brand logo

Am Fam Physician. 2006;74(9):1610-1612

Coronary heart disease (CHD) is less common in Mediterranean countries than in other industrialized nations. Previous studies have associated Mediterranean dietary practices with reduced mortality. Two components of the Mediterranean-style diet (olive oil and nuts) contain ingredients that may have beneficial effects on cardiovascular risk. Estruch and colleagues compared the short-term effects of two Mediterranean-style diets and a low-fat diet on cardiovascular risk markers.

The multicenter, randomized trial was a three-month subset of the four-year Prevención con Dieta Mediterránea (PREDIMED) study and involved 772 adults at high cardiovascular risk who had no symptoms or history of CHD. The investigators defined high risk as being a man between 55 and 80 years of age or a woman between 60 and 80 years of age with type 2 diabetes or three or more CHD risk factors (see accompanying table). Potential participants were excluded if they had a severe chronic illness, allergy or intolerance to olive oil or nuts, or were unlikely to change diets.

Eligible participants were randomly assigned to one of three diet groups: (1) low-fat diet; (2) Mediterranean diet with olive oil; (3) Mediterranean diet with nuts. Baseline health and demographic characteristics of all groups were similar. Each participant met with a dietitian who offered advice and meal plans based on the type of diet assigned. In addition, the Mediterranean diet groups met with the dietitian in a group session and received free servings of olive oil or nuts.

Current smoking
Blood pressure higher than 140/90 mm Hg or taking drugs for hypertension
Low-density lipoprotein cholesterol level of 160 mg per dL (4.15 mmol per L) or higher or taking drugs for hyperlipidemia
High-density lipoprotein cholesterol level of 40 mg per dL (1.05 mmol per L) or lower
Body mass index of 25 kg per m2 or higher
Family history of premature coronary heart disease

After three months, the Mediterranean diet groups had statistically significant greater improvements in systolic and diastolic blood pressures, fasting blood glucose and insulin levels, and high-density lipoprotein cholesterol levels compared with the low-fat diet group. The low-fat diet group experienced no change in average systolic blood pressure. Participants with preexisting hypertension who followed either Mediterranean diet demonstrated the largest blood pressure reductions.

The authors conclude that the two Mediterranean-style diets were more effective than a low-fat diet at improving cardiovascular risk markers after three months. They also conclude that the high-fat content of the Mediterranean-style diets did not lead to weight gain. It remains to be seen if the PREDIMED study, when completed, will link these short-term improvements in risk markers to long-term improvements in clinical outcomes.

Continue Reading


More in AFP

Copyright © 2006 by the American Academy of Family Physicians.

This content is owned by the AAFP. A person viewing it online may make one printout of the material and may use that printout only for his or her personal, non-commercial reference. This material may not otherwise be downloaded, copied, printed, stored, transmitted or reproduced in any medium, whether now known or later invented, except as authorized in writing by the AAFP.  See https://www.aafp.org/about/this-site/permissions.html for copyright questions and/or permission requests.