Several epidemiological studies have linked Mediterranean-type diets to a low incidence of cardiovascular disease yet few dietary intervention studies have been undertaken, especially in primary prevention, said the researchers from Marseille.

They designed a Mediterranean diet and a low-fat diet and asked 212 men and women with moderate risk factors for cardiovascular disease to follow one of the two diets for three months.

Changes in dietary habits were observed in both groups. Protein, carbohydrate, and fibre intakes increased and fat quality (decreased saturated fat and increased monounsaturated or polyunsaturated fat) improved.

Both diets also had a positive effect on BMI, cholesterol, triacylglycerols and glycaemia. The reductions in total cholesterol, triacylglycerols, and insulinemia remained significant after adjustment for BMI.

"After a three-month intervention, both diets significantly reduced cardiovascular disease risk factors to an overall comparable extent," write the researchers in this month's issue of the American Journal of Clinical Nutrition (vol 82, no 5, pp964-971).