Peer effects on childhood and adolescent obesity in China

•First comprehensive study of peer effects on obesity among children and adolescents aged 3-18 years old in China•Results show that peer effects do exist, not only among adolescents but also among younger children.•Individual bodyweight perceptions are associated with average peer BMI, especially female adolescents.

Using data from the China Health and Nutrition Survey (CHNS), this study analyzes peer effects on obesity in a sample of 3- to 18-year-old children and adolescents in China. Even after a rich set of covariates and unobserved individual heterogeneity are controlled for, it is evident that such peer effects do indeed exist. These effects are stronger in rural areas, among individuals at the upper end of the BMI distribution, and especially among females. All else being equal, female adolescents whose peers have a higher BMI are less likely to consider themselves overweight, suggesting that peer effects may be working through changed societal bodyweight norms.