Researchers from the U.S. National Cancer Institute have developed a method to measure how much ultraprocessed food a person eats by analyzing molecules in blood and urine. The study was published in PLOS Medicine in May 2025. Ultraprocessed foods include sugary cereals, soft drinks, chips, and frozen meals. These items make up nearly 60% of the American diet and are linked to serious health problems, such as obesity and type 2 diabetes. They are made using industrial techniques and include additives not found in home cooking.

The study used data from over 1,000 older adults, with more than 700 providing both food records and biological samples. Scientists identified hundreds of metabolites—substances created when the body digests food—that matched the amount of ultraprocessed food people consumed. Researchers then created a scoring system using 28 blood markers and up to 33 urine markers. The method was tested in a 2019 clinical trial with 20 adults who ate both processed and unprocessed meals. The scores clearly showed changes in food intake. Experts say this system offers a more accurate, scientific way to track eating habits. The researchers plan to use it in future studies to explore links between ultraprocessed food and long-term diseases such as cancer.