Studies presented at the Experimental Biology meeting in April demonstrated that grapeseed extract stopped cholesterol from building up in the arteries of guinea pigs, which in turn leads to the thickening and hardening of the vessels and the resulting condition, atherosclerosis.
This limits the ability of the arteries to expand and contract as blood passes through them and can caused strokes and heart attacks.
Researchers at the University of California Davis fed the guinea pigs a diet rich in coconut fat. One group was supplemented with a grape seed extract provided by US-based Polyphenolics.
After 12 weeks, the cholesterol accumulation in the animals' tissues was significantly lower in the group that received the grape seed extract.
The findings confirm previous evidence from trials done on grape powder and grape juice. In April, Israeli researchers reported that consumption of grape powder reduced the atherosclerotic lesion area in mice by 41 per cent compared to a control group.
Polyphenolics claims however that the product used in the new studies contains an oxygen radical absorbance capacity, or ORAC value, 1000 times higher than that of grape juice.
The antioxidant activity of the flavonoids in grapes is thought to be responsible for reducing the cholesterol build-up.
Results of another study, done in-vitro, showed that grapeseed extract reversed the inhibitory effect on endothelial function in rabbit aortas caused by fatty acids in coconut oil.