In The News: Take One Each Day

For years the American Heart Association has recommended an aspirin a day to help prevent a second heart attack. Now, scientists say, it may also help ward off colon cancer, at least in high-risk populations. Two major studies in The New England Journal of Medicine last week showed that a daily aspirin reduced the risk of adenomas--the type of polyps that can turn malignant--in patients who previously had adenomas or colorectal cancer.

But what dose is best? There is no clear answer. In the smaller of the studies, a daily full-strength aspirin (325 milligrams) reduced the incidence of new adenomas by about a third after 31 months. In the larger study, 325mg tablets were only marginally better than a placebo. The best results were seen in patients taking 81mg pills.

Is aspirin therapy for everyone? No, says internist and epidemiologist John Baron of Dartmouth Medical School, lead author of the larger study. Aspirin can cause internal bleeding, particularly in the stomach, so check with your doctor if you're going to take it regularly. And keep up routine colonoscopies if you're over 50. They're still a proven way to beat colon cancer.