Nutrient Inadequacy Rates Among Japanese Adolescents Aged 10-14: Cross-Sectional Pooled Analysis From 2018 to 2023 (NICE EVIDENCE Study 5)

Abstract

This study aimed to describe the demographics, nutrient and food group intakes, and adherence to dietary guidelines among Japanese adolescents aged 10-14 years. This cross-sectional study involved 5225 elementary and junior high school students who were surveyed for the NICE EVIDENCE project from 2018 to 2023 (mean age: 11.9 ± 1.4 years; 50.3% male). Nutritional intake was assessed using the brief-type self-administered diet history questionnaire (BDHQ). Nutrient intake inadequacy was assessed in four groups (males and females in the 10-11- and 12-14-year age groups) based on the Dietary Reference Intakes for Japanese (2025). Demographic data indicated that the prevalence of thinness was higher among females, while the prevalence of overweight and obesity was higher among males. Overall, daily breakfast consumption was high but tended to decrease with age. Nutritional inadequacy rates were generally higher in females, particularly in the 12-14-year age group. Major micronutrient inadequacies included iron, calcium, magnesium, manganese, phosphorus, potassium, vitamin D, and vitamin B6. Among the nutrients with established dietary goals, salt equivalent intake exceeded 90% inadequacy in all groups, followed by intake inadequacies in dietary fiber, fat energy percentage, and potassium. Confectionery consumption was relatively high in this population (> 50 g/day), indicating a potential area for dietary improvement. Promoting regular breakfast and increasing micronutrients and fiber intakes, while reducing sodium, total fat, and saturated fat intakes, could address nutritional inadequacies in this population.

Keywords: adolescents; dietary adherence; nutritional adequacy.