Background: The video-distortion method on a life-size screen is one of the new methods to systematically study the body experience of eating-disordered patients. Methods: Using this method, we have studied body-size estimation in female patients suffering from eating disorders: anorexia nervosa restricting type (n = 87) and mixed type (n = 34); bulimia nervosa (n = 44), and a normal control group (n = 45). Subjects had to estimate a neutral object (neutral response) and their own body size: what they think they really look like (cognitive response); what they feel they look like (affective response), and what they want to look like (optative response). Results: No significant differences were found for the neutral and the cognitive response. Eating-disordered patients clearly did not overestimate their body size. The different subgroups showed interesting differences in the degree of discrepancy between cognitive and affective responses, and in the thinness of their body ideal. Conclusions: Researchers should focus on these elements of body experience, because they are clinically far more relevant than the simple question of over/underestimation.