Teens often make decisions about high-risk behaviors based on their perceptions of their peers' activities. They tend to over-estimate the degree to which peers partake in these behaviors, and it is easy to see how social media may contribute. Here is some interesting research on the effects of social media on teens' drinking behavior. "Teens exposed to their friends’ alcohol-related social media posts were more likely to start drinking. In fact, exposure to alcohol-related posts by peers was predictive of the adolescent drinking a year later... Furthermore, a teen’s beliefs about peer approval and disapproval of drinking act as another process leading to drinking behaviors."