A team of Spanish researchers has discovered the direct relationship between the consumption of ultra-processed foods with depression and changes in volume in specific areas of the brain. The study, which has been led by CIBER (Centro de Investigación Biomédica en Red) and the Girona Biomedical Research Institute Dr. Josep Trueta (IDIBGI), has discovered that ultra-processed food is related to changes in the volume of gray matter of the tonsil

The work also links this type of food with changes in inflammation levels and obesity. The details of the research, which has been led by two CIBER areas, CIBERSAM (Mental Health) and CIBEROBN (Physiopathology of Obesity and Nutrition), have been published in the Journal of Affective Disorders.

Depressive disorders —one of the most common psychiatric disorders in the world— affect more than 300 million people and it is estimated that they will be the main cause of illness in 2030.

Ultra-processed foods, such as sugary drinks, snacks or fast food, are highly processed foods, very low in nutrients and high in additives, preservatives, fats, sugars and sodium that enhance their flavor and make them highly attractive and addictive.

For the study, the team used data from 152 people from whom they collected information about their diet and depressive symptoms. They also took structural MRI images and measured metabolic parameters and inflammatory biomarkers such as white blood cell count, lipopolysaccharide-binding protein, and C-reactive protein.

The objective was to determine the relationship between the consumption of ultra-processed foods and depressive symptoms, and to provide new data on the association between the consumption of these products and the brain gray matter volumes of 152 adult volunteers. Furthermore, they wanted to explore interaction effects with obesity and to find out if inflammatory biomarkers mediate these prior associations.

The results “confirmed our hypothesis” and revealed that the greater consumption of ultra-processed foods is associated with “a greater presence of depressive symptoms, as well as a lower volume in brain regions involved in processing reward and monitoring conflict, essential aspects in decision making.” decisions, including food ones”, explain the main researchers of the study, Oren Contreras-Rodríguez and José Manuel Fernández-Real.

Likewise, the association between the consumption of these products and depressive symptoms was especially notable in the group with obesity (58.6% of the participants), who started with a greater presence of depressive symptoms compared to the group without obesity.

The research supports previous evidence that links the consumption of ultra-processed foods to the risk of suffering from a depressive disorder, and provides new data that associates it with changes in the structure of specific brain networks. Furthermore, it shows that these associations could be dependent on the presence of obesity and the levels of peripheral inflammation.