Scientists link the share of ultra-processed foods in children's diets to brain response and fat gain

What the results showed

Children who got more of their calories from ultra-processed foods showed a stronger response in a specific brain region to images of appetizing food, and this response was linked to a subsequent increase in body fat percentage. This is reported by Gazeta.Ru citing a study by University of Southern California scientists published in the journal JAMA Network Open.

How the study was conducted

The analysis included 46 children aged seven to ten with normal body weight. The scientists assessed their diet, body mass index, waist circumference, and body composition. During functional MRI, participants were shown images of appealing foods — such as cookies and french fries — alternating with photographs of non-food objects.

Brain response and changes over a year

On average, ultra-processed food accounted for about 68% of the calories in the diet. A higher share of such food was associated with an increased response of the dorsal striatum — part of the corpus striatum involved in motivation, learning, and reward processing. For the ventral striatum, a similar association was not statistically significant.

What this means

A year later, the researchers reassessed the physical indicators: a stronger initial response of the dorsal striatum was associated with a greater increase in BMI and body fat percentage, while the initial share of ultra-processed food was associated with an increase in waist circumference. After the brain response was included in the statistical model, the associations between diet and changes in BMI and body fat percentage weakened. The authors believe that sensitivity to food cues may be one of the links connecting diet with subsequent fat mass gain. It should be noted that the sample was small — 46 children — and this concerns an observational association, not a proven cause-and-effect relationship; the publication did not report other limitations of the study.