Caffeinated energy drinks and stimulant supplements were linked to a significantly higher number of reports of serious cardiovascular events, including cardiac arrest and heart attacks, in a review of Food and Drug Administration safety data spanning 2017 to 2025.
The findings, which are preliminary and have not yet been peer-reviewed, are scheduled for presentation at the American Heart Association’s Scientific Sessions 2026 in Chicago, taking place November 6–9.
Analysis of FDA Safety Reports
Researchers examined 28,345 adverse-event reports submitted to the FDA over the eight-year period. Of those, 854 reports specifically identified caffeinated energy drinks or stimulant-containing dietary supplements.
Energy drinks linked to heart attacks in young adults
The study found that reports of cardiac arrest were approximately 11 times more common among products containing caffeine or stimulants compared to those without them. Products in the stimulant category were 4.5 times more likely to be associated with heart attacks, and ventricular arrhythmias or palpitations were four times more likely. Other observed patterns included higher frequency reports of elevated heart rate and chest pain.
Because the data relies on voluntary reports to a federal safety database, the researchers noted that the analysis cannot definitively prove cause and effect. The reports do not indicate the total number of users, how many events went unreported, or specific consumption habits of the individuals involved. Dr. Gregory M. Marcus, who chaired the 2026 American Heart Association scientific statement on caffeine and cardiovascular disease and was not involved in this study, stated, More research is needed to understand whether these stimulant products are truly responsible for the reported heart-related events.
Impact on Young Adults
The data indicated that nearly 45 percent of the cardiovascular events reported in connection with these products involved adults aged 18 to 34. Researchers noted that this demographic is not typically considered at high risk for heart disease.
Researcher Highlights High Consumption Rates and Caffeine Limits
Study author Sai Samayamanthula, a fourth-year medical student at the University of Virginia School of Medicine, suggested that the high volume of reports among this age group may be tied to how frequently they consume these products, whether they mix them with alcohol or drugs, or if they have undiagnosed heart conditions. He noted that while occasional consumption may pose a small risk for many healthy people, regular use can lead to exceeding the recommended daily caffeine limit.
Some energy drinks contain up to three times as much caffeine per fluid ounce as brewed coffee, while certain pre-workout supplements may contain more than 12 times as much.
Council Challenges Study Methodology over Adverse Events
The Council for Responsible Nutrition (CRN) has challenged the methodology of the analysis, stating that the findings do not account for variables such as specific ingredients, consumption frequency, or adherence to label directions. Andrea Wong, Ph.D., CRN’s chief science officer, emphasized that adverse event reporting patterns cannot establish the incidence of cardiovascular events without information about how many people consumed the products.
Trade Group Notes Banned Ingredients and Recommends Monitoring Intake
The CRN also highlighted that the study included ingredients like ephedra, DMAA, and higenamine, which it noted cannot legally be marketed in food or dietary supplements under federal requirements. The organization maintained that moderate caffeine consumption is generally considered safe for most healthy adults. It urged consumers to monitor their total intake and consult healthcare professionals regarding concerns.
The American Heart Association recommends a daily caffeine limit of 400 mg.
For those concerned about the cardiovascular impact of these beverages, experts suggest consulting with a qualified healthcare professional to assess individual risks, particularly if one has underlying cardiovascular conditions or experiences symptoms like palpitations, chest pain, or lightheadedness.