OTTAWA, Ontario — October 14, 2014 — For people with metabolic syndrome, a Mediterranean diet supplemented with extra-virgin olive oil or nuts may help reverse the condition, according to a study published in the Canadian Medical Association Journal.
Researchers analyzed data from the PREDIMED randomized controlled trial, which included men and women aged 55 to 80 years who were at high risk of heart disease. Participants were randomly assigned to 1 of 3 diets: a Mediterranean diet supplemented with extra-virgin olive oil, a Mediterranean diet supplemented with nuts, or a low-fat diet as the control.
In the current analysis, the researchers team looked at the long-term effects of the Mediterranean diet on metabolic syndrome in 5,801 people. Almost 64% (3707) of the participants had metabolic syndrome at the start of the study.
After a median follow-up period of 4.8 years, the researchers found that people in the 2 Mediterranean diet groups decreased their central obesity and blood glucose levels and 958 participants (28.2%) no longer met the criteria of metabolic syndrome.
“In this large, multicentre, randomized clinical trial involving people with high cardiovascular risk, a Mediterranean diet supplemented with extra-virgin olive oil was associated with a smaller increase in the prevalence of metabolic syndrome compared with advice on following a low-fat diet,” wrote Jordi Salas-Salvadó, MD, Universitat Rovira i Virgili and Hospital Universitari de Sant Joan de Reus, Reus, Spain, and colleagues.
“Because there were no between-group differences in weight loss or energy expenditure, the change is likely attributable to the difference in dietary patterns.”
However, the Mediterranean diets did not appear to have an effect on the number of new cases of metabolic syndrome, a finding inconsistent with some previous studies.
“Mediterranean diets supplemented with olive oil or nuts were not associated with a reduced incidence of metabolic syndrome compared with a low-fat diet; however, both diets were associated with a significant rate of reversion of metabolic syndrome,” the authors wrote.
SOURCE: Canadian Medical Association Journal