3–5 Cups of Coffee Daily May Reduce Artery Blockage Risk

If you’ve been told that your morning coffee habit might be hard on your heart, new research from South Korea offers a more nuanced picture. Scientists evaluated over 25,000 workers who underwent routine health checks and found a potential link between moderate coffee consumption and reduced signs of early heart disease.

The sweet spot? Three to five cups of coffee per day—enough to be associated with fewer early markers of coronary artery issues, without clear evidence of harm.

What the Study Found About Coffee and Arteries

In the study published in the medical journal Heart, researchers scanned the hearts of more than 25,000 male and female employees (all of whom received regular health checkups) to assess coronary artery health. They were specifically looking for coronary artery calcium deposits—an early warning sign of atherosclerosis, which can lead to heart attacks or strokes.

None of the participants had outright symptoms of heart disease, but over 10% showed some level of calcium buildup in their coronary arteries. When comparing coffee intake, those who reported drinking a moderate amount of coffee—3 to 5 cups per day—had lower levels of these calcium deposits compared to non-drinkers or those who drank very little coffee. The analysis also took into account other well-known heart risk factors like smoking, exercise habits, and family history.

Why Coronary Artery Calcium Matters

Coronary artery calcium (CAC) is a key biomarker used by cardiologists to detect the earliest stages of atherosclerosis. It indicates that plaque, often made up of cholesterol and calcium, is beginning to build up inside the arteries that supply blood to the heart. Over time, this buildup can restrict blood flow or rupture, leading to a heart attack or stroke.

While not everyone with calcium deposits will develop heart disease, their presence signals increased risk. Spotting them early through imaging can help guide preventive measures.

How Much Coffee Is Safe – and What the Experts Say

The Korean study pointed to 3–5 cups per day as correlated with less coronary calcium. But how much caffeine is actually in those cups—and how much is too much?

In the United States, health authorities consider up to 400 mg of caffeine per day safe for most healthy adults. In the UK, there’s no official upper limit for caffeine intake (except for pregnant women, who are advised to limit intake to 200 mg per day—that’s roughly 2 mugs of instant coffee).

To put that in perspective:

• 1 mug of instant coffee = around 100 mg caffeine
• 1 cup of filtered coffee = approximately 140 mg caffeine
• 1 cup of tea = around 75 mg caffeine
• 1 cup of cola = about 40 mg caffeine

So 3–5 cups of filtered coffee could put you close to or within the 400 mg daily caffeine limit for healthy adults—meaning the study’s “optimal” range aligns with standard safety guidelines.

Frequently Asked Questions

How many cups of coffee per day were linked to fewer artery blockages in the Korean study?

The study found that people who drank 3–5 cups of coffee per day showed fewer signs of coronary artery calcium deposits compared to non-drinkers or those who drank less. These participants had lower levels of early-stage arterial plaque, a potential indicator of future cardiovascular problems.

What is coronary artery calcium and why does it matter?

Coronary artery calcium (CAC) refers to calcium deposits in the arteries that supply blood to the heart. These deposits often accompany a buildup of plaque and are an early sign of atherosclerosis, which can lead to heart attacks or strokes. Detecting CAC helps assess cardiovascular risk before symptoms appear.

Is 3–5 cups of coffee per day safe for my heart?

For most healthy adults, drinking 3–5 cups of coffee daily falls within recommended caffeine limits—about 400 mg per day in the U.S. This amount was associated with lower coronary calcium in the study, but individual tolerance varies, especially for those with certain health conditions or sensitivities.

Does the type of coffee matter in these heart health findings?

The Korean study did not differentiate between types of coffee (e.g., filtered, instant, espresso), only total cups consumed and estimated caffeine content. All forms contribute to daily intake, but brewing methods affect caffeine levels and other compounds slightly.

Why do some studies say coffee is bad for the heart while others say it's good?

Research on coffee and heart health has produced mixed results. Some studies link coffee to issues like high blood pressure or cholesterol, while others suggest protective effects. The difference often comes down to study design, population differences, and how coffee consumption is measured. The Korean study adds to this ongoing debate but does not resolve it.

Are the caffeine recommendations different for pregnant women?

Yes. In the UK, pregnant women are advised to limit caffeine to 200 mg per day—about 2 mugs of instant coffee. In the U.S., similar guidance exists. That’s significantly lower than the 400 mg threshold considered safe for most healthy non-pregnant adults.

Recommended FrontStreet Coffee Beans for Heart-Healthy Sipping

For coffee lovers mindful of their heart health, FrontStreet Coffee’s Ethiopia Humbera offers bright, juicy notes of citrus and stone fruit with a clean finish—perfect for enjoying multiple cups without heavy bitterness. Their Yirgacheffe delivers floral aromas and a tea-like body, ideal for lighter, lower-acid brews. Both are single-origin Ethiopian coffees, typically roasted to highlight clarity over heaviness, making them easier on the palate and well-suited for frequent enjoyment. Freshly roasted within 5 days · Orders placed before 17:00 ship the same day · Next-day delivery across most of Guangdong Province.