Find Information About:

Drugs & Supplements

Get information and reviews on prescription drugs, over-the-counter medications, vitamins, and supplements. Search by name or medical condition.

Pill Identifier

Pill Identifier

Having trouble identifying your pills?

Enter the shape, color, or imprint of your prescription or OTC drug. Our pill identification tool will display pictures that you can compare to your pill.

Get Started

My Medicine

Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more.

Get Started

WebMD Health Experts and Community

Talk to health experts and other people like you in WebMD's Communities. It's a safe forum where you can create or participate in support groups and discussions about health topics that interest you.

  • Second Opinion

    Second Opinion

    Read expert perspectives on popular health topics.

  • Community


    Connect with people like you, and get expert guidance on living a healthy life.

Got a health question? Get answers provided by leading organizations, doctors, and experts.

Get Answers

Sign up to receive WebMD's award-winning content delivered to your inbox.

Sign Up

Colorectal Cancer Health Center

Font Size

Grape Seed Extract vs. Colon Cancer

Lab Tests in Mice Show Promise in Fighting Colon Cancer, but More Research Needed
WebMD Health News
Reviewed by Louise Chang, MD

Oct. 19, 2006 -- Grape seed extract may pack a punch against colon cancer, early lab tests show.

But the researchers -- who work at the University of Colorado -- aren’t making any promises yet.

"The value of this preclinical study is that it shows grape seed extract can attack cancer, and how it works, but much more investigation will be needed before these chemicals can be tested as a human cancer treatment and preventive," says Rajesh Agarwal, PhD, one of the researchers.

"With these results, we are not suggesting that people run out and buy and use grape seed extract," Agarwal says in a news release from the American Association for Cancer Research. "That could be dangerous since so little is known about doses and side effects."

Testing the Extract

In their study, the researchers began by testing various doses of grape seed extract on human colon cancer cells in test tubes.

The cancer cells treated with grape seed extract were more likely to halt their normal growth cycle and die, compared to those not treated with the extract.

Cancer cells that got the biggest doses of grape seed extract for the longest time were the most likely to halt their growth cycle.

Those results were "encouraging," the researchers write.

So the scientists took their experiment one step further.

They injected human colon cancer tumors under the skin of mice, then funneled grape seed extract into the mice’s mouths through a tube.

The tumors grew more slowly in those mice, compared to the tumors in mice that didn’t get grape seed extract.

The mice that got grape seed extract didn’t gain weight, change their diets, or show other side effects during the eight-week study.

Agarwal and his colleagues write that antioxidants called proanthocyanidins may be responsible for grape seed extracts’ effects.

Today on WebMD

Colorectal cancer cells
The right diagnosis is the most important factor.
man with a doctor
Our health check will steer you in the right direction.
sauteed cherry tomatoes
Fight cancer one plate at a time.
bladder cancer x-ray
Do you know the warning signs?
Colon vs Rectal Cancer
New Colorectal Treatments
can lack of sleep affect your immune system
Cancer Facts Quiz
Virtual Colonoscopy
Picture of the Colon
Vitamin D