It may speed you up in the morning, but drinking coffee, tea or chocolate does not appear to cause heart palpitations, heart fluttering and other out-of-sync heartbeat patterns, researchers say.
Their report challenges a widely held belief that caffeinated drinks may cause irregular heart rhythms that can lead to heart failure or dangerous heart rhythm disorders. And it's another reason to enjoy that morning cup without guilt.
It might be time for doctors to lighten up on coffee, says Dr. Gregory Marcus, a cardiologist at the University of California San Francisco, who led the study.
"We may unnecessarily be discouraging consumption of items like chocolate, coffee and tea that might actually have cardiovascular benefits," Marcus said in a statement.
Doctors used to believe that premature cardiac contractions, which usually cause no symptoms or mild symptoms, such as heart palpitations, ‘skipped’ beats or fluttering, were harmless. But studies now show they’re associated with heart failure, atrial fibrillation and other dangerous conditions.
And doctors are widely taught that caffeine can cause these heart disturbances.
To check, Marcus and colleagues examined 1,388 people, with an average age of 72, taking part in a larger heart study.
About 60 percent said they drank some sort of caffeinated product every day. The team looked specifically at coffee, tea and chocolate and did not ask about super-caffeinated energy drinks.
They measured instances of premature ventricular contractions and premature atrial contractions.
They could not find any differences in instances of these heart disturbances, no matter how much coffee or tea or chocolate people had.
“Therefore, we are only able to conclude that in general, consuming caffeinated products every day is not associated with having increased ... arrhythmia but cannot specify a particular amount per day,” Marcus and colleagues wrote in the Journal of the American Heart Association.
"Habitual coffee drinkers have lower rates of coronary artery disease."
They said it is possible that people who noticed heart flutters or other symptoms from coffee or tea may have cut back — they did not ask them.
But they also noted that it’s another finding in favor of moderate coffee drinking.
“Coffee is among the most commonly consumed beverages in the United States and is the main source of caffeine intake among adults,” they wrote.
“Regular coffee consumption has been associated with a lower risk of Type 2 diabetes mellitus and other cardiovascular risk factors such as obesity and depression,” they added.
“Furthermore, large observational studies have found that habitual coffee drinkers have lower rates of coronary artery disease and of cardiovascular and all-cause mortality.”
The cutoff seems to be around five cups a day, and kids shouldn't be drinking too much caffeine.
Higher doses of caffeine can be deadly. The Food and Drug Administration has warned about sales of powdered caffeine, One teaspoon delivers as much caffeine as 28 cups of regular coffee.