Statement Highlights:
Embargoed until 4:00 a.m. CT / 5:00 a.m. ET Monday, July 20, 2026
DALLAS, July 20, 2026 — Previous studies have found that caffeine is the world’s most popular stimulant and psychoactive substance, and coffee is the most common way people consume caffeine. The latest research supports the conclusion that for most adults, consuming up to 400 mg of caffeine/day (or up to 5, 8-ounce cups of caffeinated coffee per day) is safe and appears to be linked to a lower risk of cardiovascular disease for some individuals. However, higher doses of caffeine, such as levels found in energy drinks including energy shots, may cause cardiovascular harm, according to a new American Heart Association scientific statement, “Caffeine and Cardiovascular Disease,” published today in the American Heart Association’s flagship peer-reviewed scientific journal Circulation .
“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,” said Chair of the scientific statement volunteer writing group Gregory M. Marcus, M.D., M.A.S., FAHA, a professor of medicine at the University of California, San Francisco School of Medicine and the associate chief of Cardiology for Research at the University of California, San Francisco Health. “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 authors note that studying the effects of caffeine on the cardiovascular system is challenging. Coffee is the main source of caffeine in most research studies, and the observed cardiovascular effects may be due to other compounds in coffee. For example, experimental studies suggest that the bioactive compounds in coffee may have antioxidant and anti-inflammatory properties, which may help explain some health benefits. It’s also difficult to separate the effects of caffeine from other ingredients usually added to coffee, such as milk, cream, flavored syrups and/or sugar. In addition, most studies on caffeine are observational, meaning they cannot prove cause and effect.
Although coffee is the main source of caffeine for most adults, tea, chocolate, soda and energy drinks, as well as over-the-counter and prescription medications, also contribute to overall caffeine intake. More research is needed about other products with caffeine in order to understand caffeine content and caffeine’s impact on cardiovascular health.
The new scientific statement details the most recent research primarily on caffeinated coffee and the potential impact of caffeine in coffee on high blood pressure, cholesterol , Type 2 diabetes , coronary heart disease , stroke , heart failure , atrial fibrillation , other arrhythmias and other cardiovascular conditions.
Caffeine and cardiovascular health: key things to know
How does caffeine affect the body?
Caffeine consumed in coffee is metabolized by the liver and generally reaches peak concentration for most people within an hour. However, how quickly individuals process caffeine depends on their genetics, metabolism, age and past caffeine use. When more caffeinated coffee is consumed regularly, some people may develop a tolerance to higher levels of caffeine. Other people may feel stronger effects from the same amount of caffeine. Short-term effects of caffeine may include temporary increases in blood pressure, heart rate, blood sugar and alertness. Some people may experience heart palpitations and/or sleep disruption.
Specific health impacts of caffeine:
Not all sources of caffeine are the same
More research is necessary to investigate the different health impacts of various types of caffeinated coffee and other products with caffeine, such as tea, soda, energy drinks and energy shots, and foods. There have been fewer studies focused on tea vs. coffee; however, tea has been associated with reduced risk of atrial fibrillation, heart failure and stroke, similar to caffeinated coffee. Energy drinks, bars, gels and caffeine-based supplements often contain other added ingredients that may increase the absorption of caffeine, may accelerate its effects on the body, may raise blood pressure and increase the risk of cardiovascular harm.
More randomized controlled trials investigating the effects of caffeine in coffee and other products that have caffeine on cardiovascular health are needed to better understand how caffeine affects different people and how different sources of caffeine impact heart health. The writing group emphasized that there is also a need for research focused on caffeinated energy drinks and other popular products containing caffeine. Due to the lack of sufficient, rigorous data to develop guidance on recommendations for caffeine intake, caffeine was not referenced in the Association’s 2026 Dietary Guidance to Improve Cardiovascular Health .
“Although research suggests that caffeine consumption may be associated with certain cardiovascular benefits for some people, it’s important to remember that there is no ‘one-size-fits-all’ strategy for safe caffeine consumption. People can respond very differently to caffeine based on various factors, such as age, medications, underlying health conditions, genetics and how quickly their bodies metabolize it. 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,” Marcus said.
This scientific statement was prepared by the volunteer writing group on behalf of the American Heart Association’s Council on Lifestyle and Cardiometabolic Health; the Council on Clinical Cardiology; and the Stroke Council. American Heart Association scientific statements promote greater awareness about cardiovascular diseases and stroke issues and help facilitate informed health care decisions. Scientific statements outline what is currently known about a topic and what areas need additional research. While scientific statements inform the development of guidelines, they do not make treatment recommendations. American Heart Association guidelines provide the Association’s official clinical practice recommendations.
Co-authors are Vice Chair Frank B. Hu, M.D., M.P.H., Ph.D., FAHA; Rob M. van Dam, Ph.D.; Marilyn C. Cornelis, Ph.D.; Thomas A. Dewland, M.D.; JungHee Kang, Ph.D., M.P.H., R.N.; Susanna C. Larsson, Ph.D.; Robert L. Page II, Pharm.D., M.S.P.H., FAHA; and Niyati Parekh, Ph.D., FAHA. Authors’ disclosures are listed in the manuscript.
The Association receives more than 85% of its revenue from sources other than corporations. These sources include contributions from individuals, foundations and estates, as well as investment earnings and revenue from the sale of our educational materials. Corporations (including pharmaceutical, device manufacturers and other companies) also make donations to the Association. The Association has strict policies to prevent any donations from influencing its science content and policy positions. Overall financial information is available here .
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About the American Heart Association
The American Heart Association is a relentless force for a world of longer, healthier lives. Dedicated to ensuring equitable health in all communities, the organization has been a leading source of health information for more than one hundred years. Supported by more than 35 million volunteers globally, we fund groundbreaking research, advocate for the public’s health, and provide critical resources to save and improve lives affected by cardiovascular disease and stroke. By driving breakthroughs and implementing proven solutions in science, policy, and care, we work tirelessly to advance health and transform lives every day. Connect with us on heart.org , Facebook , X or by calling 1-800-AHA-USA1.
Circulation
Caffeine and Cardiovascular Disease: A Scientific Statement From the American Heart Association