NIH researchers develop biomarker score for predicting diets high in ultra-processed foods

For the first time, scientists at the National Institutes of Health (NIH) have found a way to measure how much ultra-processed food someone eats by looking at substances in their blood and urine. These substances, called metabolites, are what’s left behind after your body digests and uses food.

Usually, researchers rely on people filling out diet questionnaires to know what they eat, but these can be unreliable. People might forget, guess, or not be aware of how processed their food is. This new method is different—it's a scientific test that looks at the actual physical effects of eating processed food in the body. “Limitations of self-reported diet are well known. Metabolomics provides an exciting opportunity to not only improve our methods for objectively measuring complex exposures like diet and intake of ultra-processed foods, but also to understand the mechanisms by which diet might be impacting health,” said lead investigator Erikka Loftfield, Ph.D., M.P.H., of NIH’s National Cancer Institute.

Diets high in ultra-processed foods, which are defined as ready-to-eat or ready-to-heat, industrially manufactured products, typically high in calories and low in essential nutrients, have been linked to increased risk of obesity and related chronic diseases, including some types of cancer. Large population studies quantifying the health effects of ultraprocessed foods typically rely on self-reported data from dietary questionnaires. Such measures may be subject to differences in reporting and may not account for changes in the food supply over time. As a result of this study, researchers now have an objective measure of ultra-processed food intake to help advance the study of associations between ultra-processed foods and health outcomes.

The researchers studied both large groups and a small clinical trial where volunteers followed very controlled diets—one with mostly ultra-processed food and one with none. By comparing samples from these diets, they identified patterns in the metabolites that matched how much processed food was eaten. Using this information, they created a "poly-metabolite score", which is like a new tool or scale that can objectively tell how much ultra-processed food a person has eaten.

This discovery could improve nutrition research by giving scientists a more accurate way to study the link between diet and diseases like cancer, diabetes, and obesity—without having to rely only on people’s memory or honesty about their eating habits. However, more studies are needed in different types of people to make sure this tool works well for everyone.

SOURCE; National Institutes of Health (NIH)