Gender differences in orthorexic eating behaviors: Women were more likely to report pathologically healthful eating than men

Gender differences in orthorexic eating behaviors: A systematic review and meta-analytic integration. Jana Strahler. Nutrition, July 4 2019. https://doi.org/10.1016/j.nut.2019.06.015

Highlights
•    This meta-analysis determines the size of gender differences in pathologically healthful eating.
•    Data from 67 studies including 39’255 participants is summarized.
•    Women were more likely to report pathologically healthful eating than men.
•    Similar effects sizes between general population and high-risk samples were shown.
•    Differences were inconsistently and minimally related to sample's mean age or year of publication.

Abstract
Objective: Besides the ongoing debate about the epidemiological and clinical relevance of pathologically healthful eating, a phenomenon called orthorexia nervosa (ON), there is not much consensus about gender differences in prevalence rates. This study, therefore, provides a systematic review and meta-analytic combination of derived data to better conceptualize the presence and size of gender differences in the prevalence and levels of orthorexic eating behaviors and ON.

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

Results: The results showed significant gender 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 towards 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 gender difference was inconsistently and minimally related to the sample's mean age, year of publication, or gender distribution.

Conclusions: The findings indicate that, depending on the instrument in use, tendencies towards healthy eating are comparable between the genders while 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 pathological healthful eating and ON.

Level of evidence: Level IIa, Systematic review (with homogeneity) of cohort studies.