Social media and applications to health behavior

•Social media presents an unprecedented opportunity to change health through online influence.•Of all the platforms available, Facebook features most commonly in health behavior change research.•Twitter, online communities and apps are increasingly appearing in health research.•Randomized controlled trials investigating the efficacy of social media for health are rare.•Continued research is required to refine the application of social media for better health.

Social media is ingrained in daily life, with high usage and apparent ease of engagement making it an attractive tool for health behavior interventions. Approaches have varied widely in terms of target behavior, social networking platforms used, and intervention characteristics. Targeted applications of Facebook, Twitter, online social communities and apps with social features appear to enhance some aspects of health, and offer unique insights into health-related behavior. However, delivery of an intervention that incorporates an established and popular social media platform does not guarantee impact. Online social media is complex, evolving and nuanced. Future challenges for the field will include evaluating interventions in a diverse populace, and designing features that sustain engagement and behavior change.