An ongoing study presented at the Radiological Society of North America’s (RSNA’s) 99th Annual Scientific Assembly and Annual Meeting has reportedly claimed that energy drinks “significantly increased” heart contraction rates in healthy adults one hour after consumption. According to a December 2, 2013, RSNA press release, researchers with the University of Bonn, Germany, used cardiac magnetic resonance imaging (MRI) “to measure the effect of energy drink consumption in 18 healthy volunteers,” who apparently underwent cardiac MRI before and after consuming an energy drink containing 400 mg  of taurine and 32 mg of caffeine. The results evidently showed that, compared to the baseline images, the MRI taken one hour after energy drink consump- tion “revealed significantly increased peak strain and peak systolic strain rates (measurements for contractility) in the left ventricle of the heart.

”“Until now, we haven’t known exactly what effect these energy drinks have on the function of the heart,” said one of the researchers. “There are concerns about the products’ potential adverse side effects on heart function, especially in adolescents and young adults, but there is little or no regulation of energy drink sales… We need additional studies to understand this mechanism and  to determine how long the effect of the energy drink lasts.”

Meanwhile, Monster Beverage Corp. has issued a December 2 statement describing the study in question as “alarmist and misleading.” In particular, the company notes, scientists have long known that taurine “helps the heart function more efficiently by improving the pumping force of the heart without any changes in blood pressure or heart rate.”

“This effect of taurine, called contractility, is widely considered to be beneficial,” concludes the statement. “The author’s study does not document a negative effect on heart function. Although he concludes that the consumption of energy drinks should be restricted based on his study, this conclusion is unsupported by his data and highly misleading. No evidence exists that increased contractility causes arrhythmia.”