The traditionally Mediterranean diet is characterised by a high intake of olive oil, fruit, nuts, vegetables and whole-grain products; moderate consumption of fish, white meat and red wine at meal times and limited consumption of red meat and sweets. Observational studies have already shown an inverse correlation between a Mediterranean diet and the risk of cardiovascular disease.
The study specific to Estruch et al. (2013) examined the connection between a Mediterranean diet and the primary prevention of cardiovascular inflammation. Subjects belonging to a cardiovascular risk group were randomised, these subjects being free from inflammation at the time of the study. The study population comprised a total of 7,447 persons (aged from 55 to 80), 57% of them being women. The three study groups differed as follows: the first group partook of a Mediterranean diet incorporating extra-virgin olive oil; the second group supplemented the Mediterranean diet with mixed nuts and the third group followed a control diet (reduction in dietary fat).
On the basis of the results of an interim evaluation, the study was discontinued after a period of four years and eight months. A primary end-point (e.g. stroke, heart attack or death attributed to cardiovascular causes) occurred in 288 participants. The statistical evaluation shows significant differences between the groups: in group 1 (incorporating extra-virgin olive oil) a primary end-point occurred in 96 subjects; in group 2 (incorporating nut consumption), only 83 cardiovascular events occurred, whereas 109 subjects evinced primary end-points in the control group. During the entire study phase, none of the diets exerted undesirable effects on the subjects.
In conclusion, the long-term study shows that in persons presenting with high cardiovascular risk, the incidence of serious cardiovascular events is reduced when supplemented by a Mediterranean diet incorporating extra-virgin olive oil or nuts. Thus, the results confirm the hypothesis that a Mediterranean diet is suitable for the primary prevention of cardiovascular events.
Estruch R et al. (2013): Primary prevention of cardiovascular disease with a mediterranean diet. N Engl J Med, DOI:10.1056.