Nutrition, Diet, and Anti-aging: Low-Salt Diet and Anti-aging

It has long been known that an increase in salt intake raises blood pressure and increases the risk of cerebrovascular and cardiovascular diseases. According to the 2019 National Health and Nutrition Survey, the average salt intake was 10.9 g for men and 9.3 g for women, which is far from the revised “Dietary Intake Standards for Japanese” in 2020, which recommends less than 7.5 g for men and less than 6.5 g for women. An analysis of the NIPPON DATA, which tracked 8072 Japanese participants in the National Nutrition Survey for 24 years, showed that for every 2 g/1000 kcal increase in household salt intake density, total mortality increased by 1.07 times, cardiovascular mortality by 1.11 times, coronary artery disease mortality by 1.25 times, and stroke mortality by 1.12 times, all significantly increased (Fig. 95.1). According to the data from the JPCH study, a multi-purpose cohort study of Japanese people, which followed about 40,000 people for 10 years, the risk of developing stomach cancer was 2.23 times higher in men and 1.32 times higher in women when comparing the lowest and highest quintiles of salt intake. It is often found in people who eat salty foods, such as salted fish and sea urchin paste. There are also reports that the risk is even higher in those infected with Helicobacter pylori. The Japanese Society of Hypertension’s Hypertension Treatment Guidelines 2019 (JSH2019) recommends an intake of less than 6 g/day for hypertensive patients. Sodium is the most important extracellular cation in the body, necessary for many physiological processes, and is strictly regulated in many processes (kidney, biochemistry, endocrinology, immunity, nerves) to maintain serum sodium within the normal range. Therefore, it is not recommended to drastically reduce sodium intake in the short term, and in the elderly and those with reduced kidney function, it is necessary to carefully monitor electrolytes and kidney function while reducing salt intake.