https://en.wikipedia.org/wiki/Health_in_Japan
Cultural influences
Traditional Chinese medicine was introduced to Japan with other elements of Chinese culture during the 5th to 9th century. Since around 1900, Chinese-style herbalists have been required to be licensed medical doctors. Training was professionalized and, except for East Asian healers, was based on a biomedical model of the disease. However, the practice of biomedicine was influenced as well by Japanese social organization and cultural expectations concerning education, the organization of the workplace, and social relations of status and dependency, decision-making styles, and ideas about the human body, causes of illness, gender, individualism, and privacy. Anthropologist Emiko Ohnuki-Tierney notes that “daily hygienic behavior and its underlying concepts, which are perceived and expressed in terms of biomedical germ theory, in fact, are directly tied to the basic Japanese symbolic structure.”
The Japanese consume more Omega 3. Biggest co morbidity in the US was vascular disease for Covid deaths.