Association Between Recollections of Shokuiku During Elementary School, Current Well-Balanced Diets, and Health Behaviours in Japanese High School Students: A Sex-Stratified Study

Background/Objectives: School-aged children in Japan receive food and nutrition education (shokuiku) to promote well-balanced dietary habits. However, among high school students, the association between current well-balanced diets and shokuiku during elementary school years has not been analysed. Herein, we examined the associations between recollections of shokuiku during childhood, current well-balanced dietary habits, and eating and lifestyle behaviours among Japanese high school students, with a particular focus on sex differences. Methods: Overall, 254 second-year high school students (56.3% female) at a public high school in the Hyogo Prefecture, Japan, were included. A hypothetical model was constructed using factors potentially associated with well-balanced dietary habits (i.e., consumption of balanced meals at least twice daily), including recollections of shokuiku during elementary school (education on nutritional balance based on the ‘three food groups’, major nutrients’ role, and breakfast importance) and current eating and lifestyle behaviours. Simultaneous sex-based multi-population analysis was performed. Results: The model demonstrated good fit (GFI = 0.944, AGFI = 0.903, CFI = 0.982, RMSEA = 0.036, and AIC = 145.174). Among female students, current well-balanced dietary habits showed significant positive associations with shokuiku (standardised estimate, female: 0.22, p = 0.005 vs. male: −0.07, p = 0.46), frequency of rice consumption (0.22, p = 0.016 vs. 0.13, p = 0.15), and eating meals with family (0.22, p = 0.003 vs. 0.36, p < 0.001). Conversely, bedtime (−0.28, p < 0.001 vs. −0.03, p = 0.72) showed a significant negative association. Among male students, only eating meals with family showed a significant positive association with current well-balanced dietary habits. Conclusions: Current well-balanced dietary habits among female high school students may be positively associated with shokuiku. Eating rice and meals with family was conducive to well-balanced dietary habits, unlike late bedtime.