OBJECTIVES: To discuss present knowledge about Mediterranean diet and cardiovascular diseases. DESIGN: Review of existing literature. SETTING AND RESULTS: Epidemiological studies as well as randomised dietary trials suggest that Mediterranean diet may be important in relation to the pathogenesis (and prevention) of CHD. For instance, a striking protective effect of an ALA-rich Mediterranean diet was reported in the Lyon Diet Heart Study with a 50 to 70% reduction of the risk of recurrence after 4 years of follow-up in CHD patients. According to our current knowledge, dietary ALA should represent about 0.6 to 1% of total daily energy or about 2 g per day in patients following a Mediterranean diet, whereas the average intake in linoleic acid should not exceed 7 g per day. Supplementation with very-long-chain omega-3 fatty acids (about 1 g per day) in patients following a Mediterranean type of diet was shown to decrease the risk of cardiac death by 30% and of sudden cardiac death by 45% in the GISSI trial. CONCLUSIONS: In the context of a diet rich in oleic acid, poor in saturated fats and low in omega-6 fatty acids (a dietary pattern characterising the traditional Mediterranean diet), even small doses of omega-3 fatty acids (about 1 g EPA+DHA the form of fish oil capsules or 2 g alpha-linolenic acid in canola oil and margarine) might be very protective. These data underline the importance of the accompanying diet in any dietary strategy using fatty acid complements.