The current study aimed to identify potential psychosocial risk and protective factors contributing to eating disorders in adolescents, and observe any differences between genders and Body Mass Index (BMI) categories. A cross-sectional survey was carried out with a total of 2605 (1063 male) adolescents, who were assessed for disordered eating, body-image satisfaction and investment, appearance/weight-related anxiety, situational dysphoria, media influences, self-esteem, and body appreciation. The results revealed that weight/appearance-related anxiety and situational dysphoria were the most significant risk factors for both genders. Pressures from the media posed a significant risk only for males and the internalization of the thin ideal only for females; however, the internalization of the athletic ideal did not pose as a significant risk factor. Compared to gender, these risk factors did not differ based on BMI. Additionally, body appreciation was found to be a robust protective factor (unlike global self-esteem) for both genders, and across all BMI groups. The findings indicate that the most significant risk and protective factors of eating disorders do not differ largely for male and female adolescents or different BMIs. Intervention and prevention programs would therefore benefit from the inclusion of exercises that reduce the constructs of weight/appearance-related anxiety and situational dysphoria, and promote body appreciation.