How much ultraprocessed food do you eat? The answer might depend on who's doing the counting.
In a new Swedish study, researchers found that ultraprocessed foods made up about 45% of adults' daily calories. But when they changed how they classified certain foods, that number dropped to just 23%. The finding highlights a growing challenge in nutrition research: Foods grouped under the same ultraprocessed label can be very different from one another.
The study, published in Nutrition Journal, examined dietary information from more than 6,700 Swedish adults, teenagers and young children. Researchers wanted to understand not only how much ultraprocessed food people ate, but also how those foods related to overall diet quality and body weight.
Ultraprocessed foods are generally defined as industrially manufactured products containing ingredients or additives not typically used in home cooking. The category includes familiar items such as soda, candy and packaged snacks. But it also can include whole-grain bread, breakfast cereals and other foods that provide important nutrients.
That creates a problem when researchers try to measure how much ultraprocessed food people consume. Some products are easy to classify. Others depend on the ingredients used or how they were prepared.
To see how much those decisions matter, the Swedish researchers calculated ultraprocessed food consumption using different approaches.
Under their main approach, ultraprocessed foods accounted for approximately 45% of daily calories among adults, 52% among teenagers and 46% among young children. When researchers took a more restrictive approach to foods that were harder to classify, those figures fell to 23%, 26% and 29%, respectively.
Bread was one of the biggest reasons for the difference. Depending on its ingredients, a loaf of bread could be classified as ultraprocessed even if it was a whole-grain product with a favorable nutritional profile.
But while the estimated amount of ultraprocessed food changed considerably, another finding remained fairly consistent: People who ate more foods in this category generally had less nutritious diets.
Across the age groups, higher ultraprocessed food consumption was associated with more added sugar and less fiber and whole grains. People who ate more of these foods also tended to get lower amounts of several important vitamins and minerals.
There were some interesting exceptions, however.
Among young children, those who consumed more ultraprocessed foods tended to get more iron and vitamin E. Researchers suggested that fortified cereals and porridges, which can fall into the ultraprocessed category, may help explain the difference.
That matters because fortified foods can help children get nutrients they need. Avoiding them simply because they're labeled ultraprocessed could mean overlooking a useful source of nutrition.
The findings also challenged some common assumptions about ultraprocessed foods. For example, higher consumption was associated with lower salt intake across all three age groups. Researchers cautioned that this unexpected result may partly reflect how salt was estimated in home-prepared meals.
The relationship with body weight was less convincing. Adults who ate more ultraprocessed food had slightly higher body mass index measurements in some analyses, but the relationship wasn't consistent across all the researchers' calculations. No clear relationship emerged among teenagers or young children.
Because the study looked at people's existing eating habits at a single point in time, it couldn't determine whether ultraprocessed foods caused differences in diet quality or weight.
There are other limitations, too. The research relied on Swedish dietary surveys collected during different periods, with the adult data dating back to 2010–2011. Some groups also had relatively low participation rates, so the findings may not fully reflect current eating habits in Sweden or elsewhere.
Still, the study offers a useful reminder that the term ultraprocessed doesn't tell us everything about what's in our food.
A sugary soft drink and a fortified breakfast cereal may share the same classification, but that doesn't mean they offer the same nutritional value. And while diets high in ultraprocessed foods were generally less nutritious in this study, the findings suggest that looking at individual foods and their nutritional content matters alongside how they're made.
The research received public funding from the Swedish Research Council for Health, Working Life and Welfare and through a Swedish government agreement supporting medical research. One co-author is editor-in-chief of Nutrition Journal but was not involved in reviewing or making editorial decisions about the manuscript.