Muhamad Yehia.. Cairo
Ultra-processed foods (UPFs) are linked to a host of health problems. It may now be easy to detect how much of these foods a person eats from their blood and urine.
Molecules in blood and urine may reveal how much energy a person consumes from ultra-processed foods, a key step to understanding their health impact, a new study has found.
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 researcher at the National Cancer Institute in the United States who led the study published Tuesday in the journal PLOS Medicine.
“It can potentially give us some clues as to what the underlying biology might be between an ultra-processed food association and a health outcome,” Loftfield said
Ultra-processed foods – sugary cereals, sodas, crisps, frozen pizzas, and more – are created through industrial processes with ingredients such as additives, colours, and preservatives not found in home kitchen
They’re ubiquitous in high-income countries, but studying their health impacts is hard because it’s difficult to accurately track what people eat.
For the new analysis, Loftfield and her colleagues examined data from an existing study of more than 1,000 older US adults. More than 700 of them had provided blood and urine samples, as well as detailed dietary recall reports, collected over a year.
The scientists found that hundreds of metabolites – products of digestion and other processes – corresponded to the percentage of energy a person consumes from ultra-processed foods
From those, they devised a score of 28 blood markers and up to 33 urine markers that reliably predicted ultra-processed food intake in people who had typical diets
“We found this signature that was sort of predictive of this dietary pattern that’s high in ultra-processed food and not just a specific food item here and there,” she said.
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 ultra-processed foods and type 2 diabetes, the study found.
Unraveling ultra-processed food’s impact on health
It’s still early research, but identifying blood and urine markers to predict ultra-processed foods consumption is “a major scientific advance,” said Dr Dariush Mozaffarian, who directs the Food Is Medicine Institute at Tufts University in the US and 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.
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 ultra-processed foods on cancer risk.
“There’s a lot of interest across the board – scientifically, public interest, political interest – in the question of: Does ultra-processed food impact health and, if so, how?” she said.