Psychosocial adjustment mediates impacts of playmate positive support on body mass index and overweight risk in adolescents.

OBJECTIVES:We examined the mediation effects of psychosocial adjustment on the impact of playmate positive support throughout childhood and early adolescence (from age 54 months to 11 years) on later body mass index (BMI) and overweight risk in middle adolescence (age 15 years). STUDY DESIGN:This was a prospective cohort study. METHODS:Among 844 children and their families, positive support between child-playmate dyads was repeatedly assessed from child's age 54 months to Grade 5. Long-term positive support between child-playmate dyads throughout childhood and early adolescence was prospectively linked to child's BMI and overweight/obesity status at age 15 years. The average scores of repeated assessments of internalizing and externalizing behavior problems from Grades 3 to 6 were used as mediators. RESULTS:Significant mediations of internalizing and externalizing behavior problems were observed on pathways from positive support between child-playmate dyads to later BMI and overweight/obesity status at age 15 years. The observed mediations were mainly sustained with pronounced magnitudes in girls, but not in boys. CONCLUSIONS:Our findings demonstrated a significant mediating role of psychosocial adjustment. Future research efforts are highly encouraged to replicate our findings and further explore this underlying mediation mechanism.