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Each year, Americans spend roughly $12.5 billion on energy drinks for a pre-workout boost or to beat a mid-afternoon slump — unaware they may get more than just a caffeine buzz.
Claire Squires, a fit and healthy 30 year-old, obtained a new workout drink powder before the 2013 London Marathon. The drink claimed to boost energy, concentration, and metabolism — three things Claire figured she would need to get through her race. Instead, it led to heart failure. Squires died only one mile from the finish line.
The drink linked to Squires’ death, Jack3D, was found to contain DMAA, an amphetamine derivative posing as a natural supplement. Though Jack3D is no longer available to consumers, multiple other drinks contain DMAA and/or additional dangerous ingredients, says Dr. Pieter Cohen of the Cambridge Health Alliance and Harvard Medical School.
“So little is known about these ingredients that we don’t know for certain what the effects are in humans,” says Cohen. “However, because of similar action to other stimulants and case reports in the medical literature, I am very concerned they may increase the risk of heart attacks and strokes in some people — even healthy, active individuals.”
Cohen’s concerns are valid. According to new research presented at the 2013 meeting of the Radiological Society of North America, healthy individuals who consume energy drinks can experience rapid heart contractions and increased strain on the heart. These can lead to serious or life-threatening injuries such as convulsions and a heart attack, and death.
Between 2009 and 2012, the FDA received 13 reports of deaths linked to 5-Hour Energy and five deaths mentioned in connection with Monster Energy. Multiple adverse events, including myocardial infarction, renal failure, and spontaneous abortion, were also cited in the FDA Adverse Event Reports on energy drinks.
Effects On Athletes
“Caffeine is the most common ingredient found in most energy drinks. Strong evidence has shown caffeine may increase endurance performance, time to exhaustion and alertness, while decreasing perceived exertion,” says Dr. Christine Karpinski, Director of Sports Dietetics — USA for the Sports, Cardiovascular and Wellness Nutrition (SCAN) dietetic practice group. “Unfortunately, many energy drinks contain other ingredients, such as stimulants, herbals, and amino acids that may pose a danger to athletes.”
Many energy drink manufacturers aren’t required by the Food and Drug Administration to disclose ingredient blends, possible interactions with other foods or medications, or potential side effects. In addition, manufacturers may not report the total amount of caffeine and stimulants in the product. This may lead to an intake of caffeine and stimulants exceeding the recommended dosage, leading to side effects that may derail training or racing efforts.
Despite claims made by manufacturers, ingredients such as taurine, yerba mate, or superdoses of vitamins have very little benefit for athletes. A 2012 study published in Nutrition Reviews revealed that the “energy” produced from the beverages stems almost exclusively from their caffeine content. In other words, athletes can gain the same benefit from a cup of coffee or a caffeinated gel, without the side effects linked with energy drinks.
A Safer Buzz
When used correctly, standalone caffeine sources can certainly be an ergogenic aid for athletes. Experts suggest using caffeine sparingly, to maximize its effectiveness when consumed during hard training and racing efforts. As for dosage, more is not necessarily better.
“When taking caffeine, the recommended dosage for the enhancement of sports performance while minimizing side effects is 3-6 milligrams per kilogram of body weight one hour before exercise,” Karpinski says.
Karpinski also cautions athletes to be careful when using any supplement designed to enhance athletic performance. “Remember that the supplement industry is not tightly regulated, so there is always a risk when taking a dietary supplement,” she says.
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