Members of the men's swim team at Midlakes High School in Rochester, N.Y., would often complain of feeling dizzy, shaky and hyper during practice; sometimes they'd vomit in the middle of a workout.
Coach R.C. Weston knew their sickness wasn't related to lack of conditioning or overtraining. "It was directly related to their consumption of energy drinks," he said.
The swimmers admitted that downing an energy drink before practice didn't help their performance -- in fact they were left feeling unfocused and dehydrated -- but they drank them anyway because they "taste amazing" and the "heightened sensation makes you feel more energetic." Team members are now banned from drinking them while in training.
A new report by University of Miami experts in the March issue of Journal Pediatrics, published online today, warns that caffeine-containing energy drinks like Red Bull, Rock Star and Monster -- not to be confused with sports drinks like Gatorade -- may do more than just give young athletes the jitters. They may harm the health of children, especially those with diabetes, seizures, cardiac abnormalities or mood and behavior disorders. Energy drink overdoses in children as young as 5 have been reported both here and abroad and in some cases have resulted in seizures, stroke and even sudden death.
While the paper contains no new information per se, lead author and pediatrician, Dr. Steven E. Lipshultz, said he believed this was the first systematic review of the effects of energy drinks on children 19 and younger. "We looked at 121 sources. More than two-thirds were previously published scientific literature plus government agency and special interest group reports; the rest were the websites and marketing materials from the markers of energy drinks," Lipshultz explained.
Lipshultz said the authors wanted to create a comprehensive resource for pediatricians, sports coaches and families to get accurate information about what's in energy drinks and what problems they can cause for young people. Energy drinks are the fastest growing U.S. beverage market with sales expected to top $9 billion in year 2011. More than half the market is under 25 years of age and 30-50 percent of adolescents and young adults consume energy drinks. A quick perusal of packaging, websites and marketing material for the beverages shows they are clearly aimed at the youth market.
Manufacturers of the popular beverages bristled at the notion that the products could put young people's health at risk. Jack Owoc, the CEO of VPX, the company that produces the Redline series of energy drinks, objected to the idea that all high-caffeine beverages should be measured by the same standard. He said his line of beverages -- some of which contain 250 mg of caffeine per 8-ounce can -- are dietary supplements and that the drinks already contain package warnings that they are not for sale to those younger than 18.
"Redline is a dietary supplement and dietary supplements fall under strict [good manufacturing practice] guidelines set forth by the FDA," Owoc said in a statement. "Whatever the guidelines the FDA sets up we will gladly follow."
In a written response, Maureen Storey, senior vice president of science policy at the American Beverage Association, an industry group, said the report "does nothing more than perpetuate misinformation" about energy drinks.
She wrote that many of the drinks contain much less caffeine than coffee from popular coffeehouses, and caffeine amounts are listed on many of the products.
The response from Red Bull added that because "an 8.4-ounce can of Red Bull contains about the same amount of caffeine as a cup of coffee (80mg), it should be treated accordingly."
Still, the report found that high caffeine content has been associated with serious adverse effects especially in youngsters who have underlying health condition. "The labels on these products sometimes list a general caffeine content instead of giving you exact milligrams," warned Dr. Marcie Schneider, one of the pediatricians on the nutrition review board of the American Academy of Pediatricians, the group that published the paper. "They often don't account for the caffeine in some of the other chemicals which can be fairly significant."
Although the FDA limits caffeine content in soft drinks, which are categorized as food, there is no such regulation of energy drinks which are categorized as dietary supplements.
"Because kids are smaller, the recommended dose of caffeine that's safe is lower," noted Tara Harwood, pediatric nutritionist at the Cleveland Clinic. "So for the average adult, what is recommended is less than 400 mg of caffeine per day. But in kids, they recommend less than 100 mg of caffeine per day. And the average energy drink, for 8 ounces has about 80 mg of caffeine. So for one 8-ounce can that's putting you close to that limit. Energy drinks do have about three times the caffeine of a regular soda."
Harwood added, "We don't really have studies on the effects of caffeine on a developing brain or all the developing organs in a kid and how that can actually affect them. Especially in some of the mood disorders, such as ADHD, we don't really know its effects yet. So it's not really regulated and it's really understudied."
And caffeine is just one of the many issues many experts have with these beverages. For example, one common ingredient, the herb guarana, contains three times the caffeine as coffee, and has been known to cause difficulty urinating, vomiting, and abdominal cramps, spasms and most seriously, heart arrhythmias. Yohimbine, another typical ingredient, can cause rapid heart rate and high blood pressure in usual doses and even death in susceptible individuals. Theobromine, a compound similar in its effects to caffeine, speeds up heart rate and frequently leads to sleeplessness, tremors, restlessness and anxiety. Until several overdose deaths were reported, the diet drug ephedra was also a common additive.
"These ingredients in and of themselves may have undesired side effects," Schneider cautioned. "We also don't know how each of these chemicals may potentiate the others."
The authors argue that because energy drinks have no therapeutic benefit in children and may actually put some children at risk for adverse health events, these products need to be better studied and more tightly regulated particularly for certain populations. They also recommend better education and awareness.
Cheri Kauffman is one parent who wasn't aware of the potential dangers of the beverages. Though she hasn't had time to investigate them as thoroughly as she'd like, she allowed her children to have a limited amount of energy drink daily. She said her 12-year-old begged her for months to let him try Monster. Finally, on a family trip he wore her down and she allowed him to run into a gas station to buy one. "Now he's been drinking about a can a day for a month and he's much more energized and easier to deal with when he drinks part of a can in the morning, kind of like me after I've had a cup of coffee."
Kauffman confessed one of her biggest worries is whether the drinks are addictive. "It's the first thing he asks for when I pick him up from school. When we get low on it, it practically puts him into a panic," she admitted.
Tony Reynolds, who has six sons, said he has permitted his kids to drink up to one eight ounce can per day. "The younger kids -- 10 and 8 -- were bouncing off the walls and running in circles already so these really hyped them up. With older boys the energy spikes weren't as noticeable." He has stopped giving them to the two youngest but thought the older kids could digest them like it was coffee.
Other parents are clearly more concerned. When Kauffman's son gave a can of Monster to another child at school, the boy's mother was incensed. "She called the school and accused my son of 'dealing energy drinks'," Kauffman said. Since it's legal for anyone to buy the drinks and the school does not have an outright ban, the principal let him off with a warning.
Kauffman noted that the students have learned to hide them in their backpacks and drink them surreptitiously while at school.
Lipshultz felt that the safety concern about energy drinks is so important his report is being made free to the public on the American Academy of Pediatrics website. "While we know they can cause health risks, they have no known therapeutic effects and therefore there are no health reasons for drinking them," he pointed out.
He urges parents, educators and pediatricians to monitor their children's consumption. "They're asked cigarettes and drug use. They should be asked about energy drinks too."