Study Finds Link Between Energy Drinks, Increased Heart Contractions

CHICAGOEnergy drinks loaded with caffeine and taurine could make the heart work harder, according to a study presented Monday at the annual meeting of the Radiological Society of North America.

The study conducted by researchers at the University of Bonn in Germany could cast further suspicions on whether energy drinks pose health risks amid an increasing number of sensational reports linking the popular products to deaths and other serious ailments.

The participants who consumed the beverages15 men and 3 women with a mean age of 27.5 yearswere found to have "significantly increased" contractions in the left ventricle of their hearts, the researchers said. The drinks contained 32 mg per 100 ml of caffeine and 400 mg per 100 ml of taurine.

"Until now, we haven't known exactly what effect these energy drinks have on the function of the heart," said radiology resident Jonas Dorner, M.D., of the cardiovascular imaging section at the University of Bonn.

The researchers found no material differences in blood pressure, heart rate or the amount of blood ejected from the left ventricle between the volunteers' baseline magnetic resonance imaging and the second MRI exams.

"We've shown that energy drink consumption has a short-term impact on cardiac contractility," Dr. Dorner said. "Further studies are needed to evaluate the impact of long-term energy drink consumption and the effect of such drinks on individuals with heart disease."

Dr. Dorner acknowledged that long-term risks to the heart from consuming energy drinks is unknown. Still, he advised that children and consumers with cardiac arrhythmias avoid them because changes in contractions could trigger arrhythmias. He also said additional research is needed to examine the risks posed by the sometimes fatal combination of energy-drink and alcohol consumption.