Energy drinks speed heart contractions, MRIs show

Energy drinks led almost 21,000 people in the U.S. to the emergency room in 2013, according to a report from the Substance and Mental Health Services Administration. This influx of emergency room visits led a team of cardiac radiologists to seek a reason behind the problems caused by energy drinks. Consuming lots of caffeine can cause your heart to beat much faster and can cause palpitations, an increase in blood pressure, or even more severe consequences, such as seizures or death, according to Dr. Jonas Dörner, a member of the research team and resident at the University of Bonn in Germany. The researchers used an MRI scanner on study participants both before and after they had consumed an energy drink, finding that the heart was strained more after consuming the energy drink. Dr. Dörner says, "We don't know exactly how or if this greater contractility of the heart impacts daily activities or athletic performance. We need additional studies to understand this mechanism and to determine how long the effect of the energy drink lasts."

Los Angeles Times, 12/3/13