Beyond The Health Panic Of “Ultra-Processed” Food — Here’s The Science, And What Experts Will Never Eat

Updated May 27, 2025 at 5:30 p.m.*

HAMBURG — Fish sticks, candy and ready meals may be convenient and tasty — but they’re often far from healthy. So what does the research really say about “ultra-processed” foods and what goes into them? And what exactly does that term even mean? Die Zeit asked four experts (specialists in nutritional medicine, neuroscience, food chemistry and other related disciplines) for their scientific opinion.

“Potato chips don’t alter my consciousness.”

Johannes Hebebrand is head of the Department of Child and Adolescent Psychiatry at the University of Duisburg-Essen. One focus of his work is eating disorders.

The idea of food addiction — i.e., compulsive overeating of highly processed foods — has been around for a while now. Lab experiments have shown that rats can develop a craving for sugar that looks a lot like craving for cocaine. But I’m not convinced. What’s missing is solid evidence that certain substances in processed foods actually act on the brain to produce intoxication and addiction. Yes, these foods activate the reward system — but so do many other things in life.

Of course, many people know what I’m talking about: you open a bag of chips in the evening and it’s a miracle if you stop before it’s empty. But is that addiction? Or is it because the food industry precisely targets the tastes of certain consumer groups that people go for those products? It works with sugar, salt, flavor enhancers and additives.

There’s another issue, too: when you take a drug, you usually notice an effect right away. Giving me potato chips doesn’t alter my consciousness.

We know the body fights hard against long-term weight loss.

Why do we eat so much of this stuff? Well, if you’re overweight — which is the case for many — you have to take in a lot of calories just to maintain your weight. So you could say: if I’m obese, I need high-calorie food. We know the body fights hard against long-term weight loss.

It would certainly make sense to regulate the food industry to reduce consumption of these intensely flavored products. Some countries are trying to make unhealthy food more expensive. In Germany, almost nothing has happened so far. In the U.S., people even compare it to the tobacco industry, which kept pushing people to smoke, and they believe the food industry could eventually be forced to change. But since it’s unclear whether ultra-processed foods are truly addictive — unlike nicotine — the food industry can easily dodge accountability.

You could also ask: is food addiction actually a behavior not tied to any specific substance? People who say they’re addicted don’t always eat the same thing: That’s why we advocate classifying food addiction as a non-substance-related addiction. Of course, we would need to define what that means and distinguish it from other disorders like binge eating.

“What and how we eat was intentionally designed.”

Alexandra DiFeliceantonio is a neuroscientist at the Fralin Biomedical Research Institute at the Virginia Tech Carilion School of Medicine in the U.S. She co-directs the Center for Health Behavior Research.

I’m interested in the signals that highly processed foods send to the brain. Foods that contain more sugar, fat and salt tend to attract us more. The composition is crucial. But there are likely additional effects too. Some industrial processing methods can’t be reproduced in a home kitchen — extrusion, for example, where a food mass is pressed into molds, or high heat or the extraction of starch… We don’t yet know what all of that does.

Almost 60% of the food consumed in my home country, the U.S., is highly processed. And I’m absolutely convinced that this is not something individuals can solve on their own. Fresh food has to be accessible and affordable, and that requires government subsidies. Just because processed foods are everywhere doesn’t mean we shouldn’t take action. They’re not inevitable.

The food environment we live in was designed deliberately. In the U.S., for example, tobacco giant Philip Morris bought food company Kraft in the 1990s, and other tobacco firms have done similar things. And I know I sound like I’m wearing a tinfoil hat when I say this, but they’ve used the same strategies they once used to get people hooked on cigarettes to promote and sell sugary drinks and foods. The food system we have today wasn’t designed for our health. It was designed for profit.

“It is a misconception that everything you cook at home is healthy.”

Monika Pischetsrieder heads the Department of Food Chemistry at Friedrich-Alexander University in Erlangen-Nuremberg. She is a member of the Scientific Advisory Board for Agricultural Policy, Nutrition and Consumer Health Protection at the Federal Ministry of Food and Agriculture.

I can sum up the problem in one sentence: you have to differentiate. Processing or a long list of ingredients is not automatically what makes a food unhealthy. It always comes down to the composition, to the ingredients. And we actually know very well what’s healthy and what’s not. The concept of ultra-processed food is just old wine in new bottles. Demonizing processing itself has no scientific basis.

Take a package of organic hummus with grilled vegetables. It has 14 different ingredients, but they’re all high quality. Now, compare it to a strip of bacon. That’s two ingredients: just pork and curing salt. But that’s a much less healthy choice. There’s also a false belief that whatever you make at home is automatically good for you — but there’s a big difference between cooking fresh vegetables and baking a cream cake.

What I’m saying is, there’s no shortcut here.

Some processing is explicitly beneficial for health: heating and pasteurizing raw milk can save lives by killing listeria. Some foods are only edible after processing — you can’t eat whole grain kernels.

What I’m saying is, there’s no shortcut here. We have to go the long way and assess every product and every ingredient on its own. At the same time, it is absolutely possible to eat a healthy diet: lots of fiber, plenty of fruits and vegetables, legumes, very few sweets, and ideally no soda or alcohol.

“You hardly have to chew a soft burger bun.”

Anja Bosy-Westphal is a nutritionist and nutritional physician. She leads the Institute of Human Nutrition and Food Science at Kiel University.

There’s no doubt that eating highly processed foods is linked to obesity. What I want to understand is: why do we eat so much of them? Because we’re dealing with an obesity pandemic that we just can’t get under control.

Today’s foods often contain ingredients that have been processed multiple times. Take starch, for example. You’re just extracting the carbohydrates from the grain, leaving out the fiber. That means fewer valuable nutrients. You’re also losing things like secondary plant compounds, which support the microbiome, or vitamins, minerals and trace elements.

Another big factor with many of these foods is how easy they are to eat — you barely have to chew them, like a soft burger bun. And they taste great. Flavorings contribute, as do sweeteners and of course salt. Chips are especially tempting because they’re crunchy. Studies show that the softer and tastier the food, the more spontaneously people will eat it.

You should be able to buy something healthy from a vending machine at the train station.

But there’s still a lot we don’t know. We need more insight into how processed foods might affect things like inflammatory bowel disease. Specific ingredients such as emulsifiers or sweeteners could negatively impact the microbiome — those are areas where more research is definitely needed.

Fundamentally, we need to rethink the food environment. In supermarkets, healthy choices should be placed at eye level instead of junk food. You should be able to buy something healthy from a vending machine at the train station. I also see potential in institutional catering. A lot of kids eat at daycare, adults at work and seniors in care homes. Healthy meals need to be more affordable and more appealing in those settings.

*Updated May 27, 2025 with enriched media.