We investigated the association of dietary fatty acids and plasma antioxidative vitamins with blood pressure in 722 eastern Finnish men aged 54 years, examined in the Kuopio Ischaemic Heart Disease Risk Factor Study in 1984-1986, who had no known hypertension nor any cerebrovascular disease. Allowing for the major anthropometric, dietary, medical and psychological determinants of blood pressure in a multivariate regression analysis, plasma ascorbic acid concentration had a moderate, independent inverse association (P less than 0.0001) and the estimated dietary intake of linolenic acid an inverse (P = 0.026) independent association with mean resting blood pressure. The marked elevation of blood pressure at the lowest levels of plasma vitamin C concentration supports the hypothesis of the role of antioxidants in the aetiology of hypertension.