RESUMO
Introduction: eating disorders(ED)are chronic mental illnesses, highly prevalent within adolescent population, affecting women more than men. Generally, ED are triggered by an unsatisfactory self body-image, which relates to several socio-cultural factors. Objective: To study the prevalence of the risk of developing ED within Chilean high school students, and to evaluate its relation with sex and the school gender composition (SGC): single-sex or coeducational. Method: A transversal-analytic study was performed using three Santiago public high schools: female-exclusive, male-exclusive and coeducational. The Eating Attitudes Test-40 was applied, considering a 30-point score to define qualitatively the risk condition. Results: The sample included 415 students, 52 percent women, with a mean age of 15,9 years (range 14 to 18). The global prevalence of risk for ED was 14,9 percent. The risk condition was significantly higher in women (25,2 percent) than men (4 percent). No differences were found when comparing the prevalence of risk according to the type of school. Discussion: The higher risk for ED among women respect to men was confirmed, and the SGC has no influence on this risk.