Abstract
Like traditional media, information on the World Wide Web may encourage both healthy and unhealthy behaviors. This study reports on the content analysis of a particular genre of Web site that promotes unhealthy behaviors: pro-eating disorder Web sites. Framed in message design theory, the results of this study indicate that messages on pro-eating disorder Web sites promote response efficacy in continuing disordered behaviors, but messages promoting severity and susceptibility to weight gain and self-efficacy were not common. Given the importance of combining response and self-efficacy messages for maximal effectiveness of messages, the pro-eating disorder sites may have limited effectiveness in effecting behavioral change among site visitors.