Food additives exposed: The artificial dyes and chemicals to avoid | Marion Nestle

Those long, unpronounceable ingredients at the bottom of food labels—what are they really doing to our health?

We dive into the hidden world of food additives and the regulatory systems meant to protect us. While the U.S. allows companies to self-certify ingredients as “safe” without independent FDA approval, Europe and the UK take a stricter approach. But does stricter always mean safer?

Marion unpacks how these systems differ, which substances might be harming our health, and what consumers can do to reduce their risk.

This episode empowers you to take a more informed, cautious approach when navigating ingredient lists — and to better understand how food policy affects your plate.

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Transcript

Jonathan Wolf: Marion, thank you so much for joining me today. 

Marion Nestle: A pleasure to be here. 

Jonathan Wolf: So we always like to kick off this show with a rapid-fire set of Q and As from our listeners. And we have some very strict rules about this, Marion, which is you can say yes or no, or if you have to, a one-sentence answer. Are you willing to give it a go?

Marion Nestle: Oh, why not? 

Jonathan Wolf: Alright. Marion, are the health effects of all new food additives tested before approval? 

Marion Nestle: Of course not. 

Jonathan Wolf: Are there additives in our foods that are regarded as potentially carcinogenic? 

Marion Nestle: Some. 

Jonathan Wolf: Are there substances in our food that don't show up on the ingredients label? 

Marion Nestle: Probably. 

Jonathan Wolf: Do food colorings harm the health of children?

Marion Nestle: Some people say yes. 

Jonathan Wolf: What do you say? 

Marion Nestle: I think probably some. 

Jonathan Wolf: Finally, what's the most surprising thing that you've discovered about food additive regulation? 

Marion Nestle: That nobody's paid any attention to them until now. 

Jonathan Wolf: I'm holding in my hands a loaf of bread. It's a Wonder Bread that is sold in your hometown, New York.

I thought it would be fun just to look at this loaf of bread, which looks very much like any other loaf of bread, and do what I've slowly learned to do since I started working at ZOE eight years ago, which is turn it over and look at the ingredients on the back. 

I think most of our listeners would think, Well, there's flour, I guess there's yeast, there's water, there's probably salt, that sort of makes sense.

Marion Nestle: A little sugar to get the yeast going. 

Jonathan Wolf: Okay, maybe a bit of sugar. 

I'm going to look at the ingredients. The first thing is that there is a very long list of ingredients, and they're in very small type. I'm actually going to take my glasses off just to read them. 

I'm not going to read them all because it's pretty amazing, but it has dough conditioners containing one or more of the following: sodium stearoyl lactylate, calcium stearoyl lactylate, monoglycerides, calcium peroxide, calcium iodide, enzymes, whatever they are, monocalcium phosphate. I could go on. There's probably about 50 ingredients in total. I have no idea what they are.

I understand that these are what additives are. They are these things with strange chemical names at the end of the list of ingredients in a food. I don't understand what purpose they serve, how they affect my health. 

Luckily, I have one of the world's top experts on this subject with me today. Could you just start at the beginning? What are additives? 

Marion Nestle: Well, they told you what they are. Those are dough conditioners. You haven't mentioned the most attractive or unattractive feature of Wonder Bread, depending on how you look at it, was how soft it is. 

It's soft and squeezable, and it'll stay that way for a very, very long time. So one of the attributes of Wonder Bread is that it's soft; you don't have to chew it. You could practically just swallow it without mushing it around a bit, and it'll last on the shelf for a very, very long time. 

And that's commercial bread. So, commercial bread is full of additives that make it much, much softer. You don't have to chew it. Chewing apparently is a big issue when it comes to bread. A lot of people would rather just have this really soft stuff, and that's what they're for.

And these various chemical additives keep the bread fresh. They keep molds and bacteria from eating it. People like that. 

That company's been around for about a hundred years.

Jonathan Wolf: And so these additives aren't new, is what you're saying? 

Marion Nestle: It's not at all. They've been around forever. 

Jonathan Wolf: How are they discovered and produced, and how does that work? 

Marion Nestle: Well, companies discovered that if they put these additives in, then the bread would stay soft and last on the shelf.

The Food and Drug Administration in the United States didn't really get involved in that until the late 1930s, and all these things were in the food supply; people weren't dying on the spot. 

So by the late 1950s, they determined that the additives that had been around for a long time were Generally Recognized As Safe or GRAS, and they were out in the food supply. 

The idea was that if anybody could find anything wrong with them, they would take them out; otherwise, they were in. And that's pretty much been the attitude. 

There are probably 10,000 food additives in the food supply, at least I've seen that number. I certainly don't see 10,000 on food labels, but they have not been studied. Very, very few have undergone any kind of rigorous evaluation.

Then, since 1958, any new additives that came in, the companies that were using them were responsible for determining their safety and would appoint a committee. 

A committee would say, Oh, we reviewed the research on this, these things are fine, and send a letter to the FDA saying, These things are fine. But those letters were voluntary.

The FDA has other things to do besides worrying about food additives. It's concerned about general food safety, microbial food safety, and additives have never been a priority. 

Jonathan Wolf: So if I'm a company in the States and I want to add a new additive into my food… 

Marion Nestle: You appoint your own committee.

Jonathan Wolf: So basically, it's like when my daughter marks her own homework and says she's done an excellent job even though she clearly hasn't done an excellent job. 

In this case, I just select my own group of people to agree that this new additive is fine. And I send a letter to the FDA saying, I’ve done an internal inspection and decided this thing is fine.

Marion Nestle: You list all the references and send it. And occasionally the FDA has sent back letters saying, Hmm, we don't think so. But there haven't been very many of those, but they do exist.

But it's not something that is looked at with the kind of rigor that our new head of Health and Human Services, Robert F. Kennedy Jr., thinks is adequate. 

Jonathan Wolf: I am going to come to that maybe just in a bit and just understand more, I think, the situation here, and then look at the bigger picture, I guess, across the world as well. 

So firstly, the fact you're saying this with, I would say some sense of humor suggests that you think that these additives shouldn't just be viewed as clearly all safe, and you should not worry about adding them to your foods. 

Marion Nestle: Well, I'll say again, people don't die on the spot from eating these things, and it's very difficult to determine. 

I mean, how would you do the studies? If you think about it, if you wanted to rigorously evaluate every single ingredient on the Wonder Bread list of ingredients, that would be enormously difficult. You would need thousands of study subjects. 

These are really expensive, difficult studies to run. People eat lots of different kinds of foods with lots of different kinds of additives in them. These are very complicated scientific problems to address. They're really hard. 

I think everybody underestimates how difficult nutrition research is because humans are not experimental animals. You can't lock people up, do rigorously tested experiments in which you know exactly what people are eating, and wait for 30 years to find out whether the effects show, and additives are a minor consideration.

I mean, really, microbial food safety is a much bigger one in the FDA's list of things that it has to worry about. So it's been kind of ignored.

And this is, as I understand it, unlike the European precautionary principle in which the attitude is, if you don't know it's safe, you don't use it. We have the attitude that we'll use it, and if it causes problems, we'll get rid of it. 

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Jonathan Wolf: Could you talk for a minute about the contrast, for example, in Europe, about these attitudes to additives? 

Marion Nestle: Well, I suppose the color additives, since they're so politically important right now, would be the best example.

That is the red 40, blue 1 and 2, green whatever, and yellow 5 and 6 that are in lots and lots of candies, frostings, and kids' cereals that are marketed to children.

In Europe, these are not banned, as I understand it, but they are required to have a warning label. If you use them, you've got to say that there's some evidence that they might cause problems in some children, and in the United States, we just use them. 

Until now when, our new Secretary of Health and Human Services has made it his first priority to get rid of the color additives. 

And again, I'm laughing because why color additives? I could think of lots of other things that will make America's children healthy again. 

Jonathan Wolf: Tell me for a minute more about the Generally Recognized As Safe that you mentioned. 

Because it feels like that's part of this contrast around different approaches around the world, towards new additives, towards this idea that actually you need to justify in some way that this additive is safe before you added into food versus, I think you were describing something where you sort of assume it's safe until it's proven otherwise.

Could you help me to understand that? 

Marion Nestle: What the FDA is able to do is to revoke the GRAS status. It did that for trans fats, that is, partially hydrogenated salad oils that have fatty acids in a specific configuration that's different from the natural one. 

They revoked when enough evidence had come in that trans fats were unsafe and raised the risk for heart disease. The FDA revoked GRAS status on that. 

Once you do that, then companies really can't use it without being liable to legal interventions, and that took care of it. 

Jonathan Wolf: So when you look across this picture, it sounds like there's lots of reasons why food manufacturers would want to use these additives.

You described the Wonder Bread example. It makes the bread really soft, it lasts a really long time, all of these other things that are very attractive, both for the person buying the food, but also, I guess, for the manufacturer, for it to last absolutely a long time. 

And be cheaper. And I assume that cost is one of the elements, as you talk about using these, like red 40 and other things that are not used in Europe.

I think I've heard that part of this is to do with the relative cost, maybe of using that versus more natural colors. 

Marion Nestle: Well, I actually don't think cost is the main consideration, although it is a consideration. 

The main consideration is that the colors last much longer and are much brighter. They're much more vivid. And there's tons of research that shows that people think that brightly colored foods taste better. 

Jonathan Wolf: So basically, they can get a color that you just can't get from like a… because I think a lot of the colorants in Europe come from… 

Marion Nestle: Vegetables or spices.

Jonathan Wolf: Yeah, that’s right. So, if in Europe they're using plants and fruits in the U.S., with these examples like your red number 40, what does that come from?

Marion Nestle: Red 40? It's a petroleum dye, coal tar dye. These are coal tar dyes that have been in use for decades and decades and produce very, very vivid colors. 

Jonathan Wolf: And Marion, when you say it's a coal tar dye, sorry. Just help me to understand…

Marion Nestle: It comes from petroleum. It's oil. It comes from oil. It's a petroleum product.

Jonathan Wolf: You say that as though it's obvious. So they're basically putting bits of oil in the candy for my kids. 

Marion Nestle: Oh no. They're putting chemicals that are extracted from oil. 

Jonathan Wolf: Is that better? 

Marion Nestle: I have no idea. I have no idea. I never eat this stuff. So, I mean, for me, they're not something that are in my dietary plan at all.

If I see these colors on a package, I don't eat them well. I don't eat anything that's not natural. That's one of my food rules. 

Jonathan Wolf: So help me to understand a little bit whether anyone else should care. 

So we talked about these additives. You've already said there's a lot of them in lots of different places. They're not well studied because it's very hard to do this research. 

Is there any potential risks or downsides from this? Or is this like, Oh, that's sort of interesting, don't worry about it, carry on with your day. 

Marion Nestle: Well, the FDA has said that color additives are safe at the levels at which they're commonly consumed.

Other people disagree, and there have been a number of clinical trials dating back to the early 1980s when a physician named Benjamin Feingold developed the Feingold Diet, which was aimed at children with hyperactivity or neurobehavioral problems. 

His view was that if you took the color additives out of foods and didn't allow children to eat these diets that their behavioral problems would resolve, and it's been very difficult to do the science. 

First of all, you're not allowed to do experiments on children, so that's one problem, but there are others as well. 

The study with which I'm most familiar, because I know some of the people who are involved in doing that study, was one done in the 1980s on six children who were given either a drink that had color additives in it or a drink that did not have color additives in it. 

And somehow they matched the color of these two drinks so that you couldn't tell which was which. And neither the parents nor the children knew which was which. 

What they found out was that there was one child in that study who, every single time that child drank the drink with the additives in it, that child went off the wall and developed behavioral problems. The parents could identify it every single time. 

But the other five children, no, they didn't show any effects. So when the talk is about some children are sensitive, that's what they mean. Well, one out of six is a lot, or a little, depending on how you look at it.

So the behavioral problems are there for some children, and there are animal studies that indicate that some of these additives are carcinogenic in animals, or potentially carcinogenic. 

Well, from my standpoint, that's enough of a reason to get rid of them. You know, these things have no purpose in the foods other than to make people want to eat them. They're cosmetics. They don't have any safety function, they don't have a nutritional function. 

They are strictly cosmetic, and there are replacements. There are vegetable replacements, and they're not used in Europe, so on and on and on. They should have been gone a long time ago, so I'm happy that they're going to be gone.

A lot of companies have pledged now that they will get rid of the color additives by 2027. 

Jonathan Wolf: I feel like you've demolished these color additives. And on the other hand, we've gone from a general description of all of these additives that were in the back of that wonder pack to suddenly talking about the color additives.

But you also said, actually, this is almost like a small part of the conversation. There were so many other additives that were in that bread, and we're talking about why we might be concerned about all those other additives that are being put in our food.

Marion Nestle: Oh, we don't know what they do. You know, we don't know whether they're harmful. They're certainly there in very, very small amounts. Do small amounts make any difference with the color additives? 

I think the reason why the color additives come up so much is because they affect children, and because children are not eating one at a time, they're eating combinations of them. The idea is that a combination might be worse than eating one at a time. 

But you know, the chemical additives, they're chemicals of one kind or another. What they do in the body, you know, the prediction is that they're not particularly harmful. 

The FDA says that they're safe at levels commonly consumed, and how much you want to worry about this depends on what you want to worry about. I worry about other things more. 

Jonathan Wolf: Got it. So what you're saying is, there's a lot of different chemicals. I think you mentioned 10,000 different additives. 

Marion Nestle: That's what they say.

Jonathan Wolf: Probably each individual one, you are not saying that is really dangerous as an individual additive for me. But overall, do I want to be putting all of these different chemicals into my body that I don't understand what they do?

I'd probably prefer not to.  

Marion Nestle: Yeah, I mean, that would be my view. And I don't usually buy foods that have lots and lots of additives in them. 

Jonathan Wolf: I'd love to explore a little bit more than some of these particular rules, I guess, about what we do and don't put inside our food. 

The first one is cheese from raw milk.

Marion Nestle: They’re not banned. That's not banned in the U.S., only in interstate commerce. 

Jonathan Wolf: Help me to understand that. 

Marion Nestle: It's not banned. You could buy raw milk cheeses in the U.S. In fact, you can buy European raw milk cheeses in the U.S., very good ones, actually, as long as they're aged for a certain amount of time.

Jonathan Wolf: You can buy exactly the same.

Marion Nestle: Well, I'm not sure they're exactly the same, but we certainly have European raw milk cheeses available at cheese stores in the United States. 

There's a very good one, very near where I live. 

Jonathan Wolf: I'd understood that if they hadn't been aged for a certain period of time…  

Marion Nestle: Well, they have to be aged.

Jonathan Wolf: Okay. Which is different. So there's a difference there, an assumption about what is safe.

So there are a lot of cheeses, I understand that I could buy here or when I'm in Paris, that I couldn't buy in the U.S., just as an example. 

I'm curious, is this showing you that the complexity of deciding what is safe? How do you understand that?

Marion Nestle: Well, safety is relative. What do you mean by safe? 

The problem with raw milk is that some raw milk is contaminated. Not all, some raw milk is contaminated with extremely lethal bacteria that can make you sick or kill you. 

The pasteurization takes care of that. And a lot of people feel very passionately that raw milk cheeses and raw milk products taste better and are better for you than pasteurized. 

Fine, they're taking a risk. How big a risk, very hard to say. 

Jonathan Wolf: You've described a situation where you can add all of these additives in the states and the company decides itself, and as a consumer, I'm left to navigate that. 

Whereas this situation with the raw milk isn't permitted, and you see a situation maybe in another country, let's take France, for example, where this is sort of backwards, the other way around. 

How much has all of this been driven by, I guess, medical evidence and trying to do the best thing for us as consumers, and to what extent has it been affected by lobbyists and manufacturers and things like this?

Marion Nestle: Well, all of that is involved, but if you're a food manufacturer, you don't want to kill your customers. I would think that's not good for business. 

I once visited a raw milk factory, if that's what it is called in Italy, and they were making a soft white cheese, and we could see the people up to their elbows dealing with this milk that was in the process of being curdled, and it didn't look very sanitary, and everything was open.

And afterwards I asked as politely as I could, Do you test for e.coli or Listeria? And they gave me a list that was pages long of everything they tested for. They were so scrupulous about what they were doing and what they were producing, and so careful about making sure that their cheeses didn't have these lethal bacteria that I thought, Oh, I'd eat that one.

But you have to know the producer. You have to know the producer in that situation. And if you don't know the producer, you have to rely on the government to have rules so that you're not going to be eating something that's going to make you really, really sick or kill you. 

Jonathan Wolf: I love this example because I think that, you know, I have quite a few French friends. I once worked in a French company. 

And for them, the idea that these sorts of cheeses that they've grown up with and that I think they would say have been part of their culture for thousands of years are in any way not safe, sort of seems mad. 

So is this partly to do with what we're used to and the extent to which perhaps, and I think particularly about maybe the U.S. and the U.K. where we've been very separated from our food culture for a very long time and tend not to have the same strength of a food culture as you often see in many other parts of the world. Not just in Europe, but the same in Asia. 

And that somehow the very industrialization makes us feel safe. So you've talked about the bacteria, there's definitely no bacteria, and also you stick in all of these additives in order to make sure that it sort of stays safe.

But we’ve then ended up with these foods, which are incredibly unnatural and potentially causing a lot more harm than the thing we're trying to avoid in the first place. 

Marion Nestle: Oh, that's possible. The whole question of food safety is one of risk. 

Risk is a very complicated concept. It's very difficult for people to understand because you're dealing with probabilities. You're not dealing with certainty. 

So the probability of becoming ill from eating a raw milk product, usually, I mean, if the cheeses are aged, then the probability goes way down. But the probability is greater of becoming ill from consuming raw milk than pasteurized milk. How much greater, difficult to answer.

And the science in all of this is very complicated, in part because people eat such complicated diets, and they're not the same every day for most people. 

Jonathan Wolf: If I now flip the other way around, we've talked about the sort of food colorings already. You've rather shocked me with the fact they're literally made out of byproducts of petrol.

Marion Nestle: It doesn't sound very attractive, does it? And if you look at the chemical structure of the molecules, they don't look very attractive either. 

Jonathan Wolf: But I understand this is not the only additive still allowed in the U.S. that are not allowed in a lot of other countries, and we talk about Europe a lot, but I think it's going to be similar elsewhere.

I understand there are a number of other additives where there's a very different view about that risk reward. Are there any that you'd be able to?  

Marion Nestle: I don't think I know any offhand, but if you have some, you can tell me what they are. 

Jonathan Wolf: Well, one that was mentioned here is like brominated vegetable oil. 

Marion Nestle: Oh yeah. I think it's on the list of things that people want to get rid of. 

The state of Texas has passed a law that forbids 44 separate additives in the food supply from being allowed in Texas Foods. That will have a big effect because companies can't formulate different products for different states.

And so Texas has sort of taken the lead on that, and I believe that's one of the things that was in there. I'm not sure that's true, I vaguely remember. It was a long list. 

Jonathan Wolf: Yet what's interesting, I think you said, is there's a long list of did you say 46, but you're also saying there's sort of 10,000 of these ingredients that are out there.

Marion Nestle: Well, I can't imagine where the figure 10,000 comes from, because you certainly don't see 10,000 additives listed on food labels. 

Jonathan Wolf: So that would be a significant reduction in the number of additives that are… 

Marion Nestle: The Texas 44? Oh, that would knock everything. Most of the ultra-processed foods out of the food would be knocked out of the food supply.

Jonathan Wolf: So that would be quite a profound shift to what you're allowed to eat. 

Marion Nestle: Oh, it would be huge.

Jonathan Wolf: How do you feel about that? 

Marion Nestle: I think it's fun to watch. I find all of this extremely entertaining. Because food advocates like the advocacy group Center for Science in the Public Interest have been trying to get color additives out of foods for decades and have made no headway. They're considered kind of a left-wing organization. 

Now it's Republican right-wing states that are taking the lead on doing this. And so that's kind of head-turning, and you know, I don't know what to make of it. It's just astonishing to me. 

Jonathan Wolf: Part of what astonishes you is the shift in terms of who's pushing right to remove these advocates.

Marion Nestle: It's astonishing. I hardly know what to make of it.

But let's get rid of them, you know, we’ve been trying to get rid of them for decades. It's time. 

Jonathan Wolf: Why has it been hard to do this sooner? 

Marion Nestle: Oh, because the food companies say they can't exist without them. Even so, the candy companies are just stunned.

They have tried. It's not for lack of trying. Mars at one point said it was going to get rid of all of its petroleum color additives, and it didn't. It couldn't do it. It couldn't find replacements that had the bright, shiny colors that people expect in M&M's.

General Mills, a cereal company in the United States, tried to take the color additives out of Trix cereal, which is a cereal designed specifically for children. And the colors were kind of brown and tan and fall colors, I thought rather attractive fall colors, but I'm not four years old, and nobody bought the cereal. They stopped buying it. They said it didn't taste as good. 

This is color psychology in food. 

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Jonathan Wolf: And that this really makes a difference to children buying these candies.

Marion Nestle: Everybody thinks the brightly colored foods taste better. 

What you want is you want a level playing field as there is in Europe. There's a level playing field on color additives. Everybody's got to do the same thing, so then the companies can continue to compete. 

But in the United States so far, all of this is voluntary. It's voluntary for the end of 2027, so it's not exactly going to happen tomorrow. But a lot of companies have said they will voluntarily remove them. 

Jonathan Wolf: Do you feel that this new political pressure coming from the new American administration is really going to shift the field on all of these additives, or is this very much around the colorant additives specifically? 

Marion Nestle: Well, they started with color additives. I think there are others. I think it's too soon to tell. 

Jonathan Wolf: We've talked a lot about additives that are put in for the end consumer experience. So the colors we've talked a lot about. You've also talked about sort of the shelf life and the softness.

But one of the things that the team also shared with me is that there are a lot of additives that are used in the farming processes in the states that might not be allowed elsewhere. 

So I'm thinking about what is it that you are allowed to feed your animals, for example, that then sort of goes upstream into what we might end up eating.

Should we worry about the stuff that wouldn't appear on my food label because it'll just say beef or pork, but are effectively all the things that have been fed to these animals to affect their growth? 

Marion Nestle: Well, the big question in animal feed is antibiotics, which have an enormous impact on the health, not only of animals, but also of people.

There have been pressures for, again, decades to try to stop industrial animal producers from using antibiotics as growth promoters because they work as growth promoters. 

I mean, everybody is fine about giving antibiotics to animals if they're sick and need them, but the idea that you would just routinely across the board put antibiotics in the feed of animals in order to get them to grow better and not get sick because they're so closely raised together. 

Hundreds and thousands of animals are raised together. That's been a huge issue, and it's been impossible to deal with because the meat industry says we need this. 

Jonathan Wolf: Marion, could you tell us a little bit more about why they're using antibiotics for something other than just stopping them from getting sick?

Marion Nestle: If you want to be efficient about meat production, you have large numbers of animals raised together in very closely confined animal feeding operations.  They're called CAFOs. 

The animals are messy; they don't use toilets. So you have a lot of mess. And if one animal is sick and has some bacterial disease, it can easily be transmitted to all the others that are mucking through whatever they're mucking through.

And so if you put antibiotics into the feed, it does two things. It not only prevents the animals from transmitting bacterial diseases from one to another, but it also, for reasons that are quite poorly understood, nobody really knows why, it encourages the animals to grow more rapidly.

If you can raise animals to grow more rapidly, you don't have to feed them as much, and that saves cost. The object is to produce meat at as low a cost as possible so that you don't have to charge too much for it, so everybody will buy it. 

Jonathan Wolf: So you pump them full of antibiotics. Which I think we know from many other podcasts we've had here, obviously, deeply disrupts your gut microbiome.

And then these animals end up just putting on a lot more weight faster than they would without these antibiotics. 

And so is that a standard part of farming practice now? 

Marion Nestle: Yes. 

Jonathan Wolf: And so you brought this up, why, as a consumer, might I care about this? 

Marion Nestle: Well, if these antibiotics are antibiotics that are used in for human diseases, they're not going to work because they will have selected for bacteria in either the animal's microbiome or yours that will resist these antibiotics, and the antibiotics won't work.

And you know, lots of antibiotics are confronted with resistant bacteria now. And this has made the antibiotics much less useful for treating human disease. 

Jonathan Wolf: Can these antibiotics make their way into the food that we eat? 

Marion Nestle: That's hard to know. I mean, yes, they would be incorporated, but they would probably be destroyed, or you would think that it wouldn't make any difference, but apparently it does, and partly because the animals and humans share the same bacteria in some ways. 

And so the workers on the industrial farms, on the industrial CAFOs, carry the bacteria from the animal's home; those bacteria infect humans, and they get transmitted that way. So it's not that it's in the meat, it's in the bacteria. 

Jonathan Wolf: Got it. One of the things that people living outside the U.S. talk about is sort of the higher level of industrialization of these sorts of things.

So antibiotics in the feed is one. Chlorinated chicken is something that comes up all the time in the United Kingdom. I'm not sure if anyone in the U.S. even hears about the concept of a chlorinated chicken. 

Marion Nestle: I think we chlorinate all of our chicken. So I think you chlorinate all of your chickens. 

Jonathan Wolf: These chlorinated chickens are banned in the U.K. and the E.U. 

Marion Nestle: Well, we have to talk about Salmonella. I mean, here's another one. 

An enormous percentage of supermarket chickens in the United States are found to be contaminated with Salmonella, often toxic Salmonella, which, if ingested by humans, would make people sick.

The Department of Agriculture has argued forever that Salmonella is normal in chickens and therefore doesn't need to be labeled, and you don't need warning labels. 

And we have warning labels now, but it's been extraordinarily difficult to get those warning labels onto the chickens to make people understand that if you've got a chicken in your house, you've got to deal with it as if it were you were running a contamination laboratory.

You really need to wear gloves, and you shouldn't handle these, and you certainly don't want to wash them in your sink because the bacteria from the chicken are going to get on your dishes and everything else. 

And for decades, I mean, these are old issues. Food safety advocates have argued that Salmonella should be considered an adulterant on chickens, and if it's an adulterant, you can't sell it.

But the poultry industry has successfully managed to keep that one off. 

Jonathan Wolf: It's amazing, right? This tension you keep coming back to between what might be optimal for the manufacturers making this, is not always what's optimal for us as consumers. 

Marion Nestle: Oh, it's an enormous problem. 

Jonathan Wolf: Apparently that the team said that on chlorinated chicken, what the European commission has said is that the reason why they're concerned about it is that chlorine rinses are a way to sidestep animal welfare standards earlier in the process.

So they say it's a way to clean this away, and therefore, you sort of hide, I guess, not looking after this as much earlier. 

Is this again a sign that I think we know that lobbying by big food companies is an issue around the world, that it's somehow even stronger and more perfected in the States than in a number of other places?

Marion Nestle: Yeah. The lobbyists are really good at what they do. They're paid to make sure that no federal agency passes regulations that are going to raise their costs or make their lives more difficult.

They're paid to do that, and they're very good at what they do. Consumer advocates have a much greater difficulty because there are very few consumer organizations that pay lobbyists to try to counter some of this.

Right now, it's hard to talk about, but there's always been this tension between the health of consumers and the economic health of the corporations that are producing the food. 

There are real tensions about this. From the corporation's standpoint, keeping the cost of food low is something that's very important. It means everybody can afford it. It means they can hire people. They've got jobs, they've got places where they're supporting entire communities because everybody in the community works for one of these places. 

These are very important considerations in the states. 

Jonathan Wolf:  I think anyone listening is not who is outside the states is not going to say this is totally different where they live. It's just like a matter of degree, it seems to me. 

I think the thing that I think of as you describe the cheap food and the availability, which I think has always been a very powerful argument, is listening to this now in 2025, it's now clear how huge the unexpected health costs have been for all of us.

Of eating these very highly processed foods with all of these different things in them, so far away from the sorts of foods we used to eat. 

So when you think about those lost years of healthy life. The diabetes and the heart disease, and the raised cancer rates, and all the rest of it. When you put that in alongside the fact that your bread is 20 cents or 20p or 20 euro cents cheaper. 

It's not cheaper at all, is it? It's actually more expensive. 

Marion Nestle: Well, those are the externalized costs. 

Jonathan Wolf: Help me to understand. 

Marion Nestle: It's an economics term, but I love it. It's the externalized cost of producing food in the health consequences and in the cost to the environment, which is a whole separate issue, that the companies don't pay for the healthcare that people have to have later on, and they don't pay for the environmental cleanup. 

I mean, the obvious example there is that the big agricultural production in the United States is in the Midwest, and the chemicals that are used to grow corn and soy beans are used in great excess.

They get into the water supply, they flow down the Mississippi River, and they end up in the Gulf of Mexico, killing all the fish in the Gulf of Mexico, or stimulating the growth of plants and algae so that the fish don't have enough oxygen. 

That's an externalized cost of agricultural production, and probably the most obvious example. 

Jonathan Wolf: How should this affect what I think about what I eat?

Marion Nestle: Well, I think diets are simple. 

What a healthy diet is is so simple that the journalist, Michael Pollan, can do it in seven words: Eat food, not too much, mostly plants. And that takes care of it. And within that structure, once you define food as something that's minimally processed, that's all you have to do.

But what that does is to exclude the most profitable processed foods that are on the market. And those are cheaper because if you make a bread that lasts on the shelf for a long time, you could sell it at a lower cost. You're not constantly having to replace, you're not wasting a lot.

When these foods are designed to be really tasty, people love them. Everybody has their favorite breakfast cereal, candy, cookie, biscuit, whatever, or bread for that matter. 

These are deliberately formulated to be irresistibly delicious. Some people are talking about addiction to specific food products. That they stimulate the same kind of dopamine responses that addictive drugs do. Whether that's true or not remains to be determined.

But a lot of people feel that they're addicted to certain kinds of foods. And a lot of addictive scientists say that they meet the criteria for addiction. I'm not sure, but there's a lot of talk about that these days. 

Jonathan Wolf: Saying to avoid all processed food or only minimally processed food is really hard.

Marion Nestle: Oh, I would never say that. I would say minimize. 

Jonathan Wolf: I think it's hard for yourself. It's even harder when you have a family and you think about, you know, your children and the sets of choices. 

Marion Nestle: Well, remember that those food manufacturers are deliberately marketing their products to your children. 

Jonathan Wolf: Tell me a little bit more about that.

Marion Nestle: Well, the objective is to get children to like certain foods because they're going to eat them through their entire life. 

Marketing is aimed at children, and even though children don't have money of their own usually, they certainly have the ability to… actually, it's called the pester factor. They have the ability to nag their parents to buy certain foods for them, and companies deliberately advertise to this, and they do this on social media that the parents never see.

So it's invisible to most parental authority. I mean, I don't have young children anymore, but I have friends who do, and they say, We've never taken our child to McDonald's. We don't have McDonald's food in the house. When we drive down the street and my child sees a McDonald's outlet, my child says, I want to go there. Take me there. 

And when I say, Why? The child doesn't really know, but the child wants to go. That's brilliant marketing. 

Jonathan Wolf: That's interesting. 

Marion Nestle: It’s fabulous.

Jonathan Wolf: And you feel that they are intentionally focused? This isn't like a byproduct. 

Marion Nestle: There’s research that shows that they're intentionally doing it.

Jonathan Wolf: There's real research that says they're intent… 

Marion Nestle: Absolutely. Because they're trying to sell products. 

Food companies are not social service agencies. They're not public health agencies. They're businesses. They have stockholders to please. That's their job. They could be selling widgets. Their job is to sell more to as many people as possible; the consequences are irrelevant. 

I think we need regulation. That's what government is supposed to do. The executives and food companies have told me, We would like to do the right thing, but if we do the right thing, our competitors are going to get ahead of us. 

We need a level playing field. The only way they're going to get a level playing field is if the government issues regulations.

That's why I'm in favor of government regulations. I think it's better for consumers, but it's also better for the companies because they're not going to be competing with each other in ways where they shouldn't be competing with each other. 

Unfortunately, there are many examples of companies that have not behaved with much integrity when it comes to food safety. There are plenty of places that do, but there are plenty of places that don't. And for that, we need government regulation. 

I mean, maybe this is the case in the States more than in other countries, but certainly in the States, it's a huge issue. 

Not to have government regulation means that companies are given permission to behave badly.

Jonathan Wolf: I actually think the rest of the world might be getting a slightly light ride out of this conversation, Marion.

I do think that things are worse in the States than in many other places, but we have the same explosion of obesity and diabetes, all these others, like impact on mood, all these other things that are going on, and the same explosion of very highly processed high-risk foods.

So, although I think there are more controls in a number of other developed countries. The same underlying pressure, the same pushback, I think that we see from big food companies about any restrictions on the advertising they do or the way in which they process their food. 

There's a global tension here, it seems to be, and visiting lots of different countries and seeing this. 

Marion Nestle: Well, we have corporate capture of government these days, pretty much worldwide, and I don't think that that's necessarily for the public good. 

Jonathan Wolf: So, if I could give your magic wand now and you could suddenly reset the regulations around the world, what would be the top things that you would want to change? 

Marion Nestle: Well, it depends on what country we're talking about. 

Jonathan Wolf: It applies everywhere, 

Marion Nestle: Everywhere? Get money out of politics would be my first one. 

But I would say put regulations on marketing to children. I think it's morally wrong because children really are not in a position to exercise judgment over this.

There's plenty of research that shows that kids can't tell the difference between advertising and content. And require media literacy in schools so that children learn how to distinguish advertising from content.

So I would start there. In the States, I would deal with school meals in a much more direct way. They need much more money for the meals. They need much better food. 

But, maybe, maybe the states have particular issues 

Jonathan Wolf: On school food, what would be the top thing you'd want to change?

Marion Nestle: Oh, I would rather have kids eat real food than packaged food, real food, the way the French did or do, or still do? 

Real meals that are cooked with the expectation that children will eat the food, taste the food, and get involved with the food. 

I think school food is enormously important because again, in the States, there's evidence that shows that kids eat most of their calories in schools, and their healthiest calories in schools, though. 

So it's important that schools do it right. 

Jonathan Wolf: And when you think about any regulations that might affect the food that we eat as adults… 

Marion Nestle: Well, I'd like to see restrictions on ultra-processed foods, portion size considerations, and people have to find ways to eat healthfully and pleasurably without taking in too many calories for their activity and metabolic levels. 

Very difficult to do for most people, obviously, which is why so many people are overweight and kids are overweight now in a way that they never used to be. 

Part of this is dealing with the social media problem, which is an enormous one. I'm so glad I don't have small children now. I think it would be so hard. I raised my children before social media. Life is really tough for parents now. I have enormous sympathy. 

Jonathan Wolf: I think that's really nice. I have a 17-year-old and a 6-year-old, and there are a whole set of pressures that you worry about, I think, as a parent of things that like the access to these digital devices and what's really going on in their lives that my parents never had to worry about because it didn't exist. 

Marion Nestle: Yeah, and you don't want to argue with your kids about food. When you have so many other things to argue with your kids about.

Jonathan Wolf: Correct.

Marion Nestle: I’m guessing, 

Jonathan Wolf: Well, in my house, we’re all stuck with it. We talk about food a lot, and the thing that's been transformational in my house is this shift of thinking about eating this food not just generically because it's healthy, but thinking about you've got all of these trillions of good bugs in your gut, and if you're eating the right things for that, you're feeding them. 

I have found that that is a real unlock because it's about adding things. It's not about making some particular food being demonized. But still, as you've described, as soon as you go out into the world and you can just walk into a store and there can be literally nothing in there that you really feel you want...

Marion Nestle: To feed your bacteria. 

Jonathan Wolf: Exactly. And so that is definitely a problem. 

Marion Nestle: Well,  the wonderful thing about it is the ‘eat food, not too much, mostly plants’, it applies not only to feeding your microbiome, but it also applies to obesity, heart disease, type two diabetes, cancers. I mean, it's so simple, and it's one diet.

There are also an infinite ways of putting foods together to eat that way. So it's not as if it's boring or restrictive. I think of it as opening lots of ways of thinking about this that are extremely pleasurable. 

I worry a lot about losing the pleasure of food. GLP-1 drugs, for example, people report that they're not interested in food anymore. That breaks my heart. 

Jonathan Wolf: I love that, and maybe actually we could wrap up. So let's say I take your magic wand away. I'm sorry, Marion, but you know, you had it for five minutes, but now I've taken that magic wand away, and all you can do now is actually just give individuals advice.

You've given this sort of very high-level: try and eat minimally processed food, but not too much. But people saying, Okay, help me to understand a bit more about how I might think about applying that to my life in quite a practical way without losing the joy. 

What would a great lunch and breakfast be for you? 

Marion Nestle: First of all, I'm not a breakfast eater, so I don't get hungry until later in the day, but I'm perfectly happy to have something made with vegetables or fruits or grains.

I'm perfectly happy. I'm not a vegetarian. I'm not a vegan; I eat everything. I try to follow my own advice, and I don't have to work very hard doing that; it comes quite easily.

For people who are raised on processed foods, getting them to eat other kinds of things is very, very difficult. And I would never tell anybody, do this, do this. I would try to find out what they're willing to try and what baby steps they're willing to take, and then work with them. 

But that's an enormously difficult job. People who are used to eating one way don't want to change, usually unless they have to, or a doctor tells them to.

Jonathan Wolf: Well, Marion, I hope I'm not going to about to get an enormous amount of trouble from you, but I'm going to say that you are into your eighties, and you are…

Marion Nestle: Well into my eighties. 

Jonathan Wolf: Well into your eighties. And for anyone who's not on video,  you're in incredible shape, but you're also razor sharp, and you've kept me on my toes a lot through this conversation, a lot more than normal. 

A lot of listeners are thinking about what they eat, bluntly, to be in the shape that you are in right now when you know they're 89. What do you put that down to? 

Marion Nestle: Good nutrition. I don't know. I can't say good genes because my father died of a heart attack at the age of 47.

So, maybe it's genes, maybe it's luck, maybe it's eating healthfully, which, as I said, that's how I like to eat. 

Jonathan Wolf: And this isn't just a recent discovery. 

Marion Nestle: It’s how I've always liked to eat since I was a child at summer camp and discovered a camp that I went to had a vegetable garden for dinner. We were sent out to pick the vegetables that were cooked for dinner, and I realized how absolutely delicious fresh vegetables are.

It's what I've liked ever since. And I don't like a lot of junk food, and I do read food labels on packages, and if it's got all that stuff in it, I leave it on the shelf. 

Jonathan Wolf: I'd like to stop there because I don't think there's anything better that I could ask. 

I'd like to do a quick summary, if that's all right. And correct me if I've got anything wrong. 

So the first thing that honestly jumps into my mind is that these U.S. food colorants come from oil, petrol, or gas, depending upon the country. This is totally mad. 

It's really shocking that the big food companies in America have said for decades that they can't exist without these additives because if one company takes it away, then all the other companies keep it, and so they will lose their market share. 

So there's this terrible pressure to keep putting these bad things in. We're finally starting to see some real pressure to remove those particular additives. But the general environment in the States continues where any company can just add a new additive, declare that it's safe, and just put it into the food.

And there are potentially thousands of these. We don't understand what they do because doing the studies on these individual editors is so hard. So this just feels sort of backward that anyone can put this in, and if they put it in, then all the other companies feel they should put it in. So this is a really profound problem.

It is better in Europe in regard to having to prove a lot more that something is safe, but still, we have this incredibly highly processed food and all of these different additives that we don't understand. 

We talked a little bit about what's going on, also, in the animals that we end up eating. Because you don't necessarily see this directly in your food labels. 

For you, the top thing was the antibiotics that, amazingly, they're giving these animals all of these antibiotics, and it's making them really fat. Which I think begs the question of the fact that so many of us end up having 20 courses of antibiotics before we're grown up, and how that might be affecting our health.

But that's probably a whole other podcast I'd love to talk about, and that this ends up then flowing through to what we eat. 

And for you, there's two parts of this. One is that we need more regulations, and that the lobbying of those big food companies around the world is incredibly powerful.

Interestingly, for you, the first thing you went to is about marketing aimed at children. They are intentionally understanding how to make their products as attractive as possible to kids. And you gave this brilliant example of a child knowing about McDonald's, even though their parents had never taken them to McDonald's.

Think about school meals as something that could get children to eat real food? And how important that could be for their health, and really restricting this ultra-processed food. What we tend to call sort of high-risk processed food, if a nutritional scientist at ZOE tells me off for the vagueness of ultra-processed food.

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Then you talked about what could individuals do, and you said that if you're going to boil it down to like a really simple sentence. I got: eat minimally processed food, not too much, mostly plants. 

Read the food labels, so turn it over and understand what's in there. And a lot of listeners are ZOE members, and they know that's one of the things that the app enables you to do, is short-circuit that.

If you end up like Marion on the back of eating all of this food in your late eighties, I think you're doing something pretty amazing. So you're definitely a walking advertisement for the power of what we eat in terms of giving us a really high-quality life. 

So thank you so much for coming in. I thought that was like really powerful. 

Marion Nestle: Well, thank you very much.