Many of us have considered a daily low-dose aspirin a smart health move—for years, we’ve been told it can prevent a heart attack or stroke.

But in the last week, there’s been a reversal of that thinking. Taking a 75 to 100 milligram pill is no longer recommended for most older adults, according to the American College of Cardiology and the American Heart Association. 

Why the big change of heart (sorry, not sorry for the pun)? A large clinical trial found a daily low-dose aspirin had zero effect on prolonging life in healthy older people—and actually seemed to suggest the pills could be linked to major hemorrhages.

Here’s how aspirin works: It interferes with your blood’s clotting action. Usually, when you bleed, platelets—the clotting cells—help form a “plug” that seals an opening in a blood vessel to help stop the flow. But if this clotting happens in the blood vessels that supply the heart and if those passageways are narrowed due to atherosclerosis (the buildup of fatty deposits in your arteries), you can wind up in trouble. If a fatty deposit in the lining of the vessel bursts, a blood clot can form, block the artery, and trigger a heart attack. Aspirin therapy reduces the clotting action of those platelets and, it was thought, would help patients avoid that life-threatening situation.  

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Is Aspirin Good for You? The Real Story

One less pill for us to swallow. Image: Dmitry Bayer/Unsplash

But while this theory makes sense, it hasn’t been found to actually pay off in real life. Now, the word is that low-dose aspirin should not be given routinely to adults age 70-plus or to anyone who is at increased risk of bleeding.

Call out: New guidelines say that doctors should be very selective in prescribing aspirin for people without known cardiovascular disease.

“Clinicians should be very selective in prescribing aspirin for people without known cardiovascular disease,” cardiologist Roger Blumenthal MD, FACC, co-chair of the 2019 ACC/AHA Guideline on the Primary Prevention of Cardiovascular Disease, commented in a statement. “It’s much more important to optimize lifestyle habits and control blood pressure and cholesterol as opposed to recommending aspirin.”

So if you have been taking aspirin to benefit your heart, check in with your doctor. And continue to do all the right stuff—like getting regular exercise, maintaining a healthy weight, avoiding tobacco, and eating a diet rich in vegetables and low in sugar and trans fats—to keep cardiovascular disease in check.

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