**Background:** Eating disorders are heterogeneous, disabling psychiatric illnesses with high mortality—anorexia has the highest mortality of any mental disorder, with only 50% of individuals fully recovering. The 2019 Global Burden of Disease study estimated approximately 13.9 million people suffered from anorexia or bulimia, with an additional 41.9 million overlooked cases of OSFED and binge eating disorder, indicating a total global prevalence of 0.7%. Among young females, eating disorders are a leading cause of disability. Body image has been recognized as the most salient and consistent predictor of eating disorder symptomatology. With social media reaching 49% of the global population in 2020 and 91% of UK and US adolescents using social media (over 50% checking at least once per hour), exploratory evidence suggests social media may be triggering body image concerns and eating disorder pathology.
**Methods:** The authors conducted a scoping review following Arksey and O'Malley's framework and the PRISMA checklist. They systematically searched MEDLINE, PsycINFO, and Web of Science for peer-reviewed English-language studies published between January 2016 and July 2021. Search terms covered four concepts: social media, body image, eating disorders, and young people. Inclusion criteria required participants aged 10–24 (or mean age ≤24), any geographic location, and studies examining social media use and body image/disordered eating outcomes. Exclusion criteria included theses, grey literature, studies focused on mass media or general internet use, and social media intervention studies. Two authors independently screened titles/abstracts and full texts. Data extraction covered study type, country, participant characteristics, social media platform(s), theoretical framework, exposures, outcomes, mediators, and moderators. Quality appraisal used three validated tools: the JBI checklist for cross-sectional studies, an adapted JBI tool for quasi-experimental studies, and the CASP checklist for qualitative studies. The review was informed by Rodgers' 2016 integrated theoretical framework incorporating sociocultural theory, self-objectification and feminist theory, impression management, social identity theory, and gratifications theory.
**Key Results:** From 273 identified articles, 50 studies (45 quantitative, 5 qualitative) from 17 countries were included. 90% of studies were conducted in high-income countries; the largest numbers were from Australia (n=12) and the United States (n=11). 48% of studies included only female participants, 2% only male, and 50% included both genders. Where ethnicity was reported, >75% had majority White participants. Most participants were of healthy BMI (82%). 78% of papers referred to Sociocultural Theory. Instagram was the most studied platform (n=15).
KEY EXPOSURES INCLUDED
time spent on social media (significant in 2 of 7 studies, with 3 additional studies finding mediation through social comparison); frequency of use (supported by 2 studies); appearance-focused platforms (Instagram and Snapchat significantly associated with body image concerns and eating disorder pathology in 3 studies); and investment in appearance-related activities (17 studies, with 14 consistently finding associations with body image dissatisfaction and eating disorder risk). For social media trends, 50% of 8 studies on #fitspiration supported the relationship with body image dissatisfaction, 25% partly supported it, and 25% refuted it. One mixed methods study found 17.7% of fitspiration followers were at risk of an eating disorder. For #thinspiration, one cross-sectional study found 96% of included participants followed the thin-ideal, of whom 86% met criteria for a clinical/subclinical eating disorder, and 71% and 65% reported symptoms of depression and anxiety respectively.
OUTCOMES
20 studies explored eating pathology. Five cross-sectional studies found statistically significant associations between social media use and clinical eating disorders (night eating syndrome, binge eating disorder, bulimia nervosa). One study confirmed orthorexia nervosa prevalence of 49% among fitness Instagram followers. 11 studies found associations with disordered eating behaviors—one found 51.7% of adolescent girls and 45% of boys engaged in meal skipping and excessive exercise. 33 studies demonstrated significant associations with body image dissatisfaction. Nine studies revealed associations with poor mental health.
THREE KEY MEDIATORS WERE IDENTIFIED
thin/fit ideal internalization (significant in 11 of 12 studies, 92%), appearance comparisons (significant in 19 of 21 studies, 90%), and self-objectification (significant in 6 studies). Moderators included gender (14 of 18 studies found significant differences, with girls more affected), BMI (3 of 5 studies found high BMI strengthened the relationship), pre-existing body image concerns (4 studies), and social media literacy (3 studies found low literacy was a risk factor, while high literacy was protective).
**Clinical Implications:** The review suggests social media usage is a plausible risk factor for clinical and subclinical eating disorders across different country income groupings. The authors propose a 'self-perpetuating cycle of risk' where individual risk factors (high BMI, poor body image, existing eating disorders) combined with motivations for social media use encourage certain online behaviors, strengthen mediating pathways, and increase risk of poor outcomes. However, the cycle can be broken by protective factors such as high social media literacy and body appreciation. The authors note that up to 80% of eating disorder sufferers remain outside formal healthcare systems, and that social media may normalize disordered eating behaviors, making it harder for young people to recognize they have a problem. They recommend community-level interventions (social media literacy education), societal-level action (government regulation, collaboration with social media companies), and health systems strengthening (screening, integrating social media into treatment plans). The review highlights that eating disorders remain absent from key global health frameworks including the WHO Global Strategy for Women's, Children's and Adolescent Health and the Mental Health Action Plan 2013–2020.