An international study of nearly 30,000 people has linked frequent consumption of ultra-processed foods to differences in brain structure. These changes may contribute to overeating and food addiction, though causation remains unproven. Researchers emphasize the need for further evidence on how food additives affect the brain.
An international team of scientists analyzed brain scans from around 30,000 participants in the UK Biobank, a health database of middle-aged people across the United Kingdom. The study, published in npj Metabolic Health and Disease in 2025, found measurable differences in brain structure associated with higher intake of ultra-processed foods (UPFs). These foods, which contain industrial additives and chemically altered ingredients, showed connections to alterations in feeding-related brain regions, independent of factors like obesity or inflammation.
"Our findings suggest that higher consumption of ultra-processed foods is associated with differences in the brain. These associations could be linked to behavioral patterns such as overeating, though causal relationships cannot be confirmed by our study," said Arsène Kanyamibwa, shared first author from the University of Helsinki. The research, a collaboration between the University of Helsinki and McGill University's Montréal Neurological Institute, highlights potential roles for UPF ingredients like emulsifiers, but calls for more longitudinal studies to confirm this.
Not all processed foods pose risks; plant-based options such as frozen vegetables are beneficial, and processes like milk pasteurization aid health. In contrast, items like processed meats with chemical additives are concerning. "In particular, processed foods of plant origin, such as frozen vegetables, can be recommended. Another good example of the benefits of processing is the pasteurization of milk. In contrast, foods high in chemically modified ingredients and additives, such as processed meat products, are problematic."
Kanyamibwa noted broader implications: "Given the growing body of evidence, reducing ultra-processed food intake and strengthening regulatory standards in food manufacturing may be crucial steps toward ensuring better public health outcomes." The study underscores how modern diets might influence brain function, urging caution in interpreting the associations as direct causes.