Gender differences in dietary behaviors among Japanese adolescents

Unhealthy dietary behaviors in adolescence are an important public health problem. Gender differences in dietary behaviors have already appeared during adolescence. However, few studies have assessed a variety of adolescent dietary behaviors in Japan. We aimed to clarify gender differences in unhealthy dietary behaviors among Japanese adolescents. The participants consisted of 84,988 participants from seventh to 12th grades. Unhealthy dietary behaviors were defined according to the National Health and Nutrition Survey. Multivariable logistic regression was used to analyze a nationally representative sample of Japanese adolescents from the 2014 to 2015 Lifestyle Survey. The effective response rate was 51.4%. The prevalence of unhealthy dietary behaviors (skipping breakfast, snacking, eating out, skipping meals, eating alone at dinner, and subjectively poor diet quality) among boys and girls was 14.2% versus 12.4%, 19.6% versus 14.1%, 10.6% versus 7.0%, 7.9% versus 5.6%, 13.3% versus 12.1%, and 12.3% versus 15.8%, respectively. Compared with boys, girls were more negatively associated with skipping breakfast [OR = 0.76 (95% CI 0.73–0.79)], snacking [OR = 0.67 (95% CI 0.65–0.70)], eating out [OR = 0.62 (95% CI 0.59–0.66)], skipping meals [OR = 0.61 (95% CI 0.58–0.65)], and eating alone at dinner [OR = 0.79 (95% CI 0.76–0.83)]. However, girls were more positively associated with subjectively poor diet quality [OR = 1.19 (95% CI 1.14.1.24)]. The findings suggest that gender differences existed in dietary behaviors. Gender differences in dietary behaviors suggest opportunities for tailoring interventions related to dietary education in schools.