There are seemingly opposing findings on social media’s effect on mental well-being. Some studies report no detrimental effects, others no association and others even positive or buffering effects. However, social media has rapidly evolved in a short span of time and so has people’s use of the platforms. Collecting an accurate measure of social media use and other methodological challenges particularly affect data in this area. In this commentary, we discuss two longitudinal studies to elaborate these contracting findings on social media and mental health.