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Plot twist: Coffee isn’t actually ‘bad’ for your heart. It might help it, study shows

But don’t think your hazelnut latte is in the clear.
Coffee beans
An analysis of more than 386,000 self-reported coffee drinkers — part of a U.K. biomedical database — offered no evidence that suggests the beverage causes cardiac arrhythmia, or irregular heartbeat. (John Walker | @fresnobee.com)

Coffee has a bad rap when it comes to heart health. While it’s true some people experience unsettling jitters and fluttering pulses, studies show the drink actually offers some health benefits, including reduced risks of cancer, liver disease, diabetes and Parkinson’s disease.

Now, new research from the University of California, San Francisco continues to crush misconceptions.

An analysis of more than 386,000 self-reported coffee drinkers — part of a U.K. biomedical database — offered no evidence that suggests the beverage causes cardiac arrhythmia, or irregular heartbeat. In fact, the study found that each additional cup of coffee consumed was associated with a 3% lower risk of the condition occurring.

The not-so-lucky people who react negatively to a cup of coffee likely carry some genes that cause them to metabolize caffeine differently than those without them. But even among those with the genetic predisposition, the researchers didn’t find an increased risk of arrhythmia, according to the study published Monday in the journal JAMA Internal Medicine.

Coffee is the primary source of caffeine for most people, and it has a reputation for causing or exacerbating arrhythmias,” senior and corresponding author Dr. Gregory Marcus, a cardiology professor who specializes in the treatment of arrhythmias at UCSF, said in a statement. “Our population-based study provides reassurance that common prohibitions against caffeine to reduce arrhythmia risk are likely unwarranted.”

The researchers note that the self-reported nature of their study, as well as the lack of details on the type of coffee and method of preparation, limits their ability to conclude a cause and effect relationship between coffee and poor heart health. However, their findings are in line with others on the topic.

“Only a randomized clinical trial can definitively demonstrate clear effects of coffee or caffeine consumption,” Marcus said. “But our study found no evidence that consuming caffeinated beverages increased the risk of arrhythmia.”

He said “coffee’s antioxidant and anti-inflammatory properties may play a role, and some properties of caffeine could be protective against some arrhythmias.”

But that still doesn’t mean you should start chugging coffee to decrease your risks of poor health outcomes. Instead, experts say to stick with the basics: stop smoking, maintain a healthy weight and exercise.

It’s obvious coffee can ring in a boost of energy and sharpen focus — at least for most people, the American Heart Association says. It can also improve your mood and performance during exercise. Growing evidence also shows coffee intake is associated with a reduced risk of Type 2 diabetes, Parkinson’s disease and Alzheimer’s disease.

Coffee contains antioxidants, too, which can prevent cell damage.

But the drink offers these health benefits only when consumed in moderation — and without all that cream, flavorings and sugar.

“We know that sugar has adverse effects,” Penn State University nutrition professor Penny Kris-Etherton told the AHA. “Even if you add sugar and don’t exceed your calorie needs, you’re still negating some of the benefits because sugar is a negative food ingredient.”

Federal diet guidelines say 400 milligrams, or about four cups, of caffeine per day is not “generally associated with dangerous, negative effects” among healthy adults, but “they’re not talking about these large frappuccinos that have at least 800 calories a beverage,” Kris-Etherton said.

“Very quickly, calories can add up, and weight gain will create negative effects on cardiac risk.”