The “Dietary Reference Intakes” represent the most basic and comprehensive guidelines related to diet and nutrient intake. These guidelines are used as a reference by practitioners in the dietary field. For humans, such guidelines must meet three fundamental requirements: (1) they must be based on evidence obtained from human populations, (2) they must be fully reliable, and (3) they must be useful in practice. If nutrition is to be considered an applied science with a public role to safeguard the lives and health of a given population, then dietary and nutritional guidelines, such as dietary reference intakes, represent a field in which nutritional science must take responsibility. However, such guidelines are based not on the traditional “science of discovery” or “science for clarification of mechanisms”, but on “science of verification” and “epidemiological research based on observation and intervention in the real world”. If we consider dietary reference intakes to be an example of applied science, they may offer a vision of the future of nutritional science.

The National Health and Nutritional Survey (NHNS) comprises three components: a dietary survey, a physical examination survey, and a lifestyle habits survey. The aim of the NHNS is to clarify the physical conditions, nutrient intake, and lifestyle of the Japanese population, and to obtain basic data for the comprehensive promotion of public health. The role of the NHNS in establishing Dietary Reference Intakes (DRIs) has two aspects: formulation and utilization. In terms of formulation, the values obtained from the NHNS are used as representative values for the Japanese population in setting reference values such as adequate intake (AI) and tentative dietary goal for preventing lifestyle-related diseases (DG). However, due to recent changes in the social environment such as increases in the frequency of eating out and eating prepared meals, issues related to the formulation are emerging, such as the declining rate of cooperation with the NHNS. On the other hand, in terms of utilization, as the dietary survey is conducted using the one-day dietary record method, care is needed when comparing it with the DRIs, which set standards for habitual intake by individuals. In this review, we introduce the role of the NHNS in nutrition policy and issues with public health nutrition including the DRIs.

In recent years, the Dietary Reference Intakes (DRIs) for Japanese have shown a shift in focus in order to not only avoid deficiency-related diseases but also prevent nutrient insufficiencies. In this context, it is necessary to identify biomarkers that can be used to assess these insufficiencies. However, there is only limited consensus on reliable biomarkers, highlighting the need to establish new indicators. Additionally, in the 2025 DRIs, osteoporosis has been added to the list of diseases for which a relationship with energy and nutrients has been established, in addition to the conventional list of lifestyle-related diseases. Although vitamin D is crucial for prevention of osteoporosis, a regular diet alone is not sufficient to provide the required amount; thus, the DG for vitamin D has not been established. Vitamin D levels are influenced by not only dietary intake but also synthesis in the skin. Given that ultraviolet radiation exposure and dietary habits in Japan differ from those in other countries, high-quality research on vitamin D levels and their determinants in the Japanese population is essential. However, there has been insufficient human nutritional research centered on vitamins in Japan, making it an urgent priority to establish strong research infrastructure for advancement of this field.

In the context of maintaining and promoting the health of the population, the current “Dietary Reference Intakes for Japanese” is important for not only avoiding deficiencies and preventing acute-onset excesses, but also disease prevention. For this reason, we comprehensively collected information on the extent to which nutrition-related descriptions such as diet, food, and nutrient intakes are included within the clinical practice guidelines in Japan and the types of descriptions that appear. This revealed that only a few guidelines contain descriptions of quantitative values. In Japan, it is desirable to promote research to clarify the quantitative values that are effective for disease prevention. In addition, since descriptions of common nutrients (such as salt or dietary fiber) were found to be listed for different diseases, it is desirable to establish a system that would enable guideline developers to share information about diet, etc. It is hoped that such research will be further advanced through collaboration among researchers specializing in Dietary Reference Intakes and clinical guidelines, thus improving the level of scientific insight for both.

This review summarizes the energy recommendations adopted in the Dietary Reference Intakes for Japanese 2025 (DRIs 2025). In DRIs 2025, body mass index: BMI (target BMI range) was adopted as the reference for maintaining a balance between appropriate energy intake and expenditure. The target BMI range was defined on the basis of the following factors: all-cause mortality, medical expenses, prevalence of lifestyle-related diseases, and physical disabilities in both the working-age and older populations. The process of formulating estimated energy requirements was described, and future tasks were also discussed.