Monounsaturated fatty acids, olive oil and blood pressure: epidemiological, clinical and experimental evidence.

Diet has an important role in the prevention and treatment of hypertension. In early epidemiological studies, conducted mainly in the USA, monounsaturated fatty acids showed a deleterious association with blood pressure or no relationship at all. However, more recent studies, conducted in Mediterranean countries, have shed new light on this issue. In the present review we summarise the main results of epidemiological studies and feeding trials, and explain the possible mechanisms through which monounsaturated fatty acids, and specifically olive oil as the major dietary source of this type of fat in Mediterranean countries, could exert a favourable effect on blood pressure.