There has been a notable increase in social media and Internet use over recent decades, not only for social interaction or entertainment, but also for working and meeting tools, as seen during the COVID-19 pandemic. A relationship between this usage and the development of mental illness is frequently hypothesized, but a few studies have empirical findings. This study is a systematic review of the relationship between social media use and depression or anxiety. Our Medline search yielded 1,747 papers. Our study found a strong and often bidirectional relationship between social media use and depression or anxiety. This relationship was frequently related to problematic social media use. No definite linear relationship was found between time spent using social media and depressive or anxious symptoms, but usually, the longer the time spent in that activity, the worse the outcomes. Factors related to problematic social media use were often different for men and women. Other variables may also play a role, such as nighttime-specific use, emotional involvement, and whether the individual behaves as an active or passive user. Evidence from this review provides a solid base for recommending cautious use of social media. Intense use and unhealthy habits, evidenced by addiction symptoms, may be problematic in less resilient individuals.
Keywords: anxiety; depression; problematic social media use; social media; well-being.