Tegan Taylor: And it is becoming increasingly clear that ultra-processed foods, such as sweets, packaged soups, nuggets, sweetened cereals, are not good for your health. But is it because ultra-processed foods are often high in fat, sugar, and salt? Or is there something in the processing? Another new study points to the latter, showing that a higher intake of ultra-processed foods is associated with an increased risk of dying from any cause. So what could be driving this? And should the level of processing be included as a warning label on food, along with the nutritional information we already receive? I have been speaking with the researcher Marialaura Bonaccio.
Marialaura Bonaccio: We wanted to compare how these two ways of looking at food agree or if they say something different about health outcomes. In the case of our study, it was mortality, all-cause mortality, and cause-specific mortality. And we found interesting things.
Tegan Taylor: Well, let’s talk about it. Let’s start with the top line. What effect did eating ultra-processed foods have on death from any cause?
Marialaura Bonaccio: We just confirmed what others have seen; a diet rich in UPF, which is why ultra-processed foods are associated with a higher risk of dying from any cause, but also from cardiovascular diseases and, specifically, ischemic heart disease and cerebral vascular diseases.
But it was also true when we looked at diet from a traditional approach, that means we use the dietary score which basically assesses the nutritional content of the diet, emphasizing fiber intake, vitamins, all the good things that we know we have. to eat every day. And somehow, it negatively scores foods rich in saturated fats, salts, etc. Diets that are not nutritionally adequate, as reflected by this score, are also associated with the risk of cardiovascular and all-cause mortality.
But what happens is that when we looked at these two dimensions of food together, we basically saw that the risk, the risk associated with the traditional way of looking at food, is explained almost entirely, or at least to a greater extent, by the fact that these nutritionally unhealthy foods are also ultra-processed.
Tegan Taylor: Right, so there are some foods that are naturally high in saturated fat, but what you’re saying is that the foods that seem to confer the highest risk on that yardstick also tended to be ultra-processed.
Marialaura Bonaccio: Exactly. So what counts most, the fact that the nutritional balance is not ideal or optimal, or the fact that these foods are ultra-processed. In our study, a greater proportion of the risk associated with this malnourished diet is explained, that is, it disappears or is greatly reduced if we take into account that these foods are also ultra-processed. While the opposite, the other way around, is not true.
I mean, the risk associated with UPF is still there after adjusting for the fact that these foods are also nutritionally unbalanced. The point is that when you look at a diet, especially in this day and age where all the food we put on the table comes mostly from supermarkets and is highly processed, it’s important to consider when you look at the nutritional content of foods as well to take into account account for the fact that they can be ultra-processed.
So researchers are beginning to wonder, if there is any other explanation, actually there are many, one is that these foods are mostly packaged in plastic-based packages. So plastic contains some chemicals that have the ability to migrate from plastic to food. So if you are exposed to large amounts of these foods every day, you are also indirectly exposed to contamination from these chemicals. And this is a hypothesis, but there are also other hypotheses that perhaps point to the fact that these foods, for example, result from a long process of deconstruction of the food matrix. It’s not a whole food, what you eat, but it’s just the result of various processes that basically destroy the food matrix. And this makes, for example, the absorption of some nutrients more available in the body. If you destroy the fiber and then put it back together, it’s not the same as having fiber in the original version.
There was a third that points out that these foods are also fortified with many, many food additives that you don’t usually have in home kitchens, for example, artificial sweeteners instead of sugar, or you’re tasked with preserving foods so they can have a long lifespan, perhaps all of these pathways interact in some way. So you have like, you know, a cocktail effect. And at this point it is difficult to unravel because you have several hypotheses, but none excludes the others. So maybe that’s all that can contribute to what we see in large population cohorts around the world. Also in a population that has a relatively low consumption of this food, like Italy, you can see these huge differences in mortality, and it’s very, you know, alarming, worrying.
Tegan Taylor: What are the political implications of this research? Because many people rely on ultra-processed foods for their food supply, especially people living on lower incomes,
Marialaura Bonaccio: Yes, because they are cheaper, yes. Well, this document that we are talking about was conceived within the framework of a strong debate at European level now, seeking the adoption of a front labeling system, common to all EU countries. Now in Europe it is an option, but it is not mandatory. But the EU wants to choose a mandatory nutrition labeling system on the front of the pack. The one that has gained the most support in recent years is the Nutri-Score. I don’t know if you are…
Tegan Taylor: We have different versions of it.
Marialaura Bonaccio: Yes, but you know, the concept is very similar, because the one you have in Australia is also based on the fact that only nutritional quality is taken into account. They say that this food is good because it is balanced from a nutritional point of view. But the point is that we are not against this system, but simply say that this information derived from an evaluation of nutritional quality should be complemented. So our proposal at the end of the study is to put, along with the nutritional warning, also the processing warning, you know, sugary diet drinks that are very low in calories, they get an A, a green light, but they’re ultra-processed.
Tegan Taylor: Are you saying that what you need is to take it as a whole, the nutritional information, but on top of that, the level of processing?
Marialaura Bonaccio: Yes, you know, a double dimension of considering food.
Tegan Taylor: Marialaura, thank you for spending time with us.
Marialaura Bonaccio: Thank you.
Tegan Taylor: Dr. Marialaura Bonaccio works in the Department of Epidemiology and Prevention of the Neuromed Institute of Italy.
