This study comprehensively examined the associations between shokuiku (food and nutrition education) during school years, current well-balanced diets, and current eating and lifestyle behaviours of Japanese female university students. A hypothetical model was developed using factors potentially associated with well-balanced diets. A simultaneous multipopulational analysis was performed according to the living arrangements of 148 female Japanese students (48.6% living alone) from a registered dietitian course. The analysis showed acceptable goodness of fit and a significant positive path from shokuiku during school years (living alone: standardised estimate 0.29, p = 0.004; with family: 0.32, p = 0.006) and a negative path from eating out frequency (−0.19, p = 0.039; −0.24, p = 0.017) towards a well-balanced diet. A significant negative path was identified from late bedtimes (−0.45, p < 0.001) and home meal replacement use frequency (−0.24, p = 0.010) in those living alone and from late-night snacking frequency (−0.27, p = 0.007) in those living with family. Well-balanced diets in female university students may be positively associated with shokuiku during school years and limited by a late bedtime, eating out, and home meal replacement use in those living alone, and by late-night snacking and eating out in those living with family.

Background/Objectives: In a demographic increasingly at risk of obesity and hypertension, whether dietary behaviours associated with hypertension prevention, such as restricting salt intake and consuming potassium-rich fruits and vegetables, contribute to obesity prevention is unclear. Therefore, we aimed to investigate the structural associations of dietary salt restriction practices with body mass index (BMI) and the mediating role of the dietary sodium/potassium (Na/K) ratio in middle-aged and older Japanese adults. Methods: This cross-sectional survey included 418 participants aged 40–69 years, residing in Hyogo, Japan. Simultaneous multi-population analysis according to sex was performed using a hypothetical model to explore associations of dietary salt restriction practices with BMI, mediated by the dietary Na/K ratio, as well as the role of BMI-related eating behaviours. Results: Dietary salt restriction was associated with a low dietary Na/K ratio (standardised estimate: –0.21, p = 0.001 for men; –0.19, p = 0.002 for women) in both sexes. Dietary salt restriction was associated with lower values of BMI in men (0.21, p = 0.004), mediated by the Na/K ratio; a direct but relatively weak association with lower values of BMI was observed in women (−0.16, p = 0.018). In men, eating out frequently was associated with higher values of BMI (0.20, p = 0.005). Conclusions: Dietary salt restriction practices in middle-aged and older adults may contribute to obesity prevention, and dietary Na/K ratio may play a mediating role in men but not in women; additionally, eating out was associated with higher values of BMI in men.

Few young Japanese adults regularly consume a well-balanced diet composed of staples, main courses, and sides. We hypothesised that adopting the recommended planetary health diet with regular breakfast consumption would promote well-balanced diets among young Japanese male undergraduates. This study aimed to examine the structural association between the planetary health diet with regular breakfast consumption and a well-balanced diet intake. This cross-sectional study included 142 male engineering undergraduates who completed a 2022 online questionnaire via Google Forms at a public university in Hyogo Prefecture. The planetary health diet comprises the consumption of the recommended eight items. A covariance structure analysis was performed in a hypothetical model with factors (regular breakfast consumption and eight items) potentially associated with the intake of a well-balanced diet at least twice daily. After excluding chicken dishes and nuts from the eight recommended items of the planetary health diet, goodness-of-fit became acceptable. Frequent consumption of the remaining six recommended items (fish, eggs, soybeans/soybean products, dairy foods, vegetables, and fruits) was significantly positively correlated with regular breakfast consumption and a significant positive path to a well-balanced diet. Among male university students, regular breakfast consumption and the planetary health diet may lead to a well-balanced diet.

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.

Few young Japanese adults regularly consume a well-balanced diet composed of staples, course dishes, and sides. We hypothesised that adopting the recommended planetary health diet with regular breakfast consumption would promote well-balanced diets among young Japanese male undergraduates. This study aimed to examine the structural association between a planetary health diet with regular breakfast consumption and well-balanced diet intake. Participants were 142 male undergraduates who completed a 2022 online questionnaire via Google Forms in a cross-sectional study at a public university in Hyogo Prefecture. A planetary health diet comprises the consumption of the recommended eight items. A covariance structure analysis was performed in a hypothetical model with factors (regular breakfast consumption and eight items) potentially associated with the intake of a well-balanced diet at least twice daily. Acceptable goodness-of-fit was obtained by excluding chicken dishes and nuts from the eight recommended items of the planetary health diet. Frequent consumption of the remaining six recommended items (fish, eggs, soybeans/soybean products, dairy foods, vegetables, and fruits) was significantly positively correlated with regular breakfast consumption and a significant positive path to a well-balanced diet. Among male university students, regular breakfast consumption and a planetary health diet may lead to a well-balanced diet.