(NaturalNews) The consumption of regular table grapes may lower blood pressure and improve heart health better than drugs, according to a study conducted by researchers from the University of Michigan Cardiovascular Center in Ann Arbor, and published in the Journal of Gerontology: Biological Sciences.
Researchers fed a powdered combination of green, red and black table grapes to lab rats there were consuming either a high- or low-salt diet. After 18 weeks, the cardiovascular health of these rats was compared to rats that had eaten either an equivalent diet supplemented with the blood pressure medication hydrazine rather than powdered grapes, or rats that had eaten the diet without any additions. All rats in the study were genetically predisposed to develop high blood pressure when fed a high-salt diet.
The researchers found that among the rats who were fed a high-salt diet, blood pressure was significantly lower among those whose diet had been supplemented with either hydrazine or grape powder.
"The inevitable downhill sequence to hypertension and heart failure was changed by the addition of grape powder to a high-salt diet," said researcher Steven Bolling. "Although there are many natural compounds in the grape powder itself that may have an effect, the things that we think are having an effect against the hypertension may be the flavonoids, either by direct antioxidant effects, by indirect effects on cell function, or both."
In addition, the rats that had eaten the grape powder had significantly less inflammation, better heart function and fewer indicators of damage to heart muscle than rats in either the control or hydrazine groups.
"These findings support our theory that something within the grapes themselves has a direct impact on cardiovascular risk, beyond the simple blood-pressure-lowering impact that we already know can come from a diet rich in fruits and vegetables," said researcher Mitchell Seymour of the University of Michigan Cardioprotection Research Laboratory.