Scientists Find Caffeinated Coffee and Tea May Reduce Risk of Stroke, Heart Attack—Here’s How Much Impacts Health

Researchers followed up with participants after about 12 years and found that drinking two to three cups of coffee or up to three cups of tea a day was the sweet spot for cardiometabolic health. People who drank about 200 to 300 milligrams (mg) of caffeine a day had a lower risk of cardiometabolic disease, compared to those who drank less than 100 mg a day. Specifically, coffee drinkers had the lowest risk—nearly a 50% reduction in risk—while people who consumed 200 to 300 mg of caffeine from tea or a mix of both beverages were about 40% less likely to develop cardiometabolic disease. For exclusively tea drinkers, cardiometabolic risk decreased the most for those who drank up to three cups daily, but the benefits subsided for any additional cups a day.

What’s more, the study discovered that even for people who consumed more than 400 mg of caffeine a day—just 4% of the study’s caffeine drinkers—the stimulant didn’t appear to have negative consequences for their cardiometabolic health.

So, how can your morning jolt protect against type 2 diabetes, coronary heart disease, and stroke? Well, caffeinated coffee and tea contain compounds like antioxidants that help protect cells from damage, said Adedapo Iluyomade, M.D., preventative cardiologist with Baptist Health Miami Cardiac & Vascular Institute. “Both coffee and tea can improve how your body processes sugar, lower inflammation, and keep blood vessels healthy, which can prevent conditions like type 2 diabetes, heart disease, and stroke.” By reducing harmful effects on the body, moderate amounts of these drinks contribute to better overall health and reduce your risk of these diseases, he explained.

Whether you prefer coffee or tea, both beverages lower cardiometabolic risks, but they work differently, said Dr. Iluyomade. “Coffee tends to have a stronger impact on managing blood sugar, while tea, especially green tea, is better at improving blood vessel function and lowering blood pressure.” This is because they contain different types of antioxidants that have unique effects on the body. “Specifically, coffee contains higher levels of certain antioxidants, such as chlorogenic acids, while tea is rich in flavonoids, especially catechins,” Dr. Iluyomade said.

This study looked specifically at the caffeinated versions of these popular drinks. That said, decaf coffee and tea still contain many of the beneficial polyphenols and antioxidants found in their caffeinated counterparts, Dr. Iluyomade pointed out. “However, caffeine itself may help with boosting metabolism and improving how your body handles sugar,” he said. While decaf is a great option, especially for people sensitive to caffeine, caffeinated versions might offer a slight edge in terms of lowering the risk of conditions like diabetes and heart disease, he added.

You may be wondering if your other favorite caffeinated drinks provide potential benefits. Unfortunately, it’s not likely, said Dr. Iluyomade. While energy drinks contain caffeine, they often come with large amounts of sugar and artificial ingredients that may negatively affect heart health, he noted. “Unlike coffee and tea, which are rich in healthful compounds, energy drinks lack these natural benefits and can increase risks like high blood pressure. Therefore, it’s crucial to differentiate between natural sources of caffeine, like coffee and tea, and processed energy drinks,” Dr. Iluyomade explained.

The bottom line

This study adds to the growing evidence that moderate coffee or tea consumption, particularly when caffeinated, may reduce the risk of cardiometabolic diseases, said Dr. Iluyomade. “The findings highlight the potential for coffee and tea to play a role in disease prevention, specifically targeting major conditions like type 2 diabetes, coronary heart disease, and stroke,” he said. These results are important because they emphasize the value of dietary habits in managing and reducing cardiometabolic risk, particularly as the global burden of these diseases continues to rise, he pointed out.

The U.S. Food and Drug Administration (FDA) recommends that most adults consume no more than 400 mg of caffeine per day. This is roughly equivalent to two to three 12-ounce cups of coffee. However, people vary in sensitivity to caffeine and how quickly their bodies eliminate it. If you have conditions like high blood pressure or irregular heart rhythms, it’s worth discussing with your doctor how much caffeine is safe for you, said Dr. Iluyomade. “Also, make sure to look at your overall lifestyle—diet, exercise, and stress management are all crucial parts of keeping your heart and body healthy,” he added. These beverages can be a part of a heart-healthy lifestyle, but balance and moderation are key, he said.

And with that in mind, you should also consider how you sweeten your coffee or tea, said Melissa Mroz-Planells, D.C.N., R.D.N., national media spokesperson for the Academy of Nutrition and Dietetics and member of the Prevention Medical Review Board. “Adding too much cream and sugar can be contrary to lowering your risk.” Try a splash of a low-fat milk or dairy alternative and limit your sweeteners to one sugar, a teaspoon of honey, or a non-nutritive sweetener in your beverage, she recommended.