Countless studies on grape seed extract suggest of its exceptional source of polyphenols and oligomeric proanthocyanidins (OPC), antioxidants that help protect cells from free radical damage and also promotes healthy circulation. OPC is touted to be more powerful than vitamin C, E, and Beta-carotene.

Grape seed extract is said to remain in the body for three full days compared to other sources which are excreted by the body shortly after ingestion. It is also more potent than vitamin C, and also 50 times stronger than vitamin E.

In a recent study, grape seed extract is found to have potential in curbing leukemia. When researchers exposed human leukemia cells to grape seed extract in test tubes, 76% of the leukemia cells died within 24 hours, with the normal cells getting spared.

According to Xianglin Shi, PhD, everyone seeks an agent that has an effect on cancer cells but leaves normal cells alone. And grapeseed extract meets the requirement. But while the experiment seemed very promising, Shi said that it's still in its early stages.

Grape seed extract has been tested in a number of laboratory cancer cell lines, including skin, breast, colon, lung, stomach and prostate cancers. In 2006, chemicals found in grape seeds significantly inhibited growth of colorectal tumors in both cell cultures and in mice.

As Shi's team searched for clues on how grape seed extract hastens leukemia cell death, they found several proteins that the grape seed extract apparently affected. Shi and colleagues consider those proteins as "attractive targets."

While Shi's study isn't making any recommendations about grape seed extract for leukemia patients, their findings may have implications for adding grape seed extract/other agents to chemotherapy/other therapies for leukemia and perhaps also for other blood cancers.