Energy drinks affect heart function

Energy drinks have been proven to affect heart contraction, even in healthy people. Research from the University of Bonn has shown that the caffeinated beverages increase the heart’s contraction rates, leading researchers to suggest that children and people with cardiac arrhythmia should avoid these drinks.

“Until now, we haven’t known exactly what effect these energy drinks have on the function of the heart,” said Dr Jonas Dörner, a radiology resident at the University of Bonn in Germany. “There are concerns about the products’ potential adverse side effects on health function, especially in adolescents and young adults, but there is little or no regulation of energy drink sales.

“Usually energy drinks contain taurine and caffeine as their main pharmacological ingredients. The amount of caffeine is up to three times higher than in other caffeinated beverages like coffee or cola. There are many side effects known to be associated with a high intake of caffeine, including rapid heart rate, palpitations, rise in blood pressure and, in the most severe cases, seizures or sudden death.”

Dr Dörner and colleagues used cardiac magnetic resonance imaging (MRI) to measure the effect of energy drink consumption on heart function in 18 healthy volunteers. Compared to baseline images, results of the cardiac MRI performed one hour after consuming an energy drink showed significantly increased peak strain and peak systolic strain rates in the left ventricle of the heart.

“We don’t know exactly how or if this greater contractility of the heart impacts daily activities or athletic performance,” Dr Dörner said. “We need additional studies to understand this mechanism and to determine how long the effect of the energy drink lasts.

“We’ve shown that energy drink consumption has a short-term impact on cardiac contractility. 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 Dörner also cautioned that an additional study is needed to address risks posed by the consumption of energy drinks in combination with alcohol.

News of the research findings comes just days after the Australian Beverages Council issued a statement condemning a move by the Tamworth Liquor Accord to ban the sale of energy drinks as a mixer after 9 pm.

“While the industry supports measures to curb antisocial behaviour that often occurs, banning a non-alcoholic mixer that contains only 80 mg of caffeine in a standard 250 mL can - which is the same as a cup of instant coffee and comprises less than 1% of overall bar sales - is a step too far,” said the council’s CEO, Geoff Parker.

“Leading global authorities like the UK Government’s Committee on Toxicology (2012) concluded that the current balance of evidence does not support a harmful toxicological or behavioural interaction between caffeine and alcohol. This confirms similar findings from the European Commission’s Scientific Committee on Food (2003) and the European Food Safety Authority (2009).

“The science doesn’t support the accord’s energy drink ban,” Parker said. “Common sense points to the issue of consuming excessive amounts of alcohol - whether that be before people leave their home on a night out or in licensed venues - as being the cause of late-night violence in and around premises. It’s not the mixer that’s the problem.”

The University of Bonn study is ongoing.