12/10/2025
A cup of day keeps the a-fib away
200 patients with persistent atrial fibrillation, scheduled for cardioversion, who consumed at least 1 cup of coffee per day for some time period in the past 5 years, were enrolled & compared to peers who either fully abstain from caffeine or stopped after their physician told them it would make their A-Fib worse. Patients all wore Apple watches with active ECG sweeping in addition to remote ECG monitors to track progress of A-Fib. All patients had a successful cardioversion & were monitored for reappearance of A-Fib.
Results? Contrary to popular belief, caffeine consuming patients had a 39% reduced risk for future A-Fib recurrence.
Awesome discussion from the study authors in comments on the pharmacokinetics of caffeine mediating normal sinus rhythm instead of making it worse: caffeinated coffee reduces blood pressure (diuretic effects), reduces inflammation (flavanol chemicals in coffee are anti-inflammatory in nature), and people juiced up on caffeine take more steps per day than peers.
IMPORTANT to note - consumption in the study was one cup per day! So this doesn't give you free reign to overindulge.