Modelling of salt intake reduction by incorporation of umami substances into Japanese foods: a cross-sectional study

Abstract

Background Evidence has demonstrated that excess sodium intake is associated with development of several non-communicable diseases. The main source of sodium is salt. Therefore, reducing salt intake in foods is an important global public health effort to achieve sodium reduction and improve health. This study aimed to model salt intake reduction with 'umami' substances among Japanese adults. The umami substances considered in this study include glutamate or monosodium glutamates (MSG), calcium diglutamate (CDG), inosinate, and guanylate. Methods A total of 21,805 participants aged 57.8 years on average from the National Health and Nutrition Survey was used in the analysis. First, we employed a multivariable linear regression approach with overall salt intake (g/day) as a dependent variable, adjusting for food items and other covariates to estimate the contribution of salt intake from each food item that was selected through an extensive literature review. Assuming the participants already consume low-sodium products, we considered three scenarios in which salt intake could be reduced with the additional umami substances up to 30%, 60% and 100%. We estimated the total amount of population-level salt reduction for each scenario by age and gender. Under the 100% scenario, the Japan’s achievement rates against the national and global salt intake reduction goals were also calculated. Results Without compromising the taste, the 100% or universal incorporation of umami substances into food items reduced the salt intake of Japanese adults by 12.8–22.3% at the population-level average, which is equivalent to 1.27–2.22 g of salt reduction. The universal incorporation of umami substances into food items changed daily mean salt intake of the total population from 9.95 g to 7.73 g: 10.83 g to 8.40 g for men and 9.21 g to 7.17 g for women, respectively. This study suggested that approximately 60% of Japanese adults could achieve the national dietary goal of 8 g/day, while only 7.6% would meet the global recommendation of 5.0 g/day. Conclusions Our study provides essential information on the potential salt reduction with umami substances. The universal incorporation of umami substances into food items would enable the Japanese to achieve the national dietary goal. However, the reduced salt intake level still falls short of the global dietary recommendation.

Umami Characteristics and Taste Improvement Mechanism of Meat

“…The population-level average of the 100% or universal incorporation of umami compounds into food items decreased the salt intake of Japanese adults by 12.8%–22.3%, or 1.27%–2.22% of reduced salt, without sacrificing flavor. The daily mean salt consumption of the general population decreased from 9.95 g to 7.73 g as a result of the widespread use of umami compounds in food items: for men, this meant 10.83 g to 8.40 g and for women, it meant 9.21 g to 7.17 g. According to this study, only 7.6% of adult Japanese could fulfill the global recommendation of 5.0 g/day, although almost 60% could satisfy the national dietary goal of 8 g/day ( Tanaka et al, 2023 ).…”

“…The daily mean salt consumption of the general population decreased from 9.95 g to 7.73 g as a result of the widespread use of umami compounds in food items: for men, this meant 10.83 g to 8.40 g and for women, it meant 9.21 g to 7.17 g. According to this study, only 7.6% of adult Japanese could fulfill the global recommendation of 5.0 g/day, although almost 60% could satisfy the national dietary goal of 8 g/day. (Tanaka et al, 2023).…”

Salt reduction behavior of adults in Anhui province in 2019: a cross-sectional survey of 3,378 participants

“…Nitrites contained in pickled products can improve the flavor by inhibiting lipid peroxidation and preventing the food from becoming rancid ( 26 ). Reducing salt in food may reduce its taste, making older people hesitant to adopt salt reduction measures ( 27 ). Younger people were also more likely to refuse or consume less because they were more likely than older people to be aware that nitrites in pickled foods might have harmful effects on their health ( 18 ).…”