Over the past few years we have been hearing about the anti-oxidising effect of the Mediterranean diet, however until now there have been no reliable scientific studies carried out to prove this. A team of IMIM-Hospital del Mar researchers consisting of Drs. Montserrat Fitó, Rafael de la Torre, Jaume Marrugat under the supervision of Dr. María Isabel Covas, have taken on the task.

The work entitled “Effect of a Traditional Mediterranean Diet on Lipoprotein Oxidation” which has been published in the Archives for International Medicine on the 11th of June shows for the first time the anti-oxidising benefits of the Mediterranean diet. The results of the study contain strong evidence recommending people at high risk of cardiovascular disease to adopt a more Mediterranean diet to prevent coronary heart disease.

In arriving at these conclusions the research team studied 372 people (210 women and 162 men) in the 55-80 age category with a high risk of cardiovascular disease; high risk being defined as people who, although not necessarily presenting symptoms at this time, have at least one of the following: diabetes, hypertension, dyslipidemia, obesity and family history of heart disease. All the subjects agreed to participate in the PREDIMED study (acronym for Prevention with Mediterranean Diet) which is a controlled and randomised comparative study, carried out on parallel groups, designed to detect significant differences between the groups participating in the study. The main variable considered in this primary analysis of the study was the observation of the level of in vivo oxidation of lipids, these days considered as a very important risk factor for arteriosclerosis.

Each of the participants where chosen at random - with no characteristics taken into consideration (sex, age and physical condition) that may interfere with the results – to follow one of the three types of diet proposed in the study. As such, 121 people were assigned to a low-fat diet; 128 followed a Mediterranean diet, rich in fruit, vegetables and fish with an olive oil supplement; and, finally, the third group went on a Mediterranean diet enriched with nuts. Urine analysis was carried out to ensure that each person kept to the diet assigned to them.

The results showed that the level of oxidation of lipids was unaltered in people on a low fat diet but was significantly reduced in the group with a high level of olive oil in their diet.

These are the first of the results obtained from the PREDIMED study, a project involving 9000 people in total, in ten Spanish health centres with the main objective of providing evidence of the beneficial effects of the Mediterranean diet through observing 930 people at risk of coronary heart disease over a period of four years.

Source: IMIM-Hospital del Mar