Researchers from the University of Connecticut found that consuming grapes can lead to a reduction in key risk factors for heart disease in men with metabolic syndrome: reduced blood pressure, improved blood flow and reduced inflammation.
Natural components found in grapes, known as polyphenols, are thought to be responsible for these beneficial effects.
Metabolic syndrome is a cluster of conditions that occur together - increased blood pressure, a high blood sugar level, excess body fat around the waist or low HDL (the good cholesterol) and increased blood triglycerides – significantly increasing the risk for heart disease, stroke and diabetes.
The study recruited men between 30 and 70 years of age with metabolic syndrome. Participants were randomly assigned to consume grapes, in the form of a freeze-dried whole grape powder, or a placebo powder, for four weeks.
Then, following a 3-week "washout" period where neither grapes nor placebo were consumed, individuals were allocated to the alternate treatment. This allowed investigators to compare the response of each individual to consumption of both the placebo and grapes.
The study showed that for each of the study`s subjects, grape consumption resulted in significant decreases in blood pressure, improved blood flow (greater vasodilation), and decreases in a compound associated with inflammation.
"This further supports the accumulating evidence that grapes can positively influence heart health, and extends it to men with metabolic syndrome," principal investigator Dr Maria Luz Fernandez from the University said in a statement. The study was published in the Journal of Nutrition.