Geographical distribution of cerebrovascular disease mortality and food intakes in Japan

The present study focusses on an analysis of the relationship between cerebrovascular disease mortality and food intake. For this purpose, standardized mortality ratios(SMRs) from cerebrovascular disease were calculated for 3341 basic administrative units (wards, cities, towns and villages) between 1969 and 1978 in Japan. The major nutrient intakes and 30 selected food items were obtained from the 1974-1974 Ministry of Health and Welfare, National Nutrition Surveys in 1040 randomly sampled census tracts in 600 areas (18% of the nation). Our analysis demonstrates that the geographical pattern of cerebrovascular disease SMRs in Japan vary from higher in East Japan to lower in the West, and higher in the less urbanized areas, and lower in the more urban ones. Foods positively associated with cerebrovascular disease were rice and other starchy foods, pork, algae (seaweed), and salty foods such as miso (soybean paste), pickled vegetables, soy sauce and salted fish. All of these foods, with the exception of pork, are part of the traditional Japanese diet. On the contrary, mortality was negatively associated with intakes of wheat, butter and margarine, beef and eggs, items considered to be representative of a European diet. Using a stepwise multiple regression analysis, miso and salted fish were selected as positive, and beef and eggs as negative correlates of cerebrovascular disease mortality. According to these results, it is suggested that these four foods are useful as negative and positive indicators of improvement in dietary intakes as related to the reduction in the occurence of cerebrovascular disease.