- A daily cup of coffee lowered the risk of atrial flutter (AF) returning after treatment.
- Coffee drinkers in the study had a 39% lower risk of recurrence than those who avoided caffeine.
- The study looked at AF recurrence, not prevention, and used everyday coffee—not high-dose caffeine.
A new study suggests that drinking a cup of coffee every day may actually lower the risk of atrial fibrillation returning in people who’ve recently been treated for it.
The findings suggest that coffee may be safer than once believed for people recovering from atrial fibrillation—a condition that affects more than 2 million adults in the United States and is one of the most common types of arrhythmias—and could even offer some protection from rhythm problems coming back.
Atrial fibrillation happens when the upper chambers of the heart, or atria, beat rapidly and irregularly, which keeps them from emptying properly. It becomes more common with age and is often linked to factors like high blood pressure, heart disease, inflammation, sleep apnea and alcohol use. Because atrial fibrillation can raise the risk of stroke and other complications, it’s understandable that many people want to lower their chances of having it return.
For years, people with atrial fibrillation have been told to avoid caffeine because it was thought to set off those irregular heartbeats. But new research published in JAMA suggests the opposite may be true, offering early evidence that typical coffee consumption might not be the trigger it was once believed to be.
How Was the Study Conducted?
To find out whether coffee helps or harms, researchers launched the DECAF study (Does Eliminating Coffee Avoid Fibrillation?), the first randomized trial to test caffeinated coffee’s link to AF.
The study team enrolled 200 adults with a history of persistent atrial fibrillation or atrial flutter—a related rhythm disorder where the atria beat very fast in a more organized pattern—who were scheduled to have cardioversion, a procedure that helps reset the heart’s rhythm. Everyone in the study was a current or recent coffee drinker, which allowed the researchers to look at caffeine’s effects in people who were already used to it.
Participants were recruited from five hospitals in the U.S., Canada and Australia and then randomly assigned to either drink at least one cup of caffeinated coffee a day or avoid caffeine altogether. The researchers followed the participants for six months to see whether anyone’s heart rhythm issues came back.
What Did the Study Find?
By the end of the six-month follow-up, the participants who kept drinking at least one cup of caffeinated coffee a day had fewer repeat episodes of atrial fibrillation or atrial flutter than those who avoided caffeine.
Atrial fibrillation or flutter recurrence happened in 47% of the coffee group, while 64% of the group that abstained from caffeine experienced recurrence. That translates to a 39% lower risk of recurrence for those who kept drinking coffee. A similar benefit of coffee was observed when the researchers looked at atrial fibrillation alone (without atrial flutter).
How Does This Apply to Real Life?
The DECAF researchers can’t say for sure why coffee seemed to help, but they have a few ideas. Caffeine blocks certain receptors in the body that normally make it easier for atrial fibrillation to start, so this blocking effect may help steady the heart’s electrical activity. Coffee also has natural anti-inflammatory properties and since inflammation can raise the risk of atrial fibrillation returning, reducing it may offer some protection.
There may be indirect reasons too. The study team noted that in previous research, people who were encouraged to drink coffee ended up moving more throughout the day, and physical activity is known to support a healthy heart rhythm. Still, before you start reaching for another cup of joe, it’s important to consult with a healthcare professional before you make a change—especially if you’ve experienced atrial fibrillation and want to make the safest, heart-healthiest choice for you.
It’s important to note that this study looked at everyday coffee drinking, not large doses of caffeine or energy drinks, and it only examined atrial fibrillation recurrence in people who already had the condition. It does not show whether coffee can prevent atrial fibrillation in people who’ve never had it.
Our Expert Take
The DECAF study pushes back on a common warning given to people with atrial fibrillation—that caffeine should be avoided at all costs. The evidence here suggests the opposite: for many patients, a daily cup of coffee may actually support rhythm stability rather than disrupt it. And because the benefit came from typical coffee drinking, not high-dose caffeine, it offers a reassuring message for anyone who’s been sidelining their morning brew out of fear.
Still, while a moderate amount of coffee may fit safely into daily life for many people with AF, it’s always a good idea to talk with a health care professional before making changes to your routine.
