Trends of Dietary Intakes and Metabolic Diseases in Japanese Adults: Assessment of National Health Promotion Policy and National Health and Nutrition Survey 1995-2019

Health Japan 21 is Japan's premier health promotion policy encompassing preventive community health measures for lifestyle-related diseases. In this repeated cross-sectional survey, we report 24-year trends of type 2 diabetes mellitus (T2DM), obesity, hypertension, and their association with dietary intakes to evaluate Health Japan 21's impact and identify gaps for future policy implementation. We analyzed data from 217,519 and 232,821 adults participating in the physical examination and dietary intake assessment, respectively, of the National Health and Nutrition Survey 1995-2019. Average HbA1c and BMI have significantly increased along with the prevalence of T2DM and overweight/obesity among males. Despite a significant decrease in daily salt intake, the decline in the combined prevalence of Grades 1-3 hypertension was non-significant. Seafood and meat intakes showed strong opposing trends during the study period, indicating a dietary shift in the Japanese population. Neither salt nor vegetable/fruit intake reached the target set by Health Japan 21. Metabolic disease trend differences between males and females highlight the need for a gender-specific health promotion policy. Future Health Japan 21 implementation must also consider locally emerging dietary trends.

Automated summary

Health Japan 21 has had an impact on the trends of type 2 diabetes, obesity, and hypertension in Japan, but there are still gaps in its implementation. The average HbA1c and BMI have increased, along with a higher prevalence of diabetes and overweight/obesity among males. Despite a decrease in daily salt intake, the decline in hypertension prevalence was not significant. The dietary shift in the Japanese population, with opposing trends in seafood and meat intake, highlights the need for gender-specific health promotion policies, and consideration of locally emerging dietary trends.