A case-control study concerning the association between diet and peripheral arterial occlusive disease was conducted in Athens, Greece. The case series consisted of 100 patients with this disease, whereas controls were 100 patients with conditions requiring minor surgical care who were admitted to the same teaching hospital. Diet was ascertained through a semiquantitative food frequency questionnaire. Nutrient intakes for individuals were estimated by multiplying the nutrient content of a selected typical portion size for each specified food item by the frequency that the food was used per month and summing these estimates for all food items. Data were analyzed using multiple logistic regression procedures, controlling for total energy intake by taking nutrient residuals and by using multivariate nutrient density models. Saturated fatty acids (odds ratio (OR) and 95% confidence interval (CI) contrasting the 75th centile (upper) with the 25th centile = 1.96 and 1.14-3.39), proteins (OR = 2.86, 95% CI 1.47-5.55), and dietary cholesterol (OR = 6.07, 95% CI 2.74-13.46) were associated with increased risk of peripheral arterial occlusive disease, whereas polyunsaturated fatty acids (OR = 0.48, 95% CI 0.24-0.93) and crude fiber (OR = 0.33, 95% CI 0.17-0.64) were related to reduced risk. Monounsaturated fatty acids and, by inference, olive oil occupy an intermediate neutral position between polyunsaturates and saturates (corresponding OR = 1.14, 95% CI 0.68-1.91). Higher intakes of fiber and vitamin C were associated with lower risk of peripheral arterial occlusive disease. The low occurrence of atherosclerotic diseases in Greece and other Mediterranean countries may be due to the substitution of olive oil in place of saturated fats and/or the consumption of a diet high in vegetables, fruits, and other fiber-containing foods.