Energy drinks are often marketed as a healthy beverage that can improve a person’s energy, stamina, athletic performance, and/or concentration. On the other hand, experts are increasingly voicing concerns that the cocktails of ingredients in these drinks could have unintended health risks. A new study published in Journal of the American Heart Association appears to prove their point.
The study, conducted by study author Sachin Shah, a professor of pharmacy at the Thomas J. Long School of Pharmacy and Health Sciences at the University of the Pacific, found that consuming 32 ounces of energy drinks in under an hour increased the risk of electrical disturbances in the heart. These changes lasted for as long as four hours after the drinks were consumed. The small study included thirty-four healthy volunteers between the ages of 18 and 40.
Shah and his team randomly assigned the participants to drink 32 ounces of one of two commercially-available caffeinated energy drinks, or a placebo drink, on three separate days. Both energy beverages had 304 to 320 milligrams of caffeine per 32 fluid ounces. The placebo contained carbonated water, lime juice, and cherry flavoring. The drinks were consumed as one 16-ounce serving per 30 minutes within a 60-minute period.
Measuring the electrical activity in the subjects’ hearts with an electrocardiogram found that the QT interval, the length of time it takes the ventricles in the heart to prepare to beat again, was higher in the participants who drank the energy drinks compared to the placebo drinkers. QT intervals that are too short or too long can cause life-threatening heart arrhythmias.
The researchers also found that those who had the energy drinks saw their blood pressure increase and remain elevated for the four-hour interval. Increased blood pressure can damage the arteries and the heart, leading to heart failure, stroke, and aneurysms.
The results of the study appear to echo previous studies on the matter. A review published in Frontiers in Public Health in 2017 also showed that energy drink consumption was linked to increased blood pressure. A study released last fall by American Heart Association found that drinking just one energy drink narrowed blood vessels 90 minutes later.