Millions of Americans take aspirin daily to prevent blood clots, heart attack and stroke. But are they taking too much?

A recent study by researchers at the University of Kentucky suggests that a 325 mg dose of adult aspirin is not more effective than an 81 mg dose of baby aspirin but carries a higher risk for bleeding of the gastrointestinal tract.

A review of the published data found no benefit to higher doses of aspirin and cited the dangers of bleeding as a reason for patients to take the lowest effective dose. According to Dr. Steve Steinhubl, one of the study’s authors, there is almost no one who needs to take more than 81 mg of aspirin a day but cautions patients to check with their doctors to be sure.

UK Study: Baby Aspirin Better for Your Health

The old stand-by drug, aspirin, has been replaced in many medicine cabinets by other pain-killers and headache and fever reducers. Due to its effect on the lining of the stomach and the risk of bleeding and ulcers, aspirin is generally taken regularly only by those with a risk of heart disease.

But researchers have found evidence in test-tube experiments that aspirin has angiogenesis-blocking power, that is, it keeps cancers from creating the blood vessels they need to grow. They caution that these tests have not been done in humans yet and that no one should start taking aspirin to ward off cancer.

Aspirin May Be Newest Cancer Drug - WebMD