The American Heart Association released a new scientific statement today clarifying the cardiovascular effects of caffeine, concluding that moderate coffee consumption—up to five 8-ounce cups daily—is safe for most adults and may reduce the risk of heart disease, stroke, heart failure, and Type 2 diabetes. However, the statement warns that high doses of caffeine, particularly from energy drinks and energy shots, can increase the risk of high blood pressure and irregular heart rhythms.
Published in the journal Circulation, the statement reviews the latest research on caffeine and cardiovascular health. According to Gregory M. Marcus, M.D., M.A.S., FAHA, chair of the writing group and professor of medicine at the University of California, San Francisco, “Caffeine consumed in coffee is a key part of daily life for millions of people, and in our review of the most recent research, for most adults, intake of up to 400 mg of caffeine/day, the equivalent of up to 5 cups of caffeinated coffee per day without added sugars or fillers, is safe and does not increase cardiovascular risk.” He added, “However, high doses of caffeine, such as those found in energy drinks including energy shots, may have harmful effects on the heart and should be avoided.”
The statement highlights that moderate coffee consumption (1-3 cups per day) was not associated with an increased risk of atrial fibrillation, but was linked to more premature ventricular contractions. Drinking 2-4 cups daily was associated with lower risks of heart disease, heart failure, and stroke, though consuming more than 4 cups may increase heart failure risk. For blood pressure, 1-3 cups daily was linked to a higher risk of developing high blood pressure, while more than 3 cups was associated with a lower risk. High doses of caffeine from energy drinks significantly raised blood pressure, especially in those with existing hypertension.
Importantly, the benefits appear tied to black coffee without additives. Adding sugar, cream, or flavored syrups likely reduces health benefits. The statement also notes that unfiltered coffee (e.g., espresso, French press) contains cafestol, which can raise LDL cholesterol, while filtered coffee does not. The writing group emphasized the need for more research on other caffeine sources, as energy drinks often contain additional ingredients that accelerate caffeine absorption and may increase cardiovascular harm.
Marcus stressed that individual responses to caffeine vary based on genetics, metabolism, age, and medications. “There is no ‘one-size-fits-all’ strategy for safe caffeine consumption,” he said. “What may be a reasonable amount for one person could cause unwanted effects, such as heart palpitations, anxiety or sleep disruption, in another. That’s why it’s important to pay attention to how your body responds to caffeine and talk with your healthcare team about what is right for you.”
The full statement is available online. For more on the Association’s dietary guidance, see the 2026 Dietary Guidance to Improve Cardiovascular Health.
