Your Health Buddies Matter: Preferential Selection and Social Influence on Weight Management in an Online Health Social Network

ABSTRACT

A growing number of online social networks are designed with the intention to promote health by providing virtual space wherein individuals can seek and share information and support with similar others. Research has shown that real-world social networks have a significant influence on one’s health behavior and outcomes. However, there is a dearth of studies on how individuals form social networks in virtual space and whether such online social networks exert any impact on individuals’ health outcomes. Built on the Multi-Theoretical Multilevel (MTML) framework and drawing from literature on social influence, this study examined the mechanisms underlying the formation of an online health social network and empirically tested social influence on individual health outcomes through the network. Situated in a weight management social networking site, the study tracked a health buddy network of 709 users and their weight management activities and outcomes for 4 months. Actor-based modeling was used to test the joint dynamics of preferential selection and social influence among health buddies. The results showed that baseline, inbreeding, and health status homophily significantly predicted preferential selection of health buddies in the weight management social networking site, whereas self-interest in seeking experiential health information did not. The study also found peer influence of online health buddy networks on individual weight outcomes, such that an individual’s odds of losing weight increased if, on average, the individual’s health buddies were losing weight.

Acknowledgments

The author thanks Dr. Margaret McLaughlin, Dr. Janet Fulk, Dr. Peter Monge, and Dr. Jordan-Marsh for their comments on the draft, and reviewers for their comments on the article.

Funding

The author thanks the Annenberg School for Communication and Journalism, University of Southern California, for providing financial support to data collection for the present study.

Additional information

Funding

The author thanks the Annenberg School for Communication and Journalism, University of Southern California, for providing financial support to data collection for the present study. The author also thanks Dr. Margaret McLaughlin, Dr. Janet Fulk, Dr. Peter Monge, and Dr. Jordan-Marsh for their comments on the draft, and reviewers for their comments on the article.