Adolescent Update: Energy Drinks in Children and Adolescents
By Chung A. Lee, MD, PhD; edited by Katie Plax, MD, director, division of diagnostic and adolescent medicine
The Adolescent Center is an outpatient clinic developed to assist health care providers in the prompt assessment and care of patients 12-21 through consultations, evaluation, treatment and education. The center may be reached at 314.678.4357.
Energy drinks have become one of the fastest-growing items in the U.S. beverage industry. Americans spent $5.4 billion on energy drinks in 2006, and its market presence has nearly doubled since then. Not surprisingly, approximately half of the market consists of those under age 25, with a significant portion of the demographic comprised of children and adolescents. Unlike soft drinks, with caffeine content limited to 71 mg of caffeine per 12 fluid ounces of soda by the Food and Drug Administration (FDA), energy drinks are classified as “dietary supplements,” that are not stringently regulated. As such, energy drinks often contain far higher amounts of caffeine (up to five times greater than average soft drinks), as well as a multitude of additives marketed to increase energy or burn fat.
Caffeine affects numerous molecular pathways, acting as an adenosine and benzodiazepine receptor antagonist, phosphodiesterase inhibitor and central nervous system (CNS) stimulant. Physiologically, this translates into coronary and cerebral vasoconstriction, smooth muscle relaxation, as well as cardiac chronotropy and inotropy. Caffeine also acts as a mild diuretic, although intake of <500 mg/day should not cause dehydration. Though few studies have investigated safe levels of caffeine in children, toxicity in adults begins at 1 gram. A lethal dose is considered to be 200-400 mg/kg.
Energy drinks commonly contain additional ingredients that purportedly increase one’s energy and/or metabolism. Guarana is a South American plant commonly boasted in energy drinks. It contains significant quantities of caffeine (1 gram of guarana can contain 40-80 mg of caffeine), theobromine (a chronotrope) and theophylline (an inotrope), and its physiologic effects reflect this. Taurine is another common additive to energy drinks and is an organic acid derived from cysteine. Its role in the body is widespread, including cardiovascular function, development of skeletal muscle, the retina and the CNS. Studies have shown a cardiac inotropic effect in adults, with one study abandoned secondary to patients becoming dizzy. L-carnitine is synthesized from lysine and methionine involved in the oxidation of fatty acids. At high doses it has been shown to cause nausea, vomiting, diarrhea and abdominal pain, as well as seizures. Yohimbine is an alkaloid extracted from the bark of the West African evergreen pausinystalia yohimbe. Marketed to increase energy and metabolism and purported to be an aphrodisiac, it can cause hypertension, tachycardia, seizures and even death at high doses.
Only since 2010 has the United States specifically tracked adverse effects of energy drinks. One recent case report describes a 17-year-old male who ingested 3L of energy drink mixed with 1L of vodka. This equated to 4,600 mg of taurine, 780 mg of caffeine and 380 grams of alcohol. He presented in acute renal failure and spent a total of 10 days hospitalized before being discharged. Several other countries, including Germany, Ireland and New Zealand, have documented outcomes attributed to the consumption of energy drinks, including liver and kidney damage, respiratory disorders, agitation, seizures, rhabdomyolysis, tachycardia, hypertension, heart failure, arrhythmias and even death. Because of these potentially severe outcomes, many countries have elected to ban some or all energy drinks (e.g., Australia, Denmark, Germany, Turkey), while others have instituted restrictions on their sale based on age or caffeine content.
A review published in 2011 by the American Academy of Pediatrics concluded that energy drinks have “no therapeutic benefit, and both the known and unknown pharmacology of various ingredients, combined with reports of toxicity, suggest that these drinks may put some children at risk for serious adverse health effects.” As pediatricians, our role is to be mindful that use of energy drinks is rising and potentially dangerous for those children with pre-existing cardiac or renal conditions. Further research is required to elucidate the long-term effects of energy drink consumption.
- Seifert, S.M. et al. Health Effects of Energy Drinks on Children, Adolescents and Young Adults. Pediatrics. 2011; 127(3):511-528.
- Committee on Nutrition and the Council on Sports Medicine and Fitness. Sports Drinks and Energy Drinks for Children and Adolescents: Are They Appropriate? Pediatrics. 2011; 127(6): 1182-1189.
- Schoffl, I. et al. “Vodka Energy”: Too Much for the Adolescent Nephron? Pediatrics. 2011; 128(1): e227-231.