The transition to college is an important developmental phase, usually met with increased social desirability, access to alcohol, and new peer groups. Recently, research has utilized social media as a predictor of events during college, but few have assessed how social media can influence alcohol use during the transition to college. Methods: Participants (N = 320) were recruited prior to entering their first year of college. Participants were 18 years old, 60.7% were women, with 46.3% identifying as White, 16.5% Hispanic, 14.9% Asian, 9.5% Black, and 7.6% other. Each participant was assessed three times: prior to matriculation, first semester, and second semester of their freshman year. We assessed the effect of exposure to alcohol content via social media on long-term trajectories of alcohol use. We also assessed self-reported sex as a moderator. Results: Exposure to alcohol content (over and above one's own posting of alcohol content) was associated with greater frequency of drinking during the transition to college. In the multi-group model, exposure to alcohol content was associated with greater drinking prior to matriculation for men. However, for women, exposure to alcohol content was associated with greater alcohol use in the first semester of college. Conclusion: Our results indicate exposure to alcohol-related media content is a strong predictor, over and above one's own positing, of increased drinking, and this effect varies by sex and point in time. Our results lend support for more tailored and time-specific prevention programming for incoming freshmen that should integrate social media normative feedback.

Keywords: Social media; alcohol exposure; alcohol use; college transition; sex differences.