The number of overweight, obese, and adipose children across the world is increasing. Several studies have suggested the correlation between obesity and deficits in executive function. But little is known about the associations between obesity and brain development. This study aims to evaluate whether body mass index (BMI) is associated with the thickness of the cerebral cortex.

This cross-sectional study included a total of 3,190 children (mean age 10 years) with higher BMI. The researchers derived cortical thickness maps from T1-weighted structural magnetic resonance images of the participants. The primary outcome of the study was the mean cortical thickness assessed using a 10-fold nested cross-validation general linear model.

Of 3,190 children included in the study, those with higher BMI had lower cortical thickness. The findings suggested 18 cortical regions that exhibited an inverse association with BMI, with the most significant correlation being observed in the prefrontal cortex. Inverse associations were also found between BMI and dimensional card sorting and matrix reasoning. Mean prefrontal cortex thickness showed mediation in the association between BMI and list sorting.

The research concluded that BMI was associated with a lower cortical thickness, with the most significant impact being observed in the prefrontal cortex.