The present study extends research on thinspiration images, visual and/or textual images intended to inspire weight loss, from pro-eating disorder websites to popular photo-sharing social media websites. The article reports on a systematic content analysis of thinspiration images (N=300) on Twitter and Pinterest. Images tended to be sexually suggestive and objectifying with a focus on ultra-thin, bony, scantily-clad women. Results indicated that particular social media channels and labels (i.e., tags) were characterized by more segmented, bony content and greater social endorsement compared to others. In light of theories of media influence, results offer insight into the potentially harmful effects of exposure to sexually suggestive and objectifying content in large online communities on body image, quality of life, and mental health.