Sex differences in orthorexic eating behaviors: A systematic review and meta-analytical integration

Other than the ongoing debate about the epidemiologic and clinical relevance of pathologically healthful eating, a phenomenon called orthorexia nervosa, there is not much consensus about sex differences in prevalence rates. The aim of this study was to provide a systematic review and meta-analytical combination of derived data to better conceptualize the presence and size of sex differences in the prevalence and levels of orthorexic eating behaviors and orthorexia nervosa.

Sixty-seven publications were included in the synthesis providing data from k = 89 subsamples (39 255 participants, 67.7% women) for meta-analytical procedures. Separate analyses were conducted for each measurement tool. The impact of four moderators proposed to explain sex differences was examined: sample composition (general population versus special interest in health population; subgroup analysis), and in a meta-regression sample's mean age, year of publication, and sex distribution.

The results showed significant sex differences in only one of four instruments in use. Studies measuring orthorexic behaviors showed that women were significantly more likely to report pathologically healthful eating than men (small effect size). Studies employing tools to assess tendencies toward healthy eating indicated similar levels in women and men. Subgroup and moderator analyses showed comparable effects sizes in general population and high-risk samples, and that the sex difference was inconsistently and minimally related to the sample's mean age, year of publication, or sex distribution.

The findings indicate that, depending on the instrument in use, tendencies toward healthy eating are comparable between the genders, although pathologically healthful eating is slightly more pronounced in women. Future studies will have to adopt valid criteria for diagnosing Orthorexia nervosa and investigate additional factors contributing to pathologic healthful eating and orthorexia nervosa.