Heavy social media use in early adolescence associated with later depression and anxiety
Findings from a new study could help inform the school curriculum and public health strategies, including digital literacy education and guidance on healthy sleep routines for young people.
Adolescents who spend more than three hours a day on social networking sites at the start of secondary school are more likely to experience symptoms of depression and anxiety two years later, according to new research published in BMC Medicine.
The study, involving researchers from Birkbeck, Imperial College London, Central North West London NHS Foundation Trust, University of Melbourne, University of Basel, and the Swiss Tropical and Public Health Institute, analysed data from more than 2,300 young people in London participating in the Study of Cognition, Adolescents and Mobile Phones (SCAMP), one of the world’s largest adolescent cohort studies of digital technology use.
Researchers found that adolescents aged 11–12 who reported using social networking sites for more than three hours per day had significantly higher levels of depressive and anxiety symptoms by ages 13–15 compared with those who used social media for 30 minutes or less per day.
The study also identified sleep as an important factor. Insufficient sleep and taking longer to fall asleep partly mediated the link between heavy social media use and poorer mental health, suggesting that improving sleep habits could help reduce risks.
The findings point to a potential “threshold effect”, with only the highest levels of use associated with increased risk, while lower levels were not linked to worse mental health outcomes.
Michael Thomas, Professor of Cognitive Neuroscience at Birkbeck and an author of the study, commented: “It is important to keep building the evidence base on this important societal issue, identifying both the benefits and risks of social media use in young people. Longitudinal studies are a key tool to help us tease apart the pathways through which these effects operate, such as the disruption of sleep.”
The researchers also found that the association between social media use and depressive symptoms was stronger in girls than boys, highlighting the need for targeted approaches to prevention and support.
The team used a longitudinal design, following students over time and accounting for a range of factors including socioeconomic background, ethnicity and prior emotional difficulties. Following students over time strengthens confidence that heavy use precedes later mental health symptoms.
While the study shows an association rather than proving cause and effect, the researchers say it highlights the importance of identifying young people with very high levels of social media use and supporting them early.