An energy-dense diet is cross-sectionally associated with an increased risk of overweight in male children, but not in female children, male adolescents, or female adolescents in Japan: the Ryukyus Child Health Study

Epidemiologic evidence concerning the role of dietary energy density in increased body weight status during childhood and adolescence is limited, particularly in non-Western populations. We investigated the hypothesis that higher dietary energy density is associated with increasing risk of overweight in Japanese children and adolescents. This Japanese cross-sectional study included 15 974 children (6-11 years old; 7956 boys and 8018 girls) and 8202 adolescents (12-15 years old; 3944 boys and 4258 girls). Dietary intake was assessed using a self-administered diet history questionnaire for children and adolescents. Dietary energy density was calculated based on foods only (excluding beverages). Body mass index (BMI) was calculated from self-reported body weight and height. Overweight (including obesity) was defined according to the International Obesity Task Force age- and sex-specific BMI cutoffs, which correspond to an adult BMI of at least 25 kg/m2. The overall prevalence of overweight was 13.2%. Mean dietary energy density was 5.02 (standard deviation, 0.59) kJ/g. After adjustment for potential confounding factors, dietary energy density was positively associated with the risk of overweight in male children (P for trend = .048). No such associations were observed among female children, male adolescents, or female adolescents. In conclusion, this large cross-sectional study in Japan suggests that an energy-dense diet is associated with an increased risk of overweight in male children, but not in female children, male adolescents, or female adolescents.