While names like AMP Energy, Pepsi Max, Red Bull and Rockstar can sound exciting, that hyped-up feeling isn't from just the name -- one energy drink can pack as much caffeine as downing 15 cans of Coca-Cola, researchers say.
Researchers looked at energy drink ingredients, including caffeine, guarana, ginseng, taurine and sugars, and concluded that better performance can be attributed to the energy drinks' caffeine content. Two studies looked at energy drinks and their use by teenagers and athletes and have been published in the medical journal The Physician and Sportsmedicine.
With 100 brands of energy drinks being marketed for their abilities to increase alertness and improve performance, it's no wonder energy drink sales have increased 240% between 2004 and 2009, the researchers say.
Researchers from Michigan State University point out that most energy drinks have between 80 to 500 milligrams of caffeine per bottle or can -- almost 15 times the 34 mg found in a 12-ounce can of Coca-Cola. That study, in the current issue of the medical journal, did acknowledge that there are now some energy drinks that are caffeine free.
"Caffeine is generally considered safe" by the U.S. Food and Drug Administration, the Michigan report says. "Caffeine toxicity is dose dependent and fatalities have been reported at very high dosages" based on body weight, with thinner people having more concentrated amounts of caffeine in their bodies. The risk of serious side effects increases with people who have heart disease or who smoke.
The FDA says that caffeine is mildly addictive and that could be the reason drink makers include it in sodas and other beverages. The agency points out in a report that only 5% of colas made by Coca-Cola are caffeine free, although beverage makers claim caffeine boosts taste.
While not addressing the ingredient of caffeine, energy drink Red Bull's website points out that its products are designed to boost energy, not replenish the body after exertion, and recommends consumers drink plenty of water during exercise.
Another study by researchers at Nova Southeastern University also found that some data suggests combining energy drinks with exercise cuts body fat , but other data contradicted that conclusion. That report, published in April, recommends education on how caffeine affects on the body.
Caffeine in an energy drink can equal 15 Cokes, studies say