PURPOSE: Research on adolescent social media use focuses on negative mental health outcomes, with less attention on potential positive outcomes. The current study addresses this limitation by investigating associations between adolescent social media use and both psychological well-being and psychopathology. METHODS: Three US-based pediatric cohort sites participating in the National Institutes of Health Environmental influences on Child Health Outcomes study contributed cross-sectional survey data. Adolescents (13-18 years) self-reported the time spent and type of (active, passive) social media use, and their psychological well-being (Patient-Reported Outcome Measurement Information System [PROMIS] Life Satisfaction and Meaning and Purpose), psychopathology (Strengths and Difficulties Questionnaire and PROMIS Depressive Symptoms), and peer relationship quality (PROMIS Peer Relationships). We estimated associations between social media use and 4 mental health groups aligned to the dual factor model of mental health (high well-being/low psychopathology
high well-being/high psychopathology
low well-being/low psychopathology
low well-being/high psychopathology), and tested interactions with peer relationships. Models were adjusted for age, sex, race, ethnicity, and family income. RESULTS: Participants (N = 963) were sociodemographically diverse (22% income ≤130% federal poverty level
42% adolescents of color). Elastic net regressions revealed more hours using social media increased the probability of being in the high psychopathology/low well-being group
adolescents with poor peer relationships spending ≥7 hours/day on social media had the greatest risk of poor mental health. Positive peer relationships were the strongest predictor of positive mental health. DISCUSSION: Peer relationships were the most meaningful contribution to adolescent mental health, and quality of social media use had little influence.