Social media use-genotype interaction on adolescent mental health: Evidence from a parent-offspring trio design

Adolescent mental health has deteriorated markedly over the past decade, with the steepest declines among girls closely tracking the rise of social media. Whether the consequences of social media exposure vary by adolescents' genetic propensities for poor mental health remains unknown. This study examines whether the association between social media use and three mental health outcomes – depressive symptoms, low self-esteem, and body dissatisfaction – varies by sex and genetic propensity for depression, testing two competing theoretical models: the diathesis-stress model and the social push model. Data come from N=2,248 adolescents who were followed from 9 months to age 14 (50.6% female; European ancestry) drawn from the UK Millennium Cohort Study (data collected 2001–2015). A parent-offspring trio design was used to account for confounding by parental genotypes. Results indicate that social media use is more strongly associated with poorer mental health outcomes among girls than boys. Strikingly, the negative associations of social media are strongest among girls with low genetic propensities for depression. These findings support a social push model, suggesting that social media acts as a pervasive adverse environment that compresses genetic differences and elevates mental health risk broadly among girls.