Japanese-style diet and life expectancy

Japanese-style diets have been linked to Japan’s long life expectancy. However, the prevalence of non-communicable diseases has increased as Japanese diets have become more influenced by Western food culture. Since it is impossible to administer a lifelong diet to humans, rodent studies have addressed the question of which diet is linked to longevity. National surveys were used to compile menus representative of the Japanese diet at various points over several decades. These studies found that the typical Japanese diet in the late 1990s was healthier than the American diet at that time. Furthermore, mice fed a Japanese diet from 1975 showed the slowest aging and longest life expectancy compared to those fed diets from more recent years. Characteristic components of the 1975 Japanese diet included fish, vegetables, fruits, seaweed, soybean foods, dashi soup stock, and fermented seasonings. Although human studies suggest that the 1975 Japanese diet is healthier than the typical Japanese diet today, more research is needed to confirm these results when considering other lifestyle factors.