Caffeine-infused waffles and maple syrup are being promoted as energizing alternatives to a morning mug of coffee.
But the recent craze of adding caffeine to a range of kid-friendly snack foods — including popcorn, chewing gum, candy bars, mints, Cracker Jacks, jelly beans and ice cream — is raising enough concern that the U.S. Food and Drug Administration (FDA) has launched an investigation of caffeine’s possible health effects on children and adolescents.
The effort, which comes amid the heated debate over whether energy drinks with stimulants are safe for children, marks the agency’s first close look at the world’s most popular psychoactive drug since its use in Cola was approved in the 1950s.
Most healthy adults can safely tolerate moderate doses of 200 to 300 milligrams, which is about two to four cups of brewed coffee, according to the National Institutes of Health. But the U.S. lacks official guidelines or limits for children, whose smaller bodies and developing brains may be more vulnerable to caffeine’s effects, including the risk of physical dependence and addiction.
Part of what worries the FDA is the changing nature of how caffeine is delivered — through a greater array of products that may appeal to younger consumers and in higher doses than in the past.
Chewing a pack of Jolt Energy Gum, for example, would have effects similar to downing six energy drinks, according to the package.
“It’s a question of finding caffeine in new and different places,” said Michael Taylor, the FDA’s deputy commissioner for food. “There are concerns over the perhaps subtle developmental impacts on kids and whether they become regular users of a central nervous system stimulant. What are the cumulative effects?”
Meanwhile, parents can’t necessarily tell how much caffeine kids are getting. Caffeine levels aren’t required to be disclosed on food labels, and if the caffeine occurs naturally — as in tea or cocoa — it isn’t listed among the ingredients.
In the case of energy drinks, many are sold as dietary supplements and don’t have to disclose caffeine levels if the ingredient is part of a “proprietary blend.”
Last month Wrigley, the world’s largest gum manufacturer and a subsidiary of Mars Inc., temporarily halted sales of its new caffeinated gum product after meeting with the FDA. The company cited a “greater appreciation” for the agency’s concern about the recent flood of caffeine in the nation’s food supply.
Others say caffeine has been safely consumed in a variety of foods and beverages for centuries. Many of the newly caffeinated snacks are novelty items targeting adults who want a quick pick-me-up but don’t like coffee.
"If you want to worry about what kids are ingesting, I would put sugar way up higher on the list," said Dr. Jeffrey Goldberger, director of clinical cardiac electrophysiology research at Northwestern Memorial Hospital. "Sugar has clearly documented downstream effects on health that caffeine just does not."
Dr. Goldberger also serves as a consultant to the American Beverage Association and the energy drink company Red Bull.
Consumed daily by 80 percent of the world, caffeine is a bitter-tasting nervous system stimulant that occurs naturally in coffee, tea, guarana, and kola nuts. It's thought to work by interfering with a brain chemical called adenosine that facilitates sleep.
Blocking the receptors for adenosine also allows the brain's own stimulants, neurotransmitters dopamine and glutamate, to rev up bodily systems.
"It not only wakes up the brain, but it can increase heart rate," said Dr. Lynn Goldman, a pediatrician and dean of the School of Public Health and Health Services at George Washington University. "When I've seen people with caffeine overdose, they're scared; they end up in the ER because they think they're having a heart attack."
In adults, caffeine use is relatively safe. But the American Academy of Pediatrics recommended in 2011 that children and teenagers steer clear of caffeinated drinks because caffeine interferes with sleep and can increase anxiety, in addition to an increased heart rate.
"Childhood and adolescence is a period of rapid growth in the final stage of brain development; proper sleep and nutrition are essential," said Jennifer Temple, an assistant professor in the School of Public Health and Health Professions at the University of Buffalo who studies children's caffeine use. "Caffeine disrupts sleep patterns, and the excess consumption of soda is associated with poor diet, excess weight and cavities."
Federal officials can't say whether children are ingesting more caffeine than previous years; rigorous studies involving the nation's youngest consumers are lacking.
But the most recent federal data show that children ages 2 to 13 ingested an average of 43.5 milligrams of caffeine a day in 2008. A typical Cola contains about 35 milligrams in a 12-ounce can. Young men between the ages of 14 and 21 consumed 110.5 milligrams per day; women took in slightly less.
Information also is lacking on the physiological, psychological, and behavioral effects of habitual caffeine use by children.
"We can't assume children are small adults; they may have unique responses we don't know about," Ms. Temple said.
Current regulations include the FDA limiting the caffeine content in soft drinks to 71 milligrams per 12 fluid ounces. But manufacturers often circumvent the limit by calling their products dietary supplements; some energy drinks contain as much caffeine as five cups of coffee.
Sales of energy drinks grew by 78 percent from 2006 to 2011, according to the market research firm Mintel, and a recent study in the journal Pediatrics found that half of the energy drink market consists of children, adolescents and young adults.
Energy drink consumption has been associated with elevated blood pressure, altered heart rates and severe cardiac events in children and young adults, especially those with underlying cardiac disease, according to a letter sent to the FDA by more than a dozen prominent researchers and scientists. The highest doses have been linked with caffeine intoxication, resulting in a racing heartbeat, vomiting and cardiac arrhythmias.
Dr. Steven Lipshultz, a pediatric cardiologist at the University of Miami, tells parents that young patients with an underlying heart condition should avoid caffeine because it can stimulate the heart.
"If you're asking a sick heart to work even harder, it may go into a life-threatening heart rhythm," he said.
Dr. Goldberger, an adult cardiologist, downplayed the cardiac risk of energy drinks in his testimony before the Chicago City Council when it considered restricting sales of the products. In 2011, he published research in the American Journal of Medicine that concluded moderate caffeine use was well tolerated in adult patients with known or suspected arrhythmia.
Wheaton, Ill., mom Nancy VanderMolen said she limits caffeine for her preteen daughter because of the girl's heart condition. But she also said she was disappointed that Wrigley pulled its caffeinated gum off the market because she wanted to try it herself.
"If the packaging is good, people with heart conditions would stay away just as they do from Red Bull," Ms. VanderMolen said. "I don't like coffee and need the caffeine boost. I was looking forward to the gum so I could give up soda for good."
That's the sort of customer Roger Sullivan, the founder of Wired Waffles, is targeting. After hearing about a bakery that laced brownies with caffeine, Mr. Sullivan created a caffeinated waffle; later he launched caffeinated maple syrup.