The magnitude of association between social media use and depressive symptoms was larger for girls than for boys, according to a new study.

Evidence suggests social media use is associated with mental health in young people but underlying processes are not well understood. The new study assesses whether social media use is associated with adolescents’ depressive symptoms, and investigates multiple potential explanatory pathways via online harassment, sleep, self-esteem and body image.

The method for this new study by EClinicalMedicine used population based data from the UK Millennium Cohort Study on 10,904 14 year olds. Multivariate regression and path models were used to examine associations between social media use and depressive symptoms.

The magnitude of association between social media use and depressive symptoms was larger for girls than for boys. Compared with one to three hours of daily use: three to less than five hours has a 26 percent increase in scores versus 21 percent; more than five hours 50 percent versus 35 percent for girls and boys respectively. Greater social media use related to online harassment, poor sleep, low self-esteem and poor body image; in turn these related to higher depressive symptom scores. Multiple potential intervening pathways were apparent, for example: greater hours social media use related to body weight dissatisfaction, which in turn linked to depressive symptom scores directly and indirectly via self-esteem.

The study says that girls reported more hours of social media use than did boys. Over two fifths of girls used social media for three or more hours per day compared with one fifth of boys, and only 4 percent of girls reported not using social media compared to 10 percent of boys. Compared with boys, girls were more likely to be involved in online harassment as a victim or perpetrator (38.7 percent versus 25.1 percent respectively). Girls were more likely to have low self-esteem (12.8 percent versus 8.9 percent), to have body weight dissatisfaction (78.2 percent versus 68.3 percent) and to be unhappy with their appearance (15.4 percent versus 11.8 percent). Girls were more likely to report fewer hours of sleep compared with boys (less than 7 hours 13.4 percent versus 10.8 percent) and to report experiencing disrupted sleep often (27.6 percent versus 20.2 percent) or most of the time (12.7 percent versus 7.4 percent) but were similar in reporting how long it took them to fall asleep.

The study findings highlight the potential pitfalls of lengthy social media use for young people’s mental health. Findings are highly relevant for the development of guidelines for the safe use of social media and calls on industry to more tightly regulate hours of social media use.