In this paper, we examine the causal impact of weight on adolescent mental health. Using the China Family Panel Studies, we find significant negative effects of adolescent weight, instrumented by cohort‐level parental body mass index (BMI), on mental illness. In particular, a one standard deviation increase in adolescent BMI z‐score decreases the K6 score by 0.766 (or 0.232 standard deviations). This finding is contrary to recent evidence from adults. We find this contrast can partly be explained by the different impacts of adolescent weight on self‐image and social relationships. Unlike adults, heavy adolescents feel that they are popular among peers in China.

No abstract