Good news for coffee lovers with atrial fibrillation (A-fib): a new study suggests that a daily cup of coffee may actually reduce the risk of irregular heart rhythms. Researchers found that participants with A-fib who drank one cup of coffee each day were 39% less likely to experience an A-fib episode compared to those who avoided caffeine altogether.

According to the American Heart Association, the findings — published in JAMA — challenge the long-held belief that coffee triggers or worsens atrial fibrillation. The six-month study, called the Does Eliminating Coffee Avoid Fibrillation (DECAF) trial, involved 200 adults with an average age of 69. All participants had been diagnosed with A-fib and had their heart rhythm restored to normal through medication or electrical shock before the study began.

Half of the participants continued drinking at least one cup of coffee per day, while the other half were instructed to avoid caffeine completely. Those already on A-fib medication continued taking their prescribed drugs throughout the study.

Key findings included:

─ Forty-seven percent of the coffee group experienced a recurrence of A-fib or atrial flutter — a rapid but regular heartbeat lasting more than 30 seconds — compared to 64% in the no-caffeine group. This represents a 39% lower risk for those who drank coffee daily.
─ Similar reductions were observed when researchers analyzed only A-fib episodes.
─ Overall, the study suggested that caffeinated coffee may not raise the risk of A-fib and might actually reduce it.

However, the researchers cautioned that participants were already coffee drinkers, so the results may not apply to people who start drinking caffeinated beverages or consume energy drinks.

“Our study results suggest that caffeinated coffee may not be responsible for raising the risk of A-Fib and may even reduce it,” said senior study author Dr. Gregory M. Marcus. “It is reasonable for healthcare professionals to let their A-Fib patients consider experimenting with naturally caffeinated substances that they may enjoy, such as caffeinated tea and coffee. However, some people may still find that caffeine or caffeinated coffee triggers or worsens their A-Fib.”

The American Heart Association notes that A-fib is the most common type of irregular heart rhythm and can lead to blood clots, stroke, heart failure, and other serious complications. Currently, about five million Americans are living with A-fib, and that number is expected to rise to more than 12 million by 2030.

While more research is needed to confirm the benefits of caffeine for heart rhythm disorders, this study offers hope that coffee — once thought to be a trigger — may actually be part of a heart-healthy lifestyle for some people with A-fib.