I recently attended a standing-room-only parents’ night at a junior high school featuring a renowned and polished speaker. He deftly captivated the packed auditorium with a fear-based, trouble-in-River-City presentation with which many parents are now familiar: Social media leads to suicide, Snapchat is the devil, take away the phones, and drastically cut screen time. Such meetings can inspire palpable fear and panic in parents. Yet the results of high-profile studies, including a recent meta-analysis and the findings of some of my own research, should give them pause. Contrary to conventional wisdom, a weak to nonexistent link exists between social media and mental health. For example, a major recent study found that screen time only accounted for 0.4% of the variance associated with mental health, comparable to the effect of eating potatoes on depression. These questions...