Why do men stigmatize individuals with eating disorders more than women? Experimental evidence that sex differences in conformity to gender norms, not biological sex, drive eating disorders' stigmatization.

Previous research has shown that men are more stigmatizing than women toward individuals with eating disorders, including anorexia nervosa and muscle dysmorphia. We hypothesized that previously observed sex differences in eating disorders' stigmatization are driven by sex differences in individuals' levels of conformity to masculine and feminine gender norms. Young adults ( N = 545) completed validated measures of conformity to masculine and feminine norms and were then randomly assigned to read a character description of a male or female individual with anorexia or muscle dysmorphia. Subsequently, participants' stigmatizing attitudes toward the characters were assessed. Multivariate analyses indicated that participants' conformity to masculine and feminine norms were superior predictors of stigmatization relative to biological sex (male/female). Further, participants' conformity to masculine norms, but not feminine norms, was significantly predictive of stigmatization. Specific masculine norms predictive of eating disorders' stigmatization included self-reliance and heterosexual self-presentation. Our findings argue against the notion that men are intrinsically more stigmatizing of eating disorders than women; rather, sex differences in socialization to masculine gender norms may drive stigmatization. Importantly, our study highlights masculine gender norm conformity as a target for researchers involved in the development of prevention programs for eating disorders' stigmatization.