The study examines the influence of perceived media-transmitted body images in mass media and social media on body dissatisfaction, mediated by the internalization of body ideals through media and self-discrepancy (the difference between the perceived actual self and the perceived ideal self). The body images individuals perceive in their everyday media diet are estimated using a newly developed pictorial scale for women (thinness) and men (muscularity). The perceived body image is formed through mass media (magazines, TV) and social media (Facebook, YouTube, Instagram, Snapchat) formatively. The self-discrepancy theory is used to explain the effect of body images in the media on internalization of these body ideals and body dissatisfaction. Results show that Facebook and YouTube shape body ideals perceive to be prevalent in the media, and these negatively influence internalization and self-discrepancy. Self-discrepancy, in turn, increases body dissatisfaction. However, for males, the perceived body ideals in the media did not influence body dissatisfaction, internalization or self-discrepancy. These results emphasize the importance of combining and comparing mass and social media, and differentiating between females and males concerns regarding body image.