Mediterranean diet plus nuts lowers CV risk

An ad libitum Mediterranean-style diet, supplemented with daily serving of mixed nuts, appears to decrease the prevalence of metabolic syndrome in older people at high risk for cardiovascular disease, according to Spanish researchers.

In a one-year study, the diet also lowered the prevalences of hypertriglyceridemia and hypertension, two chief components of the metabolic syndrome. Those beneficial effects were achieved by dietary changes alone; the study subjects did not lose weight or increase their physical activity, said the University of Rovira I Virgili, Reus, Spain.

Traditionally, diets recommended to improve health are low in fat and calories, and “generally are not palatable,” the researchers said. The study’s results “show that a non-energy-restricted traditional Mediterranean diet enriched with nuts, which is high in fat . . . and palatable, is a useful tool in managing the metabolic syndrome.”

The PREDIMED (Prevencion con Dieta Mediterra-nes) study is an ongoing multicenter clinical trial involving approximately 9,000 older patients (aged 55-80 years) who are at high risk for cardiovascular disease but as yet show no sign of it.

A subgroup of 1,224 patients was assessed for the report. They were randomly assigned to follow a Mediterranean-style diet supplemented with mixed nuts (primarily walnuts, hazelnuts, and almonds), a Mediterranean-style diet supplemented with virgin olive oil, or a control group.

A total of 61 percent of the subjects met the criteria for metabolic syndrome, and nearly 45 percent had type 2 diabetes, the investigators reported.

After one year, the rates of elevated triglycerides, high blood pressure, and abdominal obesity were significantly decreased with both dietary interventions, but were not in the control group. Those reductions were more pronounced in the group that followed the Mediterranean-style diet supplemented with nuts.

The overall prevalence of the metabolic syndrome decreased by 14% in the diet-plus-nuts arm of the trial, and by 7 percent in the diet-plus-olive oil arm, compared with a 2 percent reduction in the control group.

“The novelty of our findings is that a positive effect on the metabolic syndrome was achieved by diet alone, in the absence of weight loss or increased energy expenditure in physical activity.”

Longer follow-up in the study, which is designed to continue for another three years, may provide stronger evidence of the cardiovascular benefits of the Mediterranean diet, the investigators added.