Coffee won’t make the heart quiver: study

A study just published in JAMA Internal Medicine analyzed coffee consumption by more than 386,000 people over a three-year period and compared that with rates of cardiac arrhythmia, which might include atrial fibrillation.

After adjusting for demographics, lifestyle habits and diseases and conditions that might cause heart flutters, "each additional cup of habitual coffee consumed was associated with a 3% lower risk of incident arrhythmia," wrote corresponding author and arrhythmia specialist Dr. Gregory Marcus, a professor in the division of cardiology at the University of California San Francisco, in the study.

The new study suggests coffee drinkers can put aside fears that daily consumption will cause heart palpitations, or cardiac arrhythmia, as it’s known in the medical community.

What about coffee jitters? The CYP1A2 gene, known as "coffee gene," helps to metabolize caffeine. People with a fully functioning gene, which can be affected by lifestyle habits such as smoking, metabolize coffee at a normal rate. That suggests they can drink coffee without ill effect.

“A general ban on caffeine to reduce the risk of arrhythmias is probably unjustified,” a researcher said.