Social processes underpin everything from our lifestyle choices, our health decisions, to the way healthcare is conceived and delivered. Social media—information tools that both exploit and celebrate our social nature—are beginning to be used across healthcare, and proponents see this technology reshaping everything from disease management to biomedical research. Social media are increasingly finding application in public health, including innovative approaches to detecting and tracking infectious disease outbreaks. However, social media could have an even stronger role, enabling us to treat socially shaped diseases such as obesity, depression, diabetes, and heart disease. In this talk I outline the growth of social network thinking and describe several current uses of social media in healthcare and public health, before describing how our understanding of social networks and media could be harnessed for this stronger role of treating socially shaped diseases.