The New Bottom Line on Your Daily Aspirin

Aspirin can be a life saver; it can reduce the risk of further heart attacks in people who have already had one and lower the risk of certain cancers.

That encouraging data led people to ask if the over-the-counter drug could also help prevent heart problems and cancer in the first place. In the latest study on the subject, published in the journal PLOS ONE, researchers led by Dr. David Agus at the University of Southern California Keck School of Medicine report that for older people, daily aspirin can lower the risk of heart attack and some cancers while leading to a longer life.

The model for the study is based on national databases about various health factors, from cancer incidence to rates of other chronic diseases, as well as body mass index and how functional people remain as they get older. The model also incorporates costs of health care for an aging population, and found that broader use of aspirin could save hundreds of thousands of lives and $692 billion in health care costs.

The results are the latest in the debate over whether aspirin should be used in healthy people to prevent a first heart attack, stroke, cancer or other health problem. Because aspirin helped prevent second heart attacks in people with heart disease, at first doctors recommended that those at high risk for heart problems start taking a low dose of aspirin every day. (At 80mg, that dose was much lower than the pain-killing doses that are typically three to four times higher.) Aspirin is a powerful anti-inflammatory agent, and researchers believe it can reduce the inflammation that can trigger heart attacks. In the case of cancer, the inflammation can cause damage that promotes abnormal cells like tumors to grow.

But in 2014, the Food and Drug Administration (FDA) deemed that such preventive doses in otherwise healthy people produced more risk than benefit. Aspirin, which works to reduce inflammation, activates enzymes that can irritate stomach and intestinal tissues, causing ulcers and bleeding. For people who haven’t yet had a heart attack, therefore, the FDA determined that the risk of such side effects were too great compared to the potential benefit they might get.

The American Heart Association (AHA) and the U.S. Preventive Services Task Force (USPSTF), a government-appointed panel of experts that studies large health questions, also have concerns about the drug’s side effects. But they continue to recommend the medication for a specific group of people who have not yet had a heart attack but who are at higher risk for one. They call for calculating an individual’s specific risk of developing heart disease in the next 10 years, based on a number of factors including their age, family history of heart trouble, blood pressure and cholesterol levels.

Despite that advice, however, 40% of men and 10% of women who fit those criteria and should be taking aspirin are not, according to the latest study. The authors also predict that if everyone who meets the conditions would take the drug as recommended, an estimated 900,000 more people would be alive by 2036. That’s because for every 1,000 people, 11 cases of heart disease and four cases of cancer would be averted.

So should everyone over age 50 start taking daily low-dose aspirin in order to live longer? Agus and his team also predicted what would happen under this scenario. The benefits of the drug have to be weighed against the fact that people who may avoid heart disease and add more years to their lives may also be more likely to develop cancer, diabetes or a disease of aging. The side effects of intestinal bleeding also have to be considered.

Still, Agus argues that at the very least, people who currently meet recommended criteria for taking aspirin—including those who are at higher risk of heart problems—should be taking the medication. “No matter how you look at it, the benefits are there. With [everyone taking it] the results are tempered, because other diseases happen, but clearly there is still benefit.”

The findings should push more people toward the AHA and USPSTF advice, which calls for people to discuss with their doctor their individual risk and benefit ratio, rather than deciding that aspirin is or isn’t right for them based on the drug’s label. “We can’t tell everybody over 50 what they should do,” says Agus. “The role of the physician is to explain risk and benefit and together with the patient make a decision.”