Objective: This study investigated longitudinal relationships between social media usage and binge eating (BE) in early adolescence and explored potential moderating effects of sex and BMI.

Methods: Data from the Adolescent Brain Cognitive Development (ABCD) Study, including 1940 participants aged 11 to 12 years at Wave 1, were analyzed over three annual waves. Social media addiction (SMA) scores and time spent on social media were calculated from self-report questionnaires. BE symptoms were evaluated using the Kiddie Schedule for Affective Disorders and Schizophrenia (KSADS-5) through self-reports and parent reports. Modified Poisson regression was used to estimate associations, adjusting for demographic and behavioral covariates.

Results: SMA symptoms, but not time on social media, were cross-sectionally and prospectively associated with BE. Prospective associations were stronger in male adolescents and differed by baseline body weight. The consistently high SMA group showed the strongest association with follow-up BE compared with the consistently low SMA group, whereas decreased and increased SMA groups showed similarly positive associations.

Conclusions: SMA scores predict BE in early adolescence, with differentiation in the relationship by sex and weight status. Further observational and interventional research could illuminate underlying mechanisms and test the value of targeting social media-addictive behaviors to mitigate the risk of disordered eating.