Long-term consequences of adolescent social media use on mental health in young adulthood

Abstract Background There are growing concerns that social media may negatively impact adolescents’ mental health. However, most studies are cross-sectional, or short-term longitudinal studies, limiting conclusions about long-term effects. This study investigates whether social media use at age 15/16 is associated with symptoms of depression and anxiety five years later. It also explores differences by gender, socioeconomic status (SES), and physical activity. Methods Data come from a nationally representative cohort of Swedish adolescents. In 2017, 5535 students in grade 9 (age 15/16) completed a self-report survey. In 2022, 3193 participated in follow-up. Social media use (hours/day) was self-reported; depression and anxiety were measured using PHQ-4. Moderation by gender, SES, and physical activity were tested. Linear regression models were estimated. Results In unadjusted models, social media use at age 15/16 was positively associated with anxiety and depression five years later, but these associations were no longer significant after adjusting for confounders. No significant moderation by gender, SES or physical activity was observed. Conclusions Among Swedish adolescents, time spent on social media is not associated with more symptoms of anxiety or depression five years later. If the literature reaches consensus that social media use does not have long-term effects on mental health, an important implication is that efforts to reduce social media use by adolescents are unlikely to prevent mental health problems. Key messages • Frequent social media use in adolescence is not linked to symptoms of depression and anxiety in young adulthood. • Future longitudinal studies should examine which types of social media activities or experiences may be associated with negative outcomes.