Introduction to Ultraprocessed Foods
By JONEL ALECCIA, Associated Press
Molecules in blood and urine may reveal how much energy a person consumes from ultraprocessed foods, a key step to understanding the impact of the products that make up nearly 60% of the American diet, a new study finds.
What are Ultraprocessed Foods?
It’s the first time that scientists have identified biological markers that can indicate higher or lower intake of the foods, which are linked to a host of health problems, said Erikka Loftfield, a National Cancer Institute researcher who led the study published Tuesday in the journal PLOS Medicine. Ultraprocessed foods – sugary cereals, sodas, chips, frozen pizzas and more – are products created through industrial processes with ingredients such as additives, colors and preservatives not found in home kitchens.
Challenges in Studying Ultraprocessed Foods
They’re ubiquitous in the U.S. and elsewhere, but studying their health impacts is hard because it’s difficult to accurately track what people eat. Typical nutrition studies rely on recall: asking people what they ate during a certain period. But such reports are notoriously unreliable because people don’t remember everything they ate, or they record it inaccurately.
The Need for Objective Measures
“There’s a need for both a more objective measure and potentially also a more accurate measure,” Loftfield explained. To create the new scores, Loftfield and her colleagues examined data from an existing study of more than 1,000 older U.S. adults who were AARP members. More than 700 of them had provided blood and urine samples, as well as detailed dietary recall reports, collected over a year.
Identifying Biological Markers
The scientists found that hundreds of metabolites – products of digestion and other processes – corresponded to the percentage of energy a person consumes from ultraprocessed foods. From those, they devised a score of 28 blood markers and up to 33 urine markers that reliably predicted ultraprocessed food intake in people consuming typical diets. “We found this signature that was sort of predictive of this dietary pattern that’s high in ultraprocessed food and not just a specific food item here and there,” she said.
Validating the Findings
A few of the markers, notably two amino acids and a carbohydrate, showed up at least 60 times out of 100 testing iterations. One marker showed a potential link between a diet high in ultraprocessed foods and type 2 diabetes, the study found. To confirm the findings, Loftfield measured the scoring tool with participants in a carefully controlled 2019 National Institutes of Health study of ultraprocessed foods.
Implications and Future Research
It’s still early research, but identifying blood and urine markers to predict ultraprocessed foods consumption is “a major scientific advance,” said Dr. Dariush Mozaffarian, director of the Food Is Medicine Institute at Tufts University, who was not involved in the study. “With more research, these metabolic signatures can begin to untangle the biologic pathways and harms of UPF and also differences in health effects of specific UPF food groups, processing methods and additives,” he said.
Conclusion
Loftfield said she hopes to apply the tool to existing studies where blood and urine samples are available to track, for instance, the effect of consuming ultraprocessed foods on cancer risk. At a time when support for government research is being cut, funding remains uncertain. “There’s a lot of interest across the board — scientifically, public interest, political interest — in the question of: Does ultraprocessed food impact health and, if so, how?” she said. “How can we fund the studies that need to be done to answer these questions in a timely way?”
FAQs
Q: What are ultraprocessed foods?
A: Ultraprocessed foods are products created through industrial processes with ingredients such as additives, colors, and preservatives not found in home kitchens.
Q: Why is it hard to study the health impacts of ultraprocessed foods?
A: It’s hard to accurately track what people eat, as typical nutrition studies rely on recall, which can be unreliable.
Q: What did the new study find?
A: The study found that molecules in blood and urine can reveal how much energy a person consumes from ultraprocessed foods, and identified biological markers that can indicate higher or lower intake of these foods.
Q: What are the implications of the study?
A: The study’s findings could lead to a better understanding of the health impacts of ultraprocessed foods and potentially inform public health policies and individual dietary choices.
Originally Published: May 20, 2025 at 11:11 AM PDT
The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group and the Robert Wood Johnson Foundation. The AP is solely responsible for all content.
