A growing body of research is transforming how clinicians understand the relationship between coffee and atrial fibrillation, and new evidence is challenging long-held assumptions about caffeine and cardiac rhythm.
For decades, people with AFib were urged to avoid coffee because caffeine can stimulate the sympathetic nervous system and temporarily raise heart rate and blood pressure.
This advice seemed logical, yet it was based more on theory than on clinical evidence, and observational studies have increasingly questioned whether moderate coffee consumption actually increases arrhythmia risk.
Now, a new randomized clinical trial known as the DECAF study provides the strongest evidence to date that moderate coffee drinking may not only be safe for people with AFib but could reduce the risk of recurrence.
In this six-month trial of 200 adults with documented AFib, researchers found that individuals who continued drinking coffee daily experienced significantly fewer recurrent episodes than those who abstained entirely.
Participants who drank coffee had a 39 percent lower recurrence rate, a finding that stands in direct contrast to previous warnings and has prompted cardiologists to rethink long-standing recommendations.
The results were published in JAMA, and the study’s senior author emphasized that this is the first long-term randomized trial to examine the effects of caffeinated coffee on a cardiovascular endpoint.
The protective effect observed in the trial may be linked to caffeine’s ability to block adenosine receptors, which is notable because adenosine is known to provoke AFib.
Coffee may also offer anti-inflammatory and antioxidant benefits, with compounds such as chlorogenic acids potentially contributing to improved electrical stability in heart tissue.
These biological pathways echo findings from prior research on dietary antioxidants and cardiac function, including a discussion by cardiologist Dr. Sanjay Gupta in a publicly.
It is also possible that lifestyle factors play a supporting role.
A recent trial published in The New England Journal of Medicine, found that coffee drinkers took more daily steps and were more physically active, suggesting that routine movement may help lower AFib risk alongside moderate caffeine consumption.
These interconnected insights illustrate that coffee’s effects on the heart are more nuanced than once believed.
Moderate intake of naturally caffeinated coffee appears not to provoke AFib in people who already tolerate it well, and in some cases may even offer a mild protective advantage.
However, researchers caution that the findings apply specifically to coffee and not to other sources of caffeine, particularly energy drinks, which can contain much higher concentrations and have been linked to arrhythmia episodes in otherwise healthy individuals.
It is also essential to consider what is added to a cup of coffee, as beverages high in sugar or saturated fat may undermine potential benefits.
For individuals who rely on their morning cup as part of their daily routine, the emerging science suggests that moderate coffee drinking is unlikely to worsen AFib and may support rhythm stability.
Even so, clinical guidance remains individualized, and anyone advised by a clinician to restrict caffeine should consult their provider before making changes to their routine.
This evolving research reinforces that heart health recommendations must be grounded in evidence rather than assumptions, and the DECAF trial represents a meaningful step toward more personalized lifestyle guidance for people living with AFib.