A new study has shown that a cup of coffee a day can actually protect the heart against atrial fibrillation — the most common cardiac arrhythmia, which can lead to stroke and heart failure.
Coffee is associated with a faster heart rate, so people with atrial fibrillation (AF) are often advised to avoid it.
Now, a new study, in The Journal of the American Medical Associationsuggests that this recommendation may need to be rethought.
Researchers from the University of Adelaide and the University of California, San Francisco (UCSF) led a clinical trial of 200 adults from Australia, the US and Canada with AF to test the impact of coffee on this heart rhythm disturbance.
For six months, 100 participants consumed at least one cup of coffee or one espresso per day, while the other 100 abstained from all types of coffee and caffeine. They were constantly monitored and all AF episodes were confirmed by doctors using electrocardiograms.
In the DECAF trial (Does Eliminating Coffee Avoid Fibrillation), researchers discovered that the caffeine resulted in a 39% lower risk of recurrence of AF episodes compared to those who abstained.
“The results were extraordinary. Contrary to conventional wisdom, we found that coffee drinkers experienced a significant reduction in AF compared to those who avoided coffee and caffeine,” said Professor Christopher X. Wonglead author of the study, from the University of Adelaide and the Royal Adelaide Hospital.
“This is surprising as it goes against the common assumption that coffee worsens heart rhythm disorders like AF,” he added.
Theories about coffee
Still unsure, scientists have some theories about the possible reasons why, in this study, caffeine reduced the risk of AF.
“Coffee increases physical activity, which is known to reduce AF”said the teacher Gregory Marcussenior author of the study and member of the UCSF Division of Cardiology, cited by New Atlas.
“Caffeine is also a diureticwhich can reduce blood pressure and, consequently, reduce the risk of AF. In addition, several other components of coffee have anti-inflammatory properties which can have beneficial effects”, he added.
