The Impact of Different Types of Social Media Use on the Mental Health of UK Adults: Longitudinal Observational Study

Background: Previous studies have explored the association between social media use and mental health among adolescents. However, few studies using nationally representative longitudinal data have explored this relationship for adults and how the effect might change depending on how people use social media. Objective: This study investigated the longitudinal relationship between the frequency of viewing and posting on social media and mental health problems among UK adults. Methods: This study included 15,836 adults (aged 16 years and older) who participated in Understanding Society, a UK longitudinal survey. Social media use was measured with questions about the frequency of viewing social media and posting on social media in Understanding Society Wave 11 (2019-2021). We explored viewing and posting separately, as well as a combined exposure: (1) high viewing, high posting; (2) high viewing, low posting; (3) low viewing, high posting; and (4) low viewing, low posting. Mental health problems were measured in Wave 12 (2020-2022) using the General Health Questionnaire (GHQ-12), a validated scale for identifying symptoms of common mental health problems, where higher scores indicated more mental health problems (0 to 36). Unadjusted and adjusted linear regression models were estimated for viewing social media and posting on social media, adjusting for the baseline GHQ score, gender, age, ethnicity, employment, and education. We found no evidence for effect modification by gender and age so overall associations were reported. Results: In our adjusted models, we found no evidence of an association between the frequency of viewing social media and mental health problems in the following year. We found that adults who posted daily on social media had more mental health problems than those who never posted on social media, corresponding to a 0.35-point increase in GHQ score (β=0.35, 95% CI 0.01-0.68; P=.04). When we considered both social media behaviors, we found that those who frequently viewed and posted on social media scored 0.31 points higher on the GHQ score (β=0.31, 95% CI 0.04-0.58; P=.03) in the following year compared to those who rarely viewed or posted on social media. Conclusions: We found that a high frequency of posting on social media was associated with increased mental health problems a year later. However, we did not find evidence of a similar association based on the frequency of viewing social media content. This provides evidence that some types of active social media use (ie, posting) have a stronger link to mental health outcomes than some types of passive social media use (viewing). These results highlighted that the relationship between social media use and mental health is complex, and more research is needed to understand the mechanisms underlying these patterns to inform targeted interventions and policies.