There’s a disturbing trend in beverage consumption in the U.S. involving caffeine, particularly among children and adolescents.
The trend involves rising use of so-called energy drinks and supplements. The marketing of such beverages appears to my eye to be targeting youth in a way reminiscent of the marketing of tobacco products to earlier generations.
When I was in college, I took a course in advanced biochemistry that focused on the biological effects of caffeine. I was amazed to learn how this common dietary substance, found naturally in coffee and tea, influences so many of the body’s tissues.
As a student, my perception was that of a layman: familiar with the widespread use of coffee and tea across all classes and cultures. These beverages have been consumed in the human diet for centuries. Given this history, common sense dictates the safety of this long-standing practice. In fact, I have written of purported health benefits (and precautions) of caffeine use previously in this column.
Suffice it to say, this is a problem of degrees.
The American Academy of Pediatrics recommends caffeine consumption should not exceed 100 milligrams of caffeine per day for adolescents – about the amount of caffeine in an 8 ounce cup of regular brewed coffee or 8 ounce soda. Younger children should be discouraged from regular consumption of caffeine.
The upper limit of caffeine use considered safe in adults is 400 milligrams per day.
Many popular energy drinks tout caffeine levels comparable to coffee, about 80 milligrams per 8 ounces. However, studies have indicated this underestimates the dose by as much as 20 percent. Meanwhile, concentrated “energy boosters” and “energy shots” have caffeine levels in the 200-250 milligram range.
While most caffeine consumption among youth is in the form of soda drinks, youth and young adults represent more than half of all sales of caffeinated energy drinks in the U.S. – and consumption in these groups is on the rise.
Also on the rise are cases of caffeine toxicity presenting to medical providers and emergency rooms. Levels of caffeine intake in excess of 1 gram can produce toxic effects even among adults, among whom caffeine can be lethal when over 10 grams is consumed in a day.
Caffeine is a central nervous system stimulant, and the only such type of drug whose sales to children are unregulated. Caffeine also affects certain biological receptors in the cardiovascular system and other tissues in the body.
In small or moderate doses in the adult diet, caffeine can improve attention, mood and exercise tolerance, though these effects may be attributable to the reversal of caffeine withdrawal in regular users.
Excess intake of caffeine increases heart rate and may produce anxiousness, irritability, sleeplessness and nausea. Withdrawal from caffeine, particularly after regular or high-dose consumption, commonly leads to fatigue and headache.
Intake of toxic levels of caffeine may produce vomiting, seizures, brain swelling, heart arrhythmia, stroke and even death. Fortunately, such adverse effects are not common, but they are on the rise – particularly among youth and young adults.
Dr. Matthew A. Clark is a board-certified physician in internal medicine and pediatrics practicing at the Ute Mountain Ute Health Center in Towaoc.
