(1) Summary: Many studies have evaluated the association between traditional media exposure and the presence of body dissatisfaction and body image disorders. The last decade has borne witness to the rise of social media, predominantly used by teenagers and young adults. This study’s main objective was to investigate the association between how often one compares their physical appearance to that of the people they follow on social media, and one’s body dissatisfaction and drive for thinness. (2) Method: A sample composed of 1331 subjects aged 15 to 35 (mean age = 24.2), including 1138 subjects recruited from the general population and 193 patients suffering from eating disorders, completed an online questionnaire assessing social media use (followed accounts, selfies posted, image comparison frequency). This questionnaire incorporated two items originating from the Eating Disorder Inventory Scale (Body Dissatisfaction: EDI-BD and Drive for Thinness: EDI-DT). (3) Results: We found an association between the frequency of comparing one’s own physical appearance to that of people followed on social media and body dissatisfaction and drive for thinness. Interestingly, the level of education was a confounding factor in this relationship, while BMI was not. (4) Discussion: The widespread use of social media in teenagers and young adults could increase body dissatisfaction as well as their drive for thinness, therefore rendering them more vulnerable to eating disorders. We should consequently take this social evolution into account, including it in general population prevention programs and in patients’ specific treatment plans.

Background Anorexia Nervosa (AN) is a key target for E-Health programs considering the many barriers hindering patients’ access to care and the disorder’s severity. Although these programs have become more common and effective, they often have low adherence, especially among youth. This can hinder their implementation and effectiveness in real-world settings. User experience partly overlaps with the acceptability field and may provide insight into factors affecting adherence and adoption of E-Health programs. This study aimed to explore early acceptability and user experience of a companion app prototype for adolescents with AN using user-centered design methods. Methods We developed a prototype containing self-help material and emotions and behaviors evaluation and management features. Then we conducted a mixed evaluation combining semi structured focus group interviews and questionnaires in a clinician group and an AN patient group. We analyzed data using thematic analysis and descriptive statistics. Results The app’s overall appeal was adequate. The user experience questionnaire revealed the weakest dimensions, including novelty, dependability, and efficiency versus stimulation (i.e., ability to induce motivation to use the product) and perspicuity (i.e., easy to understand, to get familiar with). The qualitative data analysis revealed three central axes: acceptability, features, and use. We identified acceptability barriers and facilitators such as the importance of design and customization, especially for adolescents. Psychoeducation was a major feature for participants, as patients highlighted the difficulties they encountered when seeking disorders-related information. Conclusions This study shows the importance of including users in the different stages of an e-health intervention development, in order to identify their needs, general use and compliance patterns, to improve adherence and adoption of the program and its effectiveness.