Drinking at least one cup of coffee a day may help prevent heart failure

• New research found drinking one to three cups of coffee a day was linked to better heart health.
• Any benefits seemed limited to caffeinated coffee; decaf was linked to a risk of heart failure.
• One researcher noted coffee's links to heart health weren't yet as clear as, say, those of exercise.

Science is once again supporting the health benefits of your daily coffee fix.

Drinking at least one cup of coffee a day could reduce your risk of heart failure, with more coffee linked to even lower risk, according to research published February 9 in Circulation: Heart Failure, a journal of the American Heart Association.

Researchers looked at data from three studies, including 21,000 adult participants over at least 10 years of follow up. Data from two of the studies indicated that each cup of caffeinated coffee that participants drank a day was linked to a 5% to 12% lower risk of heart failure, compared with participants who didn't drink coffee. That was true for up to three cups of coffee a day, the research found. The third study found a 30% lower risk of heart failure in those who drank at least two cups of coffee a day.

Decaf coffee wasn't linked to the same benefits, and one of the studies actually linked it to a higher risk of heart failure.

That suggests caffeine would be at least partially responsible for any heart-health benefits of coffee, according to Dr. David Kao, an assistant professor of cardiology at the University of Colorado School of Medicine who was a senior author of the study.

"The association between caffeine and heart failure risk reduction was surprising," Kao said in a press release. "Coffee and caffeine are often considered by the general population to be bad for the heart because people associate them with palpitations, high blood pressure, etc."

Read more: Coffee drinkers have stronger bones than people who don't sip a daily brew, according to a new study

The research isn't convincing enough yet to recommend that people who don't drink coffee should start, based on the health benefits, the researchers concluded. Particularly for heart health, the best advice is still to exercise, maintain a healthy weight, and avoid smoking, Kao said in the press release.

If you do drink coffee, black is best

It's not clear how much coffee might produce optimal health benefits - one limitation of this research is that it relied on self-reported data, with no clear definition of how much coffee people were consuming per cup. Researchers also didn't collect data on the coffee-brewing method; previous research has found methods like filter brewing may be healthier than stovetop or French-press preparations.

What we do know is that many of the apparent benefits of coffee are linked to drinking it plain. Coffee in the form of sugary blended drinks or rich lattes are often loaded with sugar and saturated fat. Those additives could increase the risk of heart disease, mitigating any benefits of the coffee.

"The bottom line: enjoy coffee in moderation as part of an overall heart-healthy dietary pattern that meets recommendations for fruits and vegetables, whole grains, low-fat or non-fat dairy products, and that also is low in sodium, saturated fat, and added sugars," Penny Kris-Etherton, a professor of nutrition at Pennsylvania State University who was not involved in the study, said in the press release.

Coffee is linked to health benefits like a longer life and better health as you age

This study adds to a growing body of evidence that regularly drinking coffee could improve heart health and stave off premature death. It could also help promote weight loss, prevent cognitive decline as we age, and provide some protection against other chronic illnesses like liver disease and several types of cancer.

In addition to the caffeine, coffee also contains beneficial plant compounds called polyphenols, which are linked to antioxidant and inflammation-reducing effects.

Previous studies have indicated that coffee is safe and drinking it doesn't seem to have any long-term side effects, especially if you drink less than five cups a day.