Drinking Coffee May Help Improve Heart Health, Lower Diabetes Risk

• A 2025 study found that coffee drinkers may have a 40% lower risk of AFib recurrence.
• More research from 2025 shows that drinking black coffee daily can lower a person’s overall mortality risk and their risk of death from cardiovascular disease.
• Another study from 2025 found that the polyphenols in black coffee may lower the risk of type 2 diabetes.

Many people enjoy starting their day with a cup (or two) of coffee. Approximately 66% of adults in the United States drink coffee on a daily basis.

Recent research has shown that coffee may be better for your heart than originally thought. Studies have also found that daily coffee consumption may also help reduce your risk of type 2 diabetes.

There are various potential health benefits associated with drinking coffee, including boosting energy, aiding in weight management, and potentially reducing the risk of depression.

However, it is essential to note that these benefits may diminish if you add significant amounts of sugar and saturated fats, such as cream, to your coffee. Experts recommend reducing your caffeine intake if you are pregnant or nursing.

Conventional medical wisdom has generally advised people who have atrial fibrillation (AFib) or who are at risk of it to cut back or avoid coffee.

However, the idea that coffee can lead to an increased risk of AFib has been scrutinized in recent years.

A recent clinical trial further challenged this idea. It suggested that instead of potentially triggering AFib, coffee may actually reduce the frequency. The trial results were published in JAMA near the end of 2025.

The randomized controlled trial, called DECAF, found that among 200 adults diagnosed with AFib or a related condition, atrial flutter, and with a history of AFib, those who drank coffee daily had fewer recurrent episodes than those who avoided caffeine entirely over a 6-month period.

“There have been conflicting thoughts about whether coffee affects atrial fibrillation,” Gregory Marcus, MD, a cardiologist and professor of medicine at the University of California, San Francisco, and senior author of the research, told Healthline.

“To our knowledge, this is the only long-term randomized trial of caffeinated coffee on any cardiovascular endpoint. It suggests that caffeinated coffee may protect against atrial fibrillation, at least among people that otherwise enjoy and tolerate caffeinated coffee,” he added.

At the end of the trial, the researchers saw a 40% lower risk of AFib recurrence among the individuals who regularly consumed coffee. The exact reasoning behind this reduction is still unclear.

The authors suggest that blocking adenosine may confer antiarrhythmic properties to caffeine. Adenosine is a naturally occurring chemical in the body that makes you feel drowsy. It’s part of how the body regulates energy and sleep cycles, but it’s also known to trigger AFib.

Another suggestion relates to the anti-inflammatory properties in coffee that may protect against AFib.

“Coffee, as we know, naturally contains antioxidant properties, such as chlorogenic acids and melanoidins, which may act as protective effects for our body and our heart,” said Alyssa Kwan, a clinical dietitian in Cardiology at Stanford Medicine who wasn’t affiliated with the research.

However, the study did not provide direct evidence for this or any other reasoning behind the AFib reduction.

The researchers reported that individuals who drank 1 to 3 cups of caffeinated black coffee per day with little to no sugar or saturated fats had a 14% lower overall mortality risk and a lower risk of death due to cardiovascular disease compared to those who drank no coffee.

However, they also noted that drinking more than 3 cups of coffee a day did not have an association with additional risk reduction. There was also no risk reduction for those who added significant amounts of sugar or fats to their coffee.

“It’s an interesting analysis in a nationally representative sample of U.S. adults that is largely consistent with existing studies finding the benefits of moderate coffee intake,” said Maya Vadiveloo, PhD, associate professor in the Department of Nutrition at the University of Rhode Island, chair of the American Heart Association (AHA) Nutrition Committee, and a registered dietitian, who wasn’t involved in the study.

Kristin Kirkpatrick, a registered dietitian and the president of KAK Consulting, as well as a dietitian at the Cleveland Clinic Department of Wellness & Preventive Medicine in Ohio, echoed these remarks. Kirkpatrick wasn’t involved in the study.

“The study is in line with previous studies showing mortality benefits to coffee consumption,” she told Healthline. “I also think that highlighting the fact that what we put in our coffee is often the culprit for a less healthy drink is a critical point for consumers.”

Still, the study may have some limitations. Zhaoping Li, MD, a professor of clinical medicine at the University of California, Los Angeles, said that the research utilized older databases, which were based on self-reported information by the participants. Li wasn’t involved in the study.

“You shouldn’t think that if you drink black coffee that it’s going to extend your life. That’s not what the study says,” said David Cutler, MD, a family medicine physician at Providence Saint John’s Health Center in Santa Monica, CA, who wasn’t involved in the study.

Cutler told Healthline that other factors may influence the results, such as the fact that people who drink coffee tend to be generally healthier than those who don’t.

A 2025 research analysis suggested that caffeinated or decaffeinated black coffee may help lower the risk of type 2 diabetes.

Researchers affiliated with universities in the Republic of Korea noted that individuals who drink 3 to 5 cups of black coffee daily may benefit from natural compounds called polyphenols.

The research showed that daily consumption of black coffee can have various benefits, including:

The results were similar for both caffeinated and decaffeinated coffee. This suggests that the benefits may derive from compounds other than caffeine. These benefits included a 20% to 30% decrease in the risk for type 2 diabetes in coffee drinkers.

Marilyn Tan, MD, a clinical associate professor of medicine at Stanford University in California, who was not involved in the study, had some cautions about the findings.

Tan told Healthline that the findings are notable, but added that some of the research reviewed was conducted in lab settings. She noted that observational studies often fail to account for external factors, such as the overall health of coffee drinkers.

The researchers of the analysis also note that further research is needed.

Zhaoping Li, MD, a professor of medicine and the chief of the Division of Clinical Nutrition at the University of California, Los Angeles, who was also not involved in the study, noted that people should be aware of their caffeine intake.

She said 3 cups daily is probably fine for most people, but some folks may not be able to handle the caffeine load from 4 or 5 servings per day.

People with certain heart conditions should also carefully monitor their caffeine intake. “Everybody is different,” Li said.