Short answer: for most healthy adults with no history of heart attack or stroke, daily low-dose aspirin is no longer routinely recommended, because the risk of internal bleeding tends to outweigh the modest protective benefit. The calculation is different for people who already have cardiovascular disease. This is a decision to make with your doctor, not one to start or stop on your own.

What Changed: The Guidance on Aspirin Has Shifted

For decades, many people were told that a daily "baby aspirin" was a simple, low-cost way to protect the heart. That advice has changed. The US Preventive Services Task Force (USPSTF), an independent panel of experts that reviews evidence to guide preventive care in the United States, now recommends against starting daily aspirin for most adults age 60 and older who have never had a heart attack or stroke, and it says the decision should be individualized for adults ages 40 to 59 who have a higher calculated cardiovascular risk. The shift happened because newer, larger studies showed that the small reduction in heart attacks and strokes was largely offset by an increase in serious bleeding, particularly in the stomach, intestines, and brain.

Primary Prevention vs Secondary Prevention: Why It Matters

The single most important distinction in this decision is whether you already have cardiovascular disease.

• Primary prevention: Taking aspirin to try to prevent a first heart attack or stroke in someone who has never had one. This is the group where guidance has shifted away from routine use.
• Secondary prevention: Taking aspirin after someone has already had a heart attack, ischemic stroke, stent, or bypass surgery, to help prevent a second event. In this group, the benefit of aspirin is well established and generally outweighs the bleeding risk, so daily aspirin usually continues unless a doctor says otherwise.

Who May Still Be a Candidate for Primary Prevention Aspirin

The USPSTF notes that a small, select group of adults ages 40 to 59 with a 10-year cardiovascular risk of 10 percent or higher, and no increased bleeding risk, may reasonably choose to start low-dose aspirin after discussing it with a clinician. Your doctor calculates that 10-year risk using factors like your age, blood pressure, cholesterol, smoking status, and diabetes history. This is not a decision to estimate yourself; it depends on a formal risk calculation done in a clinical setting.

Who Should Generally Avoid Daily Aspirin for Prevention

• Adults age 60 and older with no history of cardiovascular disease, according to current USPSTF guidance
• Anyone with a history of stomach or intestinal ulcers, or prior gastrointestinal bleeding
• People taking other blood thinners or anticoagulants, unless a doctor is specifically coordinating that combination
• People with a bleeding disorder or a history of hemorrhagic stroke
• Anyone with uncontrolled high blood pressure, since this raises the risk of bleeding, including in the brain
• People with significant kidney or liver disease, without medical guidance

Regular alcohol use also raises the bleeding risk associated with aspirin and should be discussed with your doctor if you are considering it.

Weighing Benefits Against Risks

Aspirin works by making platelets less likely to clump together and form a clot, which is the mechanism behind both its heart-protective effect and its bleeding risk. In people without existing heart disease, that clot-preventing effect modestly lowers the chance of a first heart attack, but the same mechanism raises the chance of bleeding events, some of which can be serious. For most healthy adults, the two effects are close enough in size that the balance tips toward avoiding routine use, which is why this is no longer a blanket recommendation and instead needs to be personalized.

Practical Takeaways

• If you already have heart disease, a stent, or a history of stroke, do not stop aspirin without talking to your doctor first.
• If you do not have heart disease and are not currently taking aspirin for prevention, most guidelines no longer suggest starting it on your own.
• If you are already taking daily aspirin for prevention and are unsure why, bring it up at your next appointment so your doctor can confirm whether it still makes sense for you.
• Never combine aspirin with other blood thinners, ibuprofen, or naproxen without medical guidance, since combinations raise bleeding risk.

When to Seek Medical Care