Dietary risk factors of stroke and hypertension in Japan. III. Comparative study on risk factors between farming and fishing villages in Japan.

Abstract

General medical examinations were performed in 2 rural areas of Shimane Prefecture in Japan, one was a farming village and the other a fishing village where incidences of death due to stroke differed, higher in the former and lower in the latter. Comparisons were made on salt and protein intake by analyzing a fasting single spot urine collected in the morning and by blood tests. Urine samples were analyzed for Na, K, urea N (UN), inorganic sulfate (SO4) and creatinine (Cr) and blood samples for cholesterol (Chl), triglyceride (TG), hematocrit (Ht) and Hb. Blood pressure, Na/Cr, Na/K and Ht were higher in the farming village, and K/Cr, UN/Cr, SO4/Cr, SO4/UN, Chl and TG were higher in the fishing village. These findings indicate the higher salt intake and lower intake of K, animal protein and fat in the farming village. This typical dietary pattern of the Japanese may explain the higher incidence of hypertension and stroke in the farming village.