Grapeseed Extract Protects Against Atherosclerosis
A study published in the journal Atherosclerosis showed that a small amount of grapessed extract added to animals’ diets prevented aortic atherosclerosis and may well protect against heart disease in humans.
The results were reported by researchers at the R&D Division of Kikkoman Corporate and the Noda Institute for Scientific Research, in Japan.
They added grapeseed extracts, rich in the class of polyphenols known as proanthocyanidins, to rabbits’ diets. The animals were divided into groups of eight and fed either standard rabbit chow, chow with atherosclerosis-indusing cholesterol, chow with cholesterol plus 1.0 percent grapseed proanthocyanidin, and chow with cholesterol plus 0.1% grapeseed proanthocyanidin.
At the end of the study, when they examined the rabbits’ aortas, researchers found that although grapeseed did not affect the animals’ serum cholesterol levels it considerably lowered cholesterol in the aortic wall. Even more significantly, animals fed the proanthocyanidin suplement had less atherosclerotic plaque in their aortas. The aortas of the animals fed grapeseed also contained fewer oxidized smooth muscle cells--indicators of atherosclerosis.
Somewhat surprising, results were not significantly different between the 0.1% and the 1.0% proanthocyanidin groups. This may be because in the rabbits, only a certain amount of the material is absorbed, no matter much is eaten.
Proanthocyanidins are powerful wateer-soluble antioxidants. They are thought to trap reactive oxygen compounds in the plasma and cells of the artery walls before they can damage low density lipoprotein (LDL) cholesterol.
Proanthocyanadins concentrate in artery walls, so small doses usually suffice--the researchers extrapolate that about 1.25 grams would be adequate for a 110 lb person.
Their conclusion: "Procanthocyanidin-rich foods such as red wine and health foods containing grapeseed extract may be beneficial in lowering the incidence of atherosclerosis and coronary heart disease.
(Atherosclerosis 1999 Jan; 142(1):139-49)