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

Aspirin May Lower Women's Colon Cancer Risk

Benefit must be weighed against GI bleeding, other risks, however, experts say

WebMD News from HealthDay

By Kathleen Doheny

HealthDay Reporter

MONDAY, July 15 (HealthDay News) -- Taking a low-dose aspirin every other day may reduce the risk of colorectal cancer, according to a study that focused on nearly 40,000 women aged 45 and older.

The protection does seem to take some time to surface, said researcher Nancy Cook, a professor of medicine at Brigham and Women's Hospital and Harvard Medical School. "After 10 years, we started to see an effect," she noted.

"After 18 years of follow-up, we saw a 20 percent reduction in colon cancer over the whole time period," she said. When they looked at the 10-to-18 year mark, the reduction was 42 percent, she said.

However, risks linked with aspirin, such as gastrointestinal bleeding, must be considered, Cook said.

The study, funded by the U.S. National Cancer Institute and U.S. National Heart, Lung, and Blood Institute, is published July 16 in the Annals of Internal Medicine.

Aspirin has been long known for its protective effects on heart health, but the protective effect of aspirin on colon and rectal cancer has only been found more recently. "In the past three years, analyses of trials conducted for cardiovascular health have begun to show an effect on colon cancer as well," Cook said.

Cook and her team followed women enrolled in the Women's Health Study, a trial that evaluated the benefits and risks of low-dose aspirin and vitamin E in preventing both cardiovascular disease and cancers.

The study began in 1993 and ended in 2004. The women had no history of cancer (except nonmelanoma skin cancer), cardiovascular disease or other major chronic illness when they enrolled.

The women assigned to the aspirin group were told to take a low dose -- 100 milligrams -- of aspirin every other day. The comparison group took placebo pills on alternate days.

After the study ended, the researchers continued to follow more than 33,000 women through March 2012. The women were told to continue the regimen, although the researchers no longer provided the pills.

The researchers tracked colorectal cancer, along with other cancers. They found the 20 percent lower colorectal cancer incidence over the entire 18-year follow-up.

1 | 2 | 3

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