Numerous nutrient profiling models (NPMs) exist worldwide, but Japan lacks an official NPM. Using the Australian and New Zealand Health Star Rating (HSR) as a reference, “Processed Foods in Japan version 1.0” (NPM-PFJ (1.0)) was developed to fit Japanese food culture and policies. In total, 668 processed foods from the Standard Tables of Food Composition in Japan were analyzed, excluding seasonings/spices, fats/oils, alcoholic beverages, and infant food. The NPM-PFJ (1.0) scoring algorithm was adapted from HSR, with revised reference values for energy, saturated fat, total sugars, sodium, protein, and dietary fiber in alignment with Japanese standards. Reference values for fruits, vegetables, nuts, and legumes (fvnl) remained unchanged. Median scores were 4.5 for HSR and 5.0 for NPM-PFJ (1.0), showing high correlation (r = 0.939, p < 0.01). Thereafter, food categories familiar and meaningful in Japan were defined based on a hierarchical cluster analysis of scoring patterns, creating six categories with distinct characteristics. Finally, the rating algorithm for NPM-PFJ (1.0) was created using each group’s score distribution (10th percentile). The NPM-PFJ (1.0) was developed through a fully transparent and evidence-based process and is expected to facilitate the reformulation of food products by food industries and help consumers easily access healthier processed foods. This model marks a significant step forward in developing an NPM tailored to Japanese food culture and health policies, with the potential to enhance public health.

To address the rising incidence of non-communicable diseases (NCDs) and promote healthier eating habits, Japan requires a culturally tailored Nutrient Profile Model. This study aimed to develop a Nutrient Profile Model for Dishes in Japan version 1.0 (NPM-DJ (1.0)) that corresponds to the nutritional issues and food culture in Japan. The aim of the NPM-DJ (1.0) was to promote the health of the general population, and to prevent the increase in NCDs in Japan. The NPM-DJ (1.0) categorizes dishes into staples, sides, mains, mixed dishes, and mixed dishes with staples. The model evaluates dishes based on energy, saturated fats, sugars, and sodium as restricted nutrients, while considering protein, dietary fiber, and the weight of certain food groups as recommended nutrients. The distribution of the overall score for each dish category was analyzed and a rating algorithm was created. The baseline, modification points, and final scores were significantly lower for side dishes than for staple dishes. In contrast, the baseline points and final scores were significantly higher for mixed dishes with staple. The model effectively differentiated nutritional profiles across five dishes categories, which may promote healthier dish reformulation by food businesses operators and encourage consumers to select healthier dishes.

Dish-based nutrient profile analyses are essential for setting goals to achieve a balanced diet. In 2014, the Japanese government proposed the “Healthy Meal” criteria, which requires a salt content of 3 g/650 kcal per meal. To examine the current intake status of a nationally representative sample, we conducted a series of secondary analyses of the 2014–2018 National Health and Nutrition Survey data. Participants (aged 18–74 years) were grouped as “high-salt” consumers if their salt intake was 3 g/650 kcal or higher and “adequate” consumers if they consumed less than 3 g/650 kcal. A total of 13,615 participants were identified as “adequate” consumers and 22,300 as “high-salt” consumers. The median salt intake in the “high-salt” group was 11.3 g/day, while that in the “adequate” group was 7.5 g/day. Almost all dishes consumed by the “adequate” group had significantly high energy and fat content but low salt content, compared with those consumed by the “high-salt” group. For example, the median energy, fat, and salt contents in the main dishes consumed by the “adequate” group were 173 kcal, 10.4 g, and 0.9 g/dish, respectively, while those in the main dishes consumed by the “high-salt” group were 159 kcal, 8.9 g, and 1.1 g/dish, respectively. Examples of balanced dishes that are low in both salt and fat content can be proposed to help improve the Japanese consumers’ dietary behavior.

Numerous Foods with Function Claims that contain the extract of Pueraria flower (kudzu) isoflavones (PFI) are available in the Japanese market. These are labelled with function claims of reducing visceral fat. However, these foods have not undergone proper safety assessment such as the evaluation of their oestrogenic activity and effects on drug-metabolising enzymes (cytochrome P-450: CYP) in the liver. This study evaluated the estrogenic effect and the hepatic CYP activity and mRNA expression in normal female mice as a safety assessment of PFI (Experiment 1). In addition, the bone mineral density and visceral fat weight in ovariectomised mice (OVX) compared to soy isoflavones (SI) was evaluated to assess the efficacy of PFI (Experiment 2). OVX control fed a control diet, OVX fed a PFI diet (the recommended human intake of PFI), OVX fed a PFI20 diet (20- times the recommended PFI), OVX fed an SI diet (the recommended human intake of SI), and OVX fed an SI20 diet (20 -times the recommended intake of SI) for 28 days in Experiment 2. Body, liver, and visceral fat weights were not affected by the PFI, PFI20, SI, or SI20 diets. The hepatic CYP1A and CYP3A activities were elevated by the SI20 treatment. Ovariectomy-induced bone loss was inhibited by the SI20 treatment, but not by the PFI20 treatment. These results suggest that (1) PFI intake in human doses had no oestrogenic properties and did not affect CYP activity in the liver; (2) there was no evidence that PFI affects the amount of visceral fat in OVX mice.