AbstractWith the increasing prevalence of the pro-anorexic movement online, we present a study in which we analyze disclosures across different online contexts, specifically LiveJournal and Twitter. Pro-anorexia is a movement, ubiquitous in several online contexts, in which individuals support and advise those who wish to maintain anorexia. We sought to better understand how the affordances of computer-mediated communication shape disclosures in different online venues. Therefore, we qualitatively analyzed a total of 2,000 messages from LiveJournal and Twitter. Three major themes emerged from the analysis reflecting characteristics of catharsis and actualization, ranges of extreme sentiment, and maintenance of dialectic tensions. Our findings extend existing theoretical considerations on computer-mediated communication and the self-disclosure of stigmatized health information, especially on the topic of pro-anorexia. It also has practical and design implications to better understand individuals who manage and cope with this mental illness through a computer-mediated context.