Preliminary research to be presented at the American Heart Association's Scientific Sessions found cardiac arrest was reported about 11 times more often with caffeinated energy drinks or stimulant supplements in FDA reports. The study shows associations only and is not yet peer-reviewed.
New research presented at the American Heart Association's annual meeting indicates energy drinks and stimulant-packed supplements may put young adults at greater risk for heart problems, including cardiac arrest. The preliminary work is to be presented at the association's Scientific Sessions 2026 in Chicago, Nov. 6 to 9. It found that cardiac arrest reports in a federal safety database were about 11 times more common when they involved caffeinated energy drinks or stimulant supplements than when they involved products without caffeine or stimulants.
How the analysis was done
Researchers from the University of Virginia School of Medicine reviewed 28,345 reports filed from 2017 to 2025 to an FDA safety database. Of those, 854 involved caffeinated energy drinks or stimulant dietary supplements, and 27,491 involved products without caffeine or stimulants. Sai Samayamanthula, a fourth-year medical student at the school, was among the researchers behind the independent analysis.
What the reports showed
Reports involving stimulant-containing products were about 11 times more likely to mention cardiac arrest and approximately 4.5 times more likely to mention heart attack than reports involving products without caffeine or other stimulants. They were also four times more likely to mention ventricular arrhythmias or heart palpitations, nearly three times more likely to mention elevated heart rate, 2.71 times more likely to mention chest pain, and about twice as likely to mention fainting. About 45% of reports describing heart-related events involved adults ages 18 to 34.
Caffeine content and regulation
According to the AHA release, some energy drinks contain up to three times as much caffeine per fluid ounce as brewed coffee, and some pre-workout supplements contain more than 12 times as much. Energy drinks and stimulant supplements are regulated as foods or dietary supplements, not medications.
Limits of the findings
The study identified associations rather than proving causation, relies on voluntary adverse event reports, and its findings are preliminary and not yet peer-reviewed. As a meeting abstract, it has not been published in a peer-reviewed journal, and the voluntary nature of the reports means it cannot show the products caused heart events. The researchers could not establish whether the products caused the reported conditions, and the figures reflect differences in adverse-event reporting, not the likelihood of a heart attack. Because the reports are voluntary, researchers do not know how many people consumed these products without problems. Gregory M. Marcus, who was not involved in the research, said the study does not prove that caffeine products cause these events and that more research is needed.
