Association between the Portion Sizes of Traditional Japanese Seasonings-Soy Sauce and Miso-and Blood Pressure: Cross-Sectional Study Using National Health and Nutrition Survey, 2012⁻2016 Data

Healthy Eating in Population Models of Nutrition: Asian Diet Style Summary

The population of Japan and Okinawa is known for the longest life expectancy, which many researchers rightly associate with the nature of nutrition existing in these territories. The Japanese diet and Okinawan diet, along with other traditional diets, are real examples of historically established sustainable patterns of healthy eating. Asian eating styles have marked differences from European eating patterns, not only in differences in food sources, but also in eating habits. The article presents the historical, climatic and cultural features of these diets; the issues of food composition, energy and nutritional value of these models of nutrition are considered in detail with an analysis of the differences existing between them; highlights the benefits of products grown mainly in Japan, which are ration-forming for the population of this country; as well as the results of scientific studies on the protective effect of the Japanese and Okinawan diets on human health and disease prevention.

Nutrient Profiles of Dishes Consumed by the Adequate and High-Salt Groups in the 2014-2018 National Health and Nutrition Survey, Japan

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.

Japanese Traditional Miso and Koji Making

Miso is a traditional Japanese seasoning paste produced by fermenting soybeans using the power of koji mold. A recent Japanese cohort study has shown that increased consumption of fermented soybean products is associated with a reduced risk of death in both men and women. In this review, we briefly explain what miso means in the Japanese culture and food industry, varieties of miso available today, and steps involved in miso making. Then, we review early and latest scientific researches in koji mold species, their safety, and beneficial enzymes they produce during fermentation and maturation processes, which play a major part in determining the quality and sensory profile of miso.

Fermentation and the microbial community of Japanese koji and miso: A review

Miso is a well-known traditional Japanese fermented food, with a characteristic savory flavor and aroma, known predominately as the seasoning in miso soup. Miso production involves a two-stage fermentation, where first a mold, such as Aspergillus oryzae, is inoculated onto a substrate to make koji. A subsequent fermentation, this time by bacteria and yeast, occurs when the koji is added to a salt and soybean mash, with the miso left to ferment for up to 2 years. The microbial community of miso is considered essential to the development of the unique taste, texture, and nutritional profile of miso. Despite the importance of microorganisms in the production of miso, very little research has been undertaken to characterize and describe the microbial process. In this review, we provide an overview of the two-stage fermentation process, describe what is currently known about the microbial communities involved and consider any potential health benefits associated with the consumption of miso, along with food safety concerns. As the popularity of miso continues to expand globally and is produced under new environmental conditions, understanding the microbiological processes involved will assist to ensure that global production of miso is safe as well as delicious.

Chinese Traditional Fermented Soy Sauce Exerts Protective Effects against High-Fat and High-Salt Diet-Induced Hypertension in Sprague-Dawley Rats by Improving Adipogenesis and Renin-Angiotensin-Aldosterone System Activity

Although high-fat and high-salt diets are considered risk factors for hypertension, the intake of salty soybean-based fermented foods has beneficial effects. This study explored the potential of Chinese traditional fermented soy sauce (CTFSS) in preventing hypertension by analyzing its effects on adipogenesis and the renin-angiotensin-aldosterone system (RAAS). Male Sprague-Dawley (SD) rats were divided into four groups (n = 6): normal diet (ND), high-fat diet (HD), high-fat diet with saline (HDS, NaCl-8%), and high-fat diet with Chinese traditional soy sauce (HDCTS, NaCl-8%). Each group is administrated 12 weeks by oral gavage as 10 mL/kg dose, respectively. CTFSS supplementation resulted in significantly lower body weight, epididymal fat weight, and systolic blood pressure. Additionally, it decreased the serum total cholesterol (TC), triglyceride (TG), alanine aminotransferase (ALT), aspartate aminotransferase (AST), renin, angiotensin II (Ang II), angiotensin-converting enzyme (ACE), and aldosterone levels. It also increased the urinary volume and improved sodium and potassium ion balance. The gene levels showed significant enhancements in the mRNA levels of renin-angiotensin-aldosterone system-related and adipogenesis-related genes. In addition, CTFSS may prevent hypertension-associated kidney injury. Therefore, this study demonstrates that CTFSS has no harmful effects on hypertension. In contrast, the beneficial effects of CTFSS intake in ameliorating hypertension were shown.

Dietary sodium:potassium ratio and CVD risk factors among Japanese adults: a retrospective cross-sectional study of pooled data from the National Health and Nutrition Survey, 2003-2017

Few studies have reported associations between the Na:K ratio and risk factors related to CVD among the general population in Asian countries. This study aimed to investigate the dietary Na:K ratio association with CVD risk factors among Japanese adults. This retrospective cross-sectional study included 48 800 Japanese participants (19 386 men and 29 414 women) aged ≥20 years, registered in the 2003-2017 National Health and Nutrition Survey. Multivariate OR and 95 % CI for risk of hypertension, high glycated HbA1c levels, hypercholesterolaemia, low serum levels of HDL-cholesterol and high non-HDL-cholesterol levels according to the Na:K ratio were estimated using logistic regression models. Dietary Na:K ratio decreased for both men and women from 2003 to 2017. Higher Na:K ratio and higher hypertension prevalence were observed (multivariate OR (fifth v. first quintiles) 1·27, 95 % CI 1·15, 1·40; Pfor trend < 0·001 for men and 1·12, 95 % CI 1·01, 1·23; Pfor trend = 0·007 for women). Higher Na:K ratio was associated with higher prevalence of high HbA1c levels in men (multivariate OR 1·56, 95 % CI 1·24, 1·96). Prevalence of low HDL-cholesterol levels was increased with higher Na:K ratio (Pfor trend =0·002 for men and <0·001 for women). No significant associations were found between Na:K ratio and hypercholesterolaemia in men or high non-HDL-cholesterol levels in both men and women. Our findings suggest that dietary Na:K ratio is associated with several CVD risk factors among Japanese adults.