In January 2019 researchers from the UK published their study to assess whether social media use was associated with depressive symptoms in adolescents, and potential causes of their symptoms. Information from 10,904 14-year-olds was assessed and various pathway models used to examine associations between social media use and depressive symptoms. Results showed that the association between social media use and depressive symptoms was greater for girls than for boys. An analysis revealed that greater social media use was related to online harassment, poor sleep, low self-esteem and poor body image which in turn increased the symptoms of depression. For example, more hours using social media was related to body weight dissatisfaction (over 5 hours usage resulted in a 31% increase in being more likely to be dissatisfied), which in turn was directly linked to symptoms of depression (body dissatisfaction resulted in a 15% increase in symptoms) and indirectly to low self-esteem.
Kelly Y et al. Social Media Use and Adolescent Mental Health: Findings From the UK Millennium Cohort Study. EClinicalMedicine. 2019 Jan 4;6:59-68.