Research presented at the American Heart Association's Scientific Sessions 2026 in Chicago links caffeinated energy drinks and stimulant supplements to far more reports of serious heart events than other consumables.

NBC News reports the findings suggest these products may put young adults at greater risk for heart problems, including cardiac arrest. The University of Virginia study team analyzed a government safety database covering reports from people ages 13 and older between 2017 and 2025.

The industry stakes are large: sales of caffeinated energy drinks have more than doubled over the past decade, reaching over $20 billion in 2024, according to the AHA newsroom.

The surprise is who shows up in the data. Adults ages 18 to 34 are not usually considered at high risk for cardiovascular events, yet the AHA release states about 45% of reports tying caffeine- and stimulant-containing products to cardiovascular events involved that age group.

NBC News notes clinicians have described cases of arrhythmias or sudden cardiac death in people who consumed these products, many of them young adults with no known heart disease risks.

Study author Sai Samayamanthula says these products are marketed as everyday pick-me-ups sold next to soda and bottled water, so most people assume they carry no real risk.

Researchers analyzed 28,345 adverse-event reports to the FDA from 2017 to 2025, comparing 854 reports mentioning caffeine or stimulant products with 27,491 about products without them.

Per the AHA release, cardiac arrest was reported about 11 times more often with caffeine- and stimulant-containing products; those reports were about 4.5 times more likely to include heart attacks and four times more likely to include ventricular arrhythmias or palpitations.

Elevated heart rate appeared nearly 3 times more often, chest pain 2.71 times, and fainting about 2 times, with similar patterns for men and women.

The study is an abstract, not peer-reviewed, and its findings are considered preliminary until published in a full manuscript. According to the AHA, the analysis only identified associations from voluntarily self-reported FDA data and cannot prove these products caused any events.

Cardiologist Gregory M. Marcus, who was not involved, said the study does not prove caffeine products cause these events because other factors may have influenced the results.

The AHA's 2026 scientific statement says up to 400 mg of caffeine daily is generally safe for most adults, but some energy drinks carry up to 3 times more caffeine per fluid ounce than brewed coffee, and some pre-workout supplements more than 12 times.

Researchers say the findings support the case for more systematic safety monitoring of caffeine- and stimulant-containing products, and Samayamanthula urges healthcare professionals to ask younger patients with palpitations, chest pain, or fainting spells whether they recently or regularly consume these products.

The AHA notes the FDA regulates energy drinks and stimulant supplements as foods or dietary supplements rather than medications, so they skip the premarket safety testing required for drugs. More studies are needed to understand the relationship, the researchers said.