Grapes may lower blood pressure, aid heart

ANN ARBOR, Mich., Oct. 29 (UPI) -- Table grapes lowered blood pressure and signs of heart muscle damage while improving heart function in lab rats, U.S. researchers have learned.

Researchers at the University of Michigan Cardiovascular Center in Ann Arbor, Mich., studied the effect of regular table grapes -- a blend of green, red and black grapes -- that were mixed into the lab rats' diet in a powdered form, as part of either a high- or low-salt diet.

The researchers performed many comparisons between the rats consuming the test diet and the control rats receiving no grape powder -- including some which received a mild dose of a common blood-pressure drug. All the rats were from a research breed that develops high blood pressure when fed a salty diet.

After 18 weeks, the rats that received the grape-enriched diet powder had lower blood pressure, better heart function, reduced inflammation and fewer signs of heart muscle damage than rats that ate the same salty diet, but didn't receive grapes.

The study, published in the Journal of Gerontology: Biological Sciences, also determined rats that received the blood-pressure medicine, hydrazine, along with a salty diet also had lower blood pressure, but their hearts were not protected from damage as they were in the grape-fed group.