Top Things to Know: Caffeine & Cardiovascular Disease
Updated: July 20, 2026
Prepared by Gregory M Marcus, MD, MAS, FAHA, Chair and Frank B Hu, MD, MPH, PhD, FAHA, Vice- Chair of the Writing Group
- Caffeine is rapidly absorbed and metabolized primarily by the liver enzyme CYP1A2, and by antagonizing adenosine receptors it increases sympathetic activity, leading to transient increases in blood pressure, heart rate, and alertness.
- Studies of caffeine, one of the most commonly consumed drugs in the world, are largely observational, meaning that confounding by other factors remains an important consideration in interpreting the majority of scientific results. Therefore, more randomized controlled trials investigating the effects of caffeine on cardiovascular health are needed.
- The majority of impactful studies investigating relationships between caffeine and cardiovascular health examine caffeine occurring in natural substances, mainly coffee. Therefore, it is often difficult to disentangle effects that may be related to caffeine itself versus other constituents of those commonly consumed substances.
- Individual responses to caffeine vary widely due to genetic differences in metabolism, as well as factors such as habitual intake, age, and comorbidities.
- Caffeinated coffee consumption is associated with a reduced risk of type 2 diabetes mellitus.
- Randomized controlled trial data suggest that caffeinated coffee reduces the risk of recurrent atrial fibrillation but may increase the frequency of premature ventricular contractions.
- High dose caffeine, such as in purified form, has been associated with malignant ventricular arrhythmias.
- Moderate caffeinated coffee consumption is associated with a lower risk of coronary artery disease and stroke.
- Low to moderate caffeinated coffee consumption is associated with a lower risk of heart failure, whereas excess coffee consumption (such as >4 drinks a day) may increase the risk for heart failure.
- Evidence derived from studies of caffeinated coffee consumed in normal amounts should not be extrapolated to caffeinated energy drinks. Case reports have generally suggested harm, primarily related to arrhythmias, of energy drink consumption, providing evidence that more research on this topic is needed.
Citation
Marcus GM, Hu FB, van Dam RM, Cornelis MC, Dewland TA, Kang J, Larsson SC, Page RL II, Parekh N; on behalf of the American Heart Association Council on Lifestyle and Cardiometabolic Health; Council on Clinical Cardiology; and Stroke Council. Caffeine and cardiovascular disease: a scientific statement from the American Heart Association. Circulation. Published online July 20, 2026. doi: 10.1161/CIR.0000000000001454