Energy drinks deliver deadly jolt
Young people turning to heavily-caffeinated energy drinks to fuel themselves for partying, sport or just to get through the day are putting themselves at heightened risk of heart attacks and chronic heart problems.
In a finding that suggests the marketing and consumption of so-called energy drinks should be much more tightly regulated, a detailed American study of their use has found they are associated with “adverse cardiovascular events”, including sudden and deadly heart attacks, ruptured arteries, heart arrhythmia, tachycardia and elevated blood pressure, particularly among adolescents and young adults.
“By unleashing the new ‘beast’ of energy drinks, we have now seen significant morbidity and mortality in susceptible patients,” the study’s authors said. “Young consumers are at a particularly high risk of complications due to hazardous consumption patterns, including frequent and heavy use.”
The study, Cardiovascular complications of energy drinks, published in the latest edition of the journal Beverages, documented numerous cases where people died or suffered serious cardiovascular problems after consuming energy drinks.
These include a 28-year-old man who collapsed while playing basketball after drinking three cans of energy drink five hours before the match. He was rushed to hospital suffering ventricular tachycardia and died three days later.
In another case, a 25-year-old woman with a pre-existing heart valve problem died from intractable ventricular fibrillation after drinking a 55 millilitre bottle of Race 2005 Energy Blast with Guarana and Ginseng. Subsequent tests found the drink contained caffeine at a concentration of 10 grams a litre – more than 60 times that in cola drinks – and the caffeine in the woman’s bloodstream was concentrated at 19 milligrams a litre, around double the level found in regular coffee drinkers.
The drinks have also been associated with potentially fatal spasms of coronary arteries. One case involved a man, 28, who drank between seven and eight cans of energy drink over a seven-hour period before and during motocross racing. Soon after he stopped he suffered a cardiac arrest, and was found to have had a coronary artery vasospasm doctors believe was precipitated by high levels of caffeine and taurine in his blood.
In addition to heart attacks and arterial spasms, energy drinks have also been associated with surges in blood pressure that can lead to rupture of arteries, and with the impairment blood vessel linings.
The authors said that while some of the cases involved people with pre-existing and underlying cardiac condition, many others did not. They reported the results of a review of 17 cases where people suffered heart attacks or other cardiac “events” after consuming energy drinks and found almost 90 per cent were younger than 30 years of age, and the majority did not have a cardiac abnormality.
While energy drinks advertise high concentrations of caffeine – around 80 milligrams in cans of Red Bull, Monster and Rockstar, and more than 200 milligrams in a 60 millilitre can of 5-Hour Energy compared with around 35 milligrams in a can of cola – researchers said other common ingredients, particularly taurine, which can interfere with the regulation of the cardiovascular system, could also have potentially severe consequences.
The researchers admitted that “confounding variables”, such as strenuous exercise, genetic predispositions and the simultaneous use of alcohol or recreational drugs meant that many deaths could not be attributed to energy drinks alone.
But they said it was clear that consuming energy drinks was associated with “cardiovascular events including death”, and urged much greater attention be paid to their use.
The US Food and Drug Administration reported 18 deaths associated with energy drinks between 2004 and 2012, and the researchers said that because the FDA reporting system typically captured between 1 and 10 per cent of actual adverse events, it was likely there were at least 180 deaths associated with energy drinks during that period.
Given the widespread consumption of energy drinks – Australia’s Food Regulation Standing Committee found that sales of energy drinks in Australia and New Zealand jumped from 34.5 million litres in 2001 to 155.6 million litres in 2010 – the study’s authors have called for greater awareness of the danger they present, particularly for young people, who are typically the biggest consumers.
“Children, young adults and their parents should be aware of the potential hazards of energy drinks,” the authors said. “Physicians should routinely inquire about energy drink consumption in relevant cases, and vulnerable consumers such as young persons should be advised against heavy consumption, especially with concomitant alcohol or drug ingestion.”
The researchers said there was no rigorous scientific evidence that energy drinks boosted energy or improved physical or cognitive performance, and there needed to be public education campaigns to highlight the hazards and dispel the myths about their benefits.
They called for eventual limits on the caffeine content of energy drinks and restrictions on their sale to young people, echoing calls from the AMA and the Country Women’s Association.
The AMA has for several years raised concerns about the health effects of energy drinks and their heavy consumption among young people, including children.
In 2013, the-then AMA President Dr Steve Hambleton demanded that the caffeine content of energy drinks be reduced, or their sale restricted to adults, following evidence linking them to serious effects in young people, including tachycardia and agitation.
In 2009, the death of a young woman was linked to caffeine from energy drinks, and a study published in the Medical Journal of Australia found 297 calls relating to caffeinated energy drinks were made to the NSW Poisons Information Centre between 2004 and 2010, 128 of which resulted in hospitalisation.
Two years ago the Country Women’s Association of New South Wales submitted a petition with 13,600 signatures to Federal Parliament calling for a ban on energy drink sales to everyone younger than 18 years.
Both the AMA and the CWA have highlighted inconsistencies in food standards that limit the amount of caffeine in soft drinks to a maximum of 145 milligrams per kilogram, but impose no similar limit on energy drinks.
Image by Au Kirk on Flickr, used under Creative Commons licence