesn’t mean that it’s a bad food. What we’re talking about here is that fourth group, group four foods. And that means that it has using unnatural ingredients or unnatural processes to get there. And so, a lot of these foods have high fructose corn syrup or hydrogenated oils or certain emulsifiers or thickeners, additives of all sorts, and that’s what we’re talking about when we’re talking about ultra- processed foods. But it’s a very broad category. And so, everything from gummy bears to canned kidney beans might fall into this one category. And so, we really need to be thoughtful about what are we talking about when we say ultra- processed foods are harming our health.

SREENIVASAN: So, what is the actual effect on our health when we take on these ultra-processed foods? Is it our ability to digest it or how we store it? I mean, you looked at really fascinating research, which actually had people eat pretty weird diets as much as they wanted for days on end.

DR. KHULLAR: Yes. So, it’s a great question. And we’re just starting to get really rigorous research on this. So, the first kind of research that put this on the map was broad scale survey research. And so, you might survey thousands or hundreds of thousands of people and say people who eat more ultra-processed foods tend to have higher rates of cardiovascular disease or dementia or any number of conditions. But what studies are doing now is they’re bringing people in the lab to try to figure out, hey, if you’re giving people 80 or 90 percent ultra-processed foods versus very little ultra-processed foods, what happens inside their body? The big — the headline finding here is that people tend to eat many, many more calories on an ultra-processed diet than on an unprocessed diet. And so, some of the studies that we’ve seen, you know, 500 more calories a day, 800 more calories a day on an ultra-processed diet versus an unprocessed diet. So, that’s the headline finding. Underneath that, there’s all sorts of interesting, provocative, early findings. You know, does it change our microbiome in some way, a bacteria in our gut, does it change our hormone levels and cause us to feel more hungry? Does it change our taste buds, for instance, are we more likely to crave salt and sugar and other things that are unnatural because we’re so used to ultra-processed foods and the kind of the high hit of those things that they offer. And so, those are the things that are still a little bit speculative or figuring them out. But the headline finding seems to be that we just eat more calories when we’re on an ultra-processed diet than when we’re on a minimally processed diet.

SREENIVASAN: You know, when you look at the longer arc of how long humans have been on the planet and eating food, right, this is almost a blink of an eye in the terms of when ultra-processed foods were manufactured and kind of introduced into our diets. And there are still societies on the planet who have far less of this than you and I might have access to today, right? Are there ways that we can compare, you know, culturally or geographically to say, hey, we kind of know that if you’re on a little bit more of a, you know, holistic, maybe, I don’t know, Mediterranean diet, or maybe it’s just less process that your health outcomes are better?

DR. KHULLAR: That generally seems to be the case. And so, countries that have had a more traditional diet that haven’t had this industrialization of their food system tend to have lower rates of obesity. You know, actually, the researcher that put this whole idea on the map was a researcher named Carlos Monteiro in Brazil. And what he found was he was tracking, you know, what are people buying when they go to the grocery store? He had all these receipts. And he said that people are buying less salt, less sugar, less fat. So, he’s thinking, you know, how are we having this explosion of obesity? And what he realizes that people just basically aren’t buying those things, they’re just getting them packaged in foods that are coming to them that are ultra-processed. And so, it’s not just thinking about those specific ingredients or specific nutrients, but how are they packaged? You know, what are the other additives that are going to these things? Why do they have such long shelf lives? Obviously, it’s preservatives allow for that. And those types of things are having a real impact on the way that we’re able to live our lives and to put food on the table.

SREENIVASAN: You know, so many of us have tried to listen or watch the food pyramid guidelines or whether it’s the — you know, the healthy meal plate that the FDA or the Department of Agriculture might recommend, like how we eat, you know, we’ve been told about it’s about counting calories. And then, we’ve told — we were told it’s not — all calories are not equal, right? I mean, what are some kind of simple guidelines that people can use to figure out how to moderate their consumption, maybe how to consume more of the healthy and less of the unhealthy?

DR. KHULLAR: Yes, I think that the most important advice I could get is, you know, as much as you can cook your own food, the better you’ll be, right? So, the things that you will never put as much salt and sugar and fat and cholesterol in your own food as, you know, a restaurant or a fast-food joint will put in your food. And so, my number one recommendation is to the extent that you can cook your food, prepare yourself all the better. You know, not everyone has the time or the convened — the ability to do that. A lot of fresh foods can be pricey. They’re not readily available. And so, from there, you know, I think think about how we can minimize the processing in what we’re eating. And so, there’s a big difference between an ultra-processed yogurt, let’s say that has one specific emulsifier that’s improving the mouthfeel of that yogurt versus Doritos or something that is like very heavily processed. And so, I think keeping to things that are less processed on that entire spectrum of processing. And I always go back to Michael Pollan’s, you know, famous adage, which is basically eat real food, not too much, mostly plants. And I think if you can stick to those, you know, six or seven words that’ll get you a lot of the way there.

SREENIVASAN: Well, how much of this has a social dimension to it, right? Like I kind of — I’m thinking right now, if you gave me the ZIP code of someone in a test cohort, I could probably give you a pretty decent guess as to whether or not that population has high rates of heart disease or diabetes just based on their poverty level, right? And whether or not they have access to whether they live in a food desert, whether — like the corner bodega is really the only place that they’re getting their food.

DR. KHULLAR: Yes, I think you’re getting an incredibly important point, which is we make some decisions about our food, but a lot of the decisions that we’re able to make are influenced by economics by, you know, our social status, by politics. And so, all these things kind of come together to produce a food environment. And the food environment around us dictates a lot of the options that we’ll have. And so, you know, the first step I think is to educate people, to help them understand how to make healthy decisions about their lives. But we also need to move upstream and, you know, talk with policymakers. There are things that we can do to change the subsidies in this country that subsidize some of the junk food, things like corn and soy that end up as preservatives in our food. There are potentially restrictions on certain types of marketing, especially for children. You know, people have talked about getting ultra-processed foods out of schools, which I think is a good idea. And so, there are things that we can do at a higher level to try to shape the environment in which people can make healthier decisions for themselves.

SREENIVASAN: We’re having this conversation as Robert F. Kennedy Jr. has been picked to be the Secretary of the Health and Human Services, and one of the things that we heard before and during his confirmation was that there is some bipartisan interest in some of the things that he’s talking about in terms of getting ultra-processed foods out of school lunches and so forth. Now, there’s got lots of other sort of controversial viewpoints that he has on lots of things. But I wonder whether or not this administration or any administration really has a chance at trying to decrease this, given that most of the companies that are making these ultra-processed foods are also very active in lobbying for their interests.

DR. KHULLAR: It’s such a good point. And you know, one thing that is important about this whole conversation is that we’re talking about it. It’s on the map now in a way that it wasn’t a few years ago. I mean, people have been concerned about chronic disease and obesity. But as you mentioned, there’s real movement behind particularly the idea of ultra- processed foods, but more generally trying to reduce rates of chronic disease in this country. And I think where we can make common cause across the aisle, we should definitely pursue those options. You know, it’s hard to say how much progress we’ll be able to make without having very specific proposals for what we’re going to be able to do, but the idea that people at the highest levels of government are concerned and talking about this in a really passionate way, I think, bodes well for the potential, at least, to make progress on this issue.

SREENIVASAN: So, what are the counter arguments? What have you heard from the food companies in kind of slowing this system down? Because clearly, they’re motivated by selling more of whatever it is that you’re buying and making more profits. But what do they say doesn’t need to be changed? Is it really just about individual responsibility? And look, I don’t control what you put into your mouth.

DR. KHULLAR: Well, you know, as you’re hinting at, you know, eating less is very bad for business. And so, these businesses want you to eat more. They want you to consume more calories, to buy more chips, to buy more junk food, whatever it might be. And so, I think there’s a couple of things to think about, not just the food companies, but there are legitimate concerns among researchers that ultra-processed foods that are — is an incredibly broad category. I mean, it covers a huge swath of things from whole grain, you know, breads and yogurts all the way to sugary beverages, processed meats. And so, I think one step that we need to do is to try to figure out what within this huge consortium of foods is actually the most harmful. I think what the research is showing is that if I could limit anything, it would be sugar sweetened beverages and processed meats. Those two things have probably the highest level of evidence regarding their harmful effects on the human body. So, I think that’s a good place to start, both in terms of educating people about it, but also nudging food companies away from those types of products. Look, I mean, the food companies are going to try to sell as much food as they can. And so, what we need to do is try to shape demand for some of these things. And some of that will happen through education, but some of that, you know, we’re already seeing through things like GLP-1 drugs and Ozempic, you know, people’s preferences are starting to change. And over time, it’s possible that that could turn the food system into a different direction that would be more helpful for everyone.

SREENIVASAN: Do you see that? I mean, either in your practice or anecdotally, or I guess there’s probably data. Out there. What’s the longer-term arc of what the GLP-1 drugs could not just be doing to the population that’s taking them, but the entire food industry that’s catering to all of us?

DR. KHULLAR: Absolutely. I mean, these drugs have been incredibly effective for so many people, including a lot of my patients. I’ve seen them, people who have struggled all their life tried one diet after another to try to lose weight are now able to really lose weight and keep it off in a way that they never were able to do. And it’s not just about weight. I mean, these things have really helpful for people and salubrious benefits for cardiovascular health, for liver health, for kidney disease. We’re seeing suggestions that they may help with things like addictive behaviors. And so, I think these are really important drugs. There’s also a kind of more general — but as you’re hinting at, there’s a potential to have a more general effect where people who aren’t taking the drugs could — there could be indirect positive effects as companies, whether it’s alcohol companies, tobacco companies, the food industry change and reformulate their products because the demand that used to be there is no longer there in the same way.

SREENIVASAN: Are there any countries on the planet, so to speak, doing this well or better? Because you see often comparisons to Europe that, you know, myself included, when we travel overseas, you feel like the fries taste different at a McDonald’s in London than they do at a McDonald’s here.

DR. KHULLAR: There are. I mean, so a lot of countries in Europe do not have the level of ultra-processed foods that we have in the American diet. And so, if you look at certain European countries, it might be half as much or a third as much in terms of the overall food supply that is ultra-processed. You know, a lot of this movement grew out of South America and Brazil and surrounding countries. And so, those countries have taken even more aggressive approaches towards ultra-processed foods. So, some companies have tried to limit it marketing of ultra-processed foods, particularly to minors. Others are starting to introduce taxes on the worst types of ultra- processed food. So, there are these policy levelers at policymaker’s disposal. We’ll see how aggressive they want to be. I think building the evidence base for some of these policy changes is going to be really important. The stronger evidence that we have, the more forthright we can be about the policy recommendations. But for now, I think, you know, moving forward with helping people understand the potential risks of consuming these types of products, I think, is the best first step.

SREENIVASAN: So, how do we kind of get smarter in that way, where we might be seeing, well, I guess in this case, disinformation because it’s actively and intentionally trying to disinform us so that we make a certain kind of purchase. But you know, how do we navigate this? How do we become food literate enough so that we can tell what’s something that we should avoid from not?

DR. KHULLAR: Yes. I mean, I think helping people understand what is going in their mouth, what is on their plates, where their food is coming from is so important. Empowering them to make decisions that are going to be good for their good for their long-term health I think is going to be really important. What’s so exciting, I think, about this potential movement is that it is bipartisan. You know, so many of the things that are going on in our country have become politicized and there’s real division around particularly things around public health. This is an area where still the left and the right in the center agree that chronic disease in the United States is a big problem. Most people agree that our diet is contributing a substantial way to those rates of chronic disease and people are motivated to make a change. And so, I think it’s a place where there is potential to make real progress.

SREENIVASAN: So, what is the kind of rule that you go by in your household, right? I mean, you are kind of an average family. You have kids. You’ve got a busy schedule. You know, you write that, ironically, when you were a resident, you were counseling people on diabetes and eating better. And yet, you’re taking processed foods in the hospital cafeteria.

DR. KHULLAR: Yes. I mean, I think — you know, I shared that anecdote just to suggest, you know, how difficult it is really to avoid ultra-processed foods, to avoid foods that aren’t good for you. You know, I’m here counseling people with heart disease or diabetes to eat healthier and here I am. It’s very difficult for even someone with knowledge and experience to find food that’s consistently healthy. You know, in our house, we try our best to cook every evening or to prepare food at the beginning of the week and eat it over the course of the week. Of course, we order in and we give into fries and pizza from time to time. But again, that the most important thing that I want to try to instill in my family and my children is that if you could prepare your own food, it’s almost always going to be healthier than anything you buy in a restaurant or had a fast-food restaurant.

SREENIVASAN: Dr. Dhruv Khullar, contributing writer to The New Yorker, thanks so much for joining us.

DR. KHULLAR: Thanks so much for having me.