Nutrition: How bad are highly processed foods really for our health?
For many, they are pure poison: highly processed foods. And in fact, many studies suggest that they can be detrimental to your health. However, when most people think of industrially produced foods, they think of teeth that have become decayed due to cola and overweight children who stuff themselves with nuggets, but not of the supposedly healthy plant-based alternatives for meat, cheese or milk and certainly not of whole grain bread. Rightly so?
The category of highly processed foods and drinks (ultra-processed foods) includes all those where many work steps are necessary in the processing of the raw materials. In addition, according to the Federal Center for Nutrition, they “usually contain plenty of additives, energy (calories), table salt, saturated fats and sugar, but little fiber, vitamins and minerals.” These additives are added, among other things, to make the product more durable, tastier or visually more attractive.
Typical products include margarine, sausages, fried snacks, spreads, ready meals, ice cream, chocolate bars, carbonated soft drinks and plant-based substitutes. Or to put it another way: many. Around 20 years ago, around half of the energy intake of adults in Germany came from highly processed foods, according to calculations.
At the same time, there is increasing evidence that high consumption of such products can pose a health risk. Most of the information on this comes from observational studies. A review study published in February 2024 identified 32 health problems that have been linked to highly processed foods, including cardiovascular disease, type 2 diabetes and mental illnesses such as depression.
There is enough criticism of highly processed foods. However, there is still little conclusive evidence. The researchers criticize, among other things, the low nutritional value, but also the formation of potentially toxic compounds. “Another point is that a high intake of additives such as emulsifiers and artificial sweeteners is said to promote inflammation in the body,” says the Federal Center for Nutrition. In addition, highly processed foods have a kind of addictive factor, which is sometimes due to the combination of carbohydrates, fats, sugar and salt and leads to excessive consumption. The phenomenon is known from chips, for example.
How exactly can you tell what is a highly processed food and what is not? Brenda Davis, professor of nutrition at Virginia Tech, gave a simple explanation to the New York Times. She says: "If you see things on the ingredients list that you wouldn't use in your home kitchen, it's probably a highly processed food."
But not all of these foods should be viewed equally in terms of health risks. There are differences. This is shown by the results of an observational study that was carried out in the USA between 1986 and 2018 and involved more than 100,000 people. It showed that the people who ate the most highly processed foods had a four percent increased risk of death. However, this correlation does not apply to all highly processed products, but rather to a subgroup, as the lead author of the study, Mingyang Song, explained to "CNN". “Including processed meat and sugar-sweetened or artificially sweetened beverages,” says Song. He recommends avoiding such foods or at least limiting their consumption.
However, Associate Professor of Clinical Epidemiology and Nutrition at Harvard's TH Chan School of Public Health doesn't believe in demonizing all highly processed foods: "Grains and whole-grain breads, for example, are also considered ultra-processed foods, but they contain various beneficial nutrients such as fiber , vitamins and minerals."
The Food and Agriculture Organization of the United Nations advises limiting consumption of highly processed products. Professor Mingyang Song also thinks this is sufficient. In his opinion, the holistic view of a healthy diet is crucial. He says: "If people eat healthy in general, I don't think they need to be afraid or freak out."
Most of the evidence regarding ultra-processed foods and health comes from observational studies. These can be considered meaningful due to the size of the participants and the duration of observation. It should be noted, however, that these studies only show connections. However, they do not prove that highly processed foods are actually the cause of the health problems observed.
Sources: German Society for Nutrition, Federal Center for Nutrition, BMJ Study, BMJ Study 2, The New York Times, CNN