Energy Drink Effects on Hemodynamics and Endothelial Function in Young Adults

Cardiovascular side effects associated with energy drink consumption may be related to effects on vascular endothelial function, heart rate, blood pressure, and electrocardiogram parameters. We sought to measure them following energy drink consumption.

Forty-four healthy non-smoking young volunteer medical students, at an average age of 24.7 years (range 23-27 years, 34 males), with an average BMI of 23.4, received electrocardiograms and had their heart rates and blood pressures taken. Subjects then underwent baseline testing of endothelial function using the technique of endothelium-dependent flow-mediated dilatation (FMD) with high-resolution ultrasound. The subjects then drank an energy drink (24 oz Monster Energy Drink®). Hemodynamic measurements were repeated 15 and 90 min later. FMD and the electrocardiogram were repeated 90 min later. The FMD was calculated as the ratio of the post-cuff release and the baseline diameter.

Energy drink consumption resulted in a significantly attenuated peak FMD response (mean ± SD): baseline 5.1 ± 4.1% versus post-energy drink (2.8 ± 3.8%; p = 0.004). In addition, systolic and diastolic blood pressures and heart rate increased after 15 min. Diastolic blood pressure and heart rate remained increased 90 min following energy drink consumption. There were no significant changes in electrocardiogram parameters.

Energy drink consumption was associated with an acute significant impairment in endothelial function in young healthy adults as well as with significant hemodynamic changes. As energy drinks are becoming more popular, it is important to study their effects to better determine safe consumption patterns.