Having a daily cup of coffee or two may actually be good for heart, according to latest research.
Pooling the results from five studies of coffee consumption and heart failure risk, published between 2001 and 2011, researchers led by Dr. Murray Mittleman at Beth Israel Deaconess Medical Center in Boston report in the journal Circulation: Heart Failure that regular coffee drinkers had a lower risk of heart failure than those who abstained.
The key was moderation. Among the 140,220 participants included in the analysis, those who drank four to five European servings of coffee a day (equivalent to about two cups of coffee at popular American chains) had an 11% lower risk of heart failure during the study period, compared with those who didn’t drink coffee. Those drinking less coffee showed only a 4% reduction in risk, while those drinking more showed similarly slight reductions until they reached nine to 10 cups a day, at which point chances of heart failure started to increase.
Translated into U.S. coffee consumption, the results suggest that two 8-oz. cups of coffee a day would be associated with an 11% drop in heart risk, with increased risk linked to five cups or more.
The findings indicate that current heart failure prevention guidelines, which suggest that coffee may be harmful to the heart, might need revisiting, the study authors note. “While there is a commonly held belief that regular coffee consumption may be dangerous to heart health, our research suggests that the opposite may be true,” Mittleman said in a statement.
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“The results are reassuring, because a lot of people with heart failure or hypertension are discouraged from drinking coffee at all,” says Dr. Elizabeth Ross, spokesperson for the American Heart Association (AHA), who was not involved in the study. The AHA currently recommends coffee in moderation — one to two cups a day — for heart patients.
The results add to the growing number of studies on coffee’s potential health benefits. Previous research shows that coffee drinkers have lower risks of diabetes, cancer and stroke. Data suggest, for example, that people sipping more than six to seven cups of coffee a day are 35% less likely to have Type 2 diabetes than those drinking two cups or less a day. And because Type 2 diabetes increases the risk of heart disease, coffee drinkers may also enjoy fewer heart problems — as the current study also shows. In a study in 2009 looking at 83,000 women, those drinking one to two cups of coffee daily had a 20% lower risk of stroke than those who drank less. Other research shows that coffee drinkers are up to 65% less likely to develop neurological disorders such as Parkinson’s disease or Alzheimer’s.
But that still doesn’t mean people should start downing coffee in the hopes of staving off chronic disease. For one thing, says Ross, the current review did not analyze how the coffee was brewed — filtering coffee grounds can have an effect on the nutrients transferred from the bean to the cup. The study also did not distinguish between caffeinated and decaffeinated coffee, although most Europeans drink caffeinated coffee.
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The findings are enough to start questioning whether the advice against coffee consumption for heart failure patients needs to be revised. “There are many factors that play into a person’s risk of heart failure, but moderate coffee consumption doesn’t appear to be one of them,” Elizabeth Mostofsky, a co-author of the paper and a research fellow at Beth Israel Deaconess Medical Center, said in a statement.
Alice Park is a writer at TIME. Find her on Twitter at @aliceparkny. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.