As shown by the governmental health statistics, the Japanese average life span is at present the longest in the world. A low neonatal death rate, or striking improvements of the medical system or technique have been thought to contribute to this fact. However, nobody doubts that especialy dietary habits, among life style factors, play an important role in maintaining the average life span in Japan. The Japanese diet has changed dramatically in the last 40 years, and the traditional diet is now not so popular, barely maintained by the older. In 1955, fats accounted for only 8.7% of energy intake, but the proportion of fats occupied in the energy intake had increased to more than 25% by 1990. The fat intake is particularly high in the younger. Such dietary change may increase the serum cholesterol levels of Japanese. According to the governmental survey, the average of serum cholesterol levels of Japanese has increased 15 mg/dl in the past ten years. Nowadays, our serum cholesterol levels are comparable to those of American except for the older. If these trends shown in diet and in the serum cholesterol continue, the incidence of ischemic diseases in Japan may increase further. Similar increases will be observed in the incidences of diabetes mellitus and certain cancers. We should advocate strongly the importance of the nutritional education aiming particularly at the younger generation in Japan.
