Aspirin disappoints for avoiding first heart attack, stroke

Taking a low-dose aspirin every day has long been known to cut the chances of another heart attack, stroke or other heart problem in people who already have had one, but the risks don't outweigh the benefits for most other folks, major new research finds.

Although it's been used for more than a century, aspirin's value in many situations is still unclear. The latest studies are some of the largest and longest to test this pennies-a-day blood thinner in people who don't yet have heart disease or a blood vessel-related problem.

One found that aspirin did not help prevent first strokes or heart attacks in people at moderate risk for one because they had several health threats such as smoking, high blood pressure or high cholesterol.