Reddit Weight Loss Communities: Do They Have What It Takes for Effective Health Interventions?

Online social networks are an important tool for people to share information and have been extensively used for people to achieve beneficial changes in health. Obesity is a major public health concern that affects about one third of the world's population. In order to alleviate this problem, health professionals are focusing on health interventions, which can be performed online. In this study we analyze three distinct online communities about weight and diet in Reddit. We model our data as 3 directed and weighted graphs of the posts and comments and evaluate the interaction between users of each community. We also analyze specific characteristics of each community, the habits of daily activity of the users and the formation of implicit bonds of friendship through the formation of communities. Our main results show that Reddit is a content-centered social network, in which what matters is what is posted and not who posts. In addition, users tend to create implicit friendship relationships through denser regions of interactions. Our results show that, contrary to expectations, the three communities present the same behavior pattern in a general point of view, which facilitates the development of non-directed online weight loss intervention strategies.