People often talk about caffeine as a potential risk factor for premature atrial and ventricular contractions (PACs and PVCs), types of heart arrhythmia that can cause palpitations or extra heartbeats. In common conversation, someone who just had a PAC or PVC may say they’ve felt their heart skip a beat. This isn’t quite the case—an extra beat comes early, causing a pause followed by stronger beat than usual. That stronger beat is the one you can perceive.
As a study published in Journal of the American Heart Association reported, though, there’s no scientific evidence to link PACs and PVCs to caffeine in the general population. Researchers looked for a connection between these extra beats and consumption of coffee, caffeinated tea, and chocolate, but found no difference in frequency of PACs and PVCs in participants who did or did not partake in these caffeinated items.
There have been rare cases, such as when a woman with pre-existing mitral valve prolapse died after consuming a guarana drink with the caffeine equivalent of 8 cups of coffee. As authors of a study on caffeine and arrhythmia point out, however, “such events are rare; most cardiac patients tolerate normal amounts of caffeine without difficulty.” The American Heart Association clarifies that almost everyone will experience these common PAC and PVC arrhythmias during their lives, usually without cause.
“As certain products may have cardiovascular benefits,” the authors write, “recommendations against them may be detrimental,” and heart health may not be the only benefit of consuming caffeine. For example, a study in the Journal of the American College of Cardiology notes that including coffee in one’s diet can lower the risk of type 2 diabetes, high blood pressure, obesity, gastrointestinal disease, asthma attacks, and even depression.
However, the results aren’t yet in as to whether caffeine has a connection to coronary heart disease. While scientists conducted various studies in an attempt to find out, results varied. The American Heart Association notes, “This may be due to the way the studies were done and confounding dietary factors.”
Regardless, consuming 1 or 2 cups of coffee a day hasn’t been linked to any ill effects. One study in 2015 even found that up to five cups a day had no relationship to heightened risk of death. Go ahead and enjoy your daily caffeinated treat, as long as it’s in moderation.