Recently, the Wall Street Journal ran an article about how Instagram was affecting teen mental health. In particular, some internal studies at Facebook (which owns Instagram) appeared to confirm that when teen girls used the site, they suffered poorer body image and were at increased risk for depression and eating disorders. But is social media use itself at fault for making teen mental health worse? While some studies suggest it is, others paint a more nuanced picture, finding it difficult to pinpoint problems with screen time itself versus other factors sometimes associated with social media use that may reduce teen well-being—such as cyberbullying or social isolation. Plus, current conclusions are often based on data from a single point in time, which makes it hard to prove that extended screen time actually causes poorer mental health. Now, findings from an international study on teens add more to this debate and point toward potential guidelines for screen use. Focusing …