Low-fat diet versus Mediterranean diet in secondary prevention: What is the best option?

Nowadays, medical treatment for cardiovascular disease (CVD) involves a comprehensive set of procedures and drug therapies. However, lifestyle habits remain important to target in order to optimally manage CVD risk. To further explore this issue, the investigators of the CORDIOPREV study have compared the effects of a low-fat diet versus a Mediterranean diet on the secondary prevention of CVD.

A total of 1002 patients (827 men; 175 women) were randomized to receive either a low-fat diet or a Mediterranean diet and were followed for 7 years. During the follow-up period, 198 events occurred (myocardial infarction, revascularisation, ischemic stroke, peripheral artery disease, cardiovascular death) with 87 of them in the Mediterranean diet group and 111 in the low-fat diet group. Increases in total fat intake (from 37.4% to 40.5% of the total energy intake), monounsaturated fatty acids (from 18.4% to 21.4% of the total energy intake) and polyunsaturated fatty acids (from 6.4% to 7.4% of the total energy intake) were observed in patients of the Mediterranean diet group. These increases were mainly attributable to higher intakes of extra-virgin olive oil, nuts and oily fish. On the other hand, as expected, a decrease in total fat intake was observed in the low-fat diet group (from 36.7% to 32.1%). Using the low-fat diet group as the referent, there was a decrease of 25% to 28% in the recurrence of cardiovascular outcomes among individuals of the Mediterranean diet group depending upon the confounding variables considered.

Results of this lifestyle intervention study provide further evidence that we should pay attention to the quality rather than to the quantity of fat in our diet in order to reduce the risk of a recurrent cardiovascular event. This study should help to refine dietary guidelines for the secondary prevention of CVD.