Should You Take Daily Aspirin to Prevent Heart Attacks?

✅ Yes or ❌ No: Skip down for the quick hits

• Aspirin guidelines have changed dramatically over the last 50 years

• Aspirin works by reducing the chance of forming blood clots

• An ncreased risk of bleeding needs to be balanced against protection

• A coronary artery calcium score can help determine if you should take aspirin

What is a heart attack?

A heart attack happens when accumulated lipids and inflammation in a blood vessel wall—an area of plaque—ruptures and exposes the internal contents of the arterial wall to the bloodstream. This activates platelets that form a partial (Non-ST Elevation) or complete (ST Elevation) blockage, commonly referred to as NSTEMI or STEMI—what we call a heart attack.

How did aspirin become a cornerstone cardiac medication?

Aspirin's origin story dates back at least 3,500 years to the Sumerians and Egyptians, who used willow bark as a fever reducer. Also known as acetylsalicylic acid, aspirin has been suspected to reduce platelets' ability to form clots since at least the 1950s, when Dr. Lawrence Craven published his first paper on the topic.

Dr. Craven was an Iowa native and 1914 graduate of the University of Minnesota College of Medicine. After serving in World War I, he moved to sunny Glendale, California, where he made prescient observations about aspirin's effects in reducing coronary disease in his patients.

It wasn't until 1988, with the publication of early results from the Physicians' Health Study, that aspirin for primary prevention (preventing someone's first heart attack) began to gain significant traction. The study enrolled over 20,000 male physicians and reported a 44% reduction in heart attack rates. From then on, the trend shifted toward much wider use of aspirin for primary prevention.

What changed and why the confusion now?

2018 was a bad year for "Big Aspirin." By the 2010s, data was mounting that widespread aspirin use was perhaps not as beneficial as the Physicians' Health Study suggested.

Key 2018 Studies:

• ARRIVE Study (The Lancet) - Moderate risk adults: increased GI bleeding with aspirin, no difference in heart attacks/strokes vs. placebo

• ASCEND Study (NEJM) - Diabetics without heart disease: 12% fewer vascular events with aspirin but 29% more bleeding episodes

• ASPREE Study (NEJM) - Adults 65+ without heart disease: aspirin group had no cardiovascular survival benefit, higher rates of bleeding and death, cancer, and cancer deaths vs. placebo (note: increased cancer was surprising—most other research suggests aspirin prevents cancer)

Importantly, these studies were in patients with no prior cardiac disease.

Consistent with this data, national guidelines began to shift, with multiple prominent medical societies weakening recommendations for primary prevention with aspirin. This change created uncertainty that persists today.

However, aspirin remains a cornerstone of cardiac prevention, especially after a heart attack—but selecting the right patient has become much more nuanced. Current guidelines from the US Preventive Services Task Force allow for considering aspirin for primary prevention in individuals ages 40-59 with a 10-year heart disease risk above 10%.

💡 So... Should You Be Taking Aspirin?

Let's break it down:

✅ Yes, daily aspirin (81 mg) if you have:

• Prior heart attack, stent, or bypass surgery

• Certain types of valve surgery

• A coronary calcium score >100 (especially >300), unless bleeding risk is high

🤔 Maybe, if:

• You're age 40–59

• Have a 10-year ASCVD risk ≥10%

• And you're not at high bleeding risk

❌ No, if:

• You're over 60 and haven't had a cardiovascular event

• You have low coronary calcium (<100)

• You're already on a blood thinner (like apixaban or warfarin for AFib)—in most cases, aspirin adds risk without benefit

🧪 Bonus Tip: Get a Coronary Calcium Score

It's a quick, inexpensive CT scan that measures plaque burden. If your score is 0, your 10-year heart attack risk is very low—and aspirin likely won't help. If it's high, you and your doctor may discuss low-dose aspirin as part of a broader prevention plan.

Were doctors wrong to recommend aspirin? Is this a symptom of medicine's flaws?

What changed from Dr. Craven's era to today? It probably wasn't the aspirin—it was everything else. Smoking rates are dramatically lower now compared to the past seven decades, and we have a better understanding of diet, exercise, and the importance of risk factos like LDL and Lipoprotein(a). Since at least the 1990s, we've gained huge preventive benefits from statins.

All these factors have changed the landscape and effectively plucked the low-hanging fruit of heart attack prevention. Aspirin remains important for many people, but we now have the chance to save many others from its potential ill effects.

🩺 Final Word

Aspirin still saves lives—but only when used wisely. It's no longer a blanket recommendation. Instead, it's about precision prevention: the right treatment, for the right patient, at the right time.

Before starting—or stopping—aspirin, talk to your doctor.

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As always, health is personal, and for personalized advice please consult your healthcare professional. Artificial Intelligence models may have used in research, formatting and editing of this post.