For people with cardiovascular disease (CVD), a daily aspirin reduces the risk of heart attack , stroke , or other serious events. In CVD, plaque build-up in the arteries—called atherosclerosis—can block blood flow and rob the heart and brain of oxygen. Plaques are particularly dangerous because they are often associated with the formation of clots, which can completely block flow to these vital organs, leading to heart attacks and strokes. Aspirin, even in small doses, makes it more difficult for blood to clot. Studies suggest that even presumably healthy men can benefit from taking aspirin. There is less data on the benefits for women.

So, aspirin is good for the gander, but what about the goose? It’s good for her, too, according to a study in the January 18, 2006 Journal of the American Medical Association . By combining data from the best studies to date, the researchers found that both sexes benefit from daily aspirin, but in different ways. In women, aspirin reduced the risk of stroke; in men, heart attack. In both sexes, however, aspirin increased the risk of bleeding.

About the Study

The researchers scoured scientific databases for studies that evaluated the preventive merit of aspirin for people without CVD. Based on strict criteria, six studies were selected, representing a total of 51,342 women and 44,114 men, all free of known CVD, who were given aspirin and monitored for an average of 6.4 years. Researchers tallied the number of strokes, heart attacks, and deaths due to CVD, as well as bleeding episodes. Rates for women and men were compared.

Aspirin was associated with significant benefits: for men, a 32% reduction in heart attack, and for women, a 17% reduction in stroke (mainly ischemic stroke, due to a blocked artery). These benefits are not without risks. Aspirin caused a 70% increase in the risk of major bleeding events such as gastrointestinal bleeding. This translates to 2.5 events per 1,000 women and 3 per 1,000 men over 6.4 years of aspirin therapy. Men also had a significant rise in the risk of hemorrhagic stroke, which occurs when a small artery in the brain bursts and bleeds.

This analysis is limited by the differences of the six studies. Each had a slightly different protocol for aspirin therapy and brought with it its own limitations. Also, the total number of CVD events was fairly low, due to the low risk of the study population. Larger trials on people at higher risk are necessary.

How Does This Affect You?

Should an aspirin a day replace an apple a day? Not quite. This study suggests that aspirin is a good tool for lowering the risk of stroke (for women) and heart attack (for men). However, the increased incidence of bleeding should not be overlooked. This risk underscores the need to discuss the benefits and drawbacks of aspirin therapy with your doctor in relation to your own personal health needs.

With or without aspirin, everyone can take steps towards a heart healthy lifestyle. These behaviors have been shown to reduce the risk of CVD and have no dangerous side effects:

  • Eat a diet rich in fruits, vegetables, whole grains, and fish
  • Limit the amount of saturated and trans fat and cholesterol that you eat
  • Be physically active daily
  • If you smoke, quit
  • Identify and reduce stress