Abstract
OBJECTIVE: Anorexia nervosa, a restrictive eating disorder that is most commonly seen in females, is associated with alterations in gray matter (GM) and white matter (WM) structures. However, little is known about how restrained eating (RE) and the body mass index-standard deviation score (BMI-SDS) are related to brain morphology and whether sex differences exist in the general pediatric population. METHOD: Participants were 9-year-old girls and boys (n = 2729) from the population-based Generation R Study. BMI-SDS was calculated by adjusting BMI for sex and age, using Dutch growth curves. RE is measured with the Dutch Eating Behavior Questionnaire. All children underwent structural magnetic resonance imaging, and brain volumes were calculated using FreeSurfer. RESULTS: BMI-SDS in girls was positively associated with total intracranial volume and several regional brain volumes. In addition, BMI-SDS showed an inverted U-shaped association with total GM and WM. In girls, RE had a positive linear association with total intracranial, WM, and several regional brain volumes, corrected for BMI-SDS. Additionally, there was an inverted U-shaped association with the amygdala and insula volume. In boys, we found merely positive linear associations between BMI-SDS and brain volumes, and no associations between RE and brain volumes. DISCUSSION: Associations between BMI and brain volumes exist in typically developing children, but there are significant sex differences in the magnitude and shape of the associations. RE is associated with some differences in brain volumes in girls only. Longitudinal studies are needed to assess these associations over a longer period of time.