Expert concerns about the popular pick-me-ups.
Tired, stressed-out college students and workers have embraced energy shots, which promise a quick, convenient boost with fewer calories and less sugar than full-size energy drinks.
Sales of the 2- to 3-ounce shots soared to $544 million in 2008, double those of the previous year, according to Information Resources, a Chicago-based market research firm. In fact, energy shots are the fastest-growing segment of the $4.6 billion energy drink market.
Living Essentials pioneered energy shots in 2004 with 5-Hour Energy, which still holds more than 75% of the market. Industry heavyweights such as Red Bull, Monster Energy, and Coca-Cola have since introduced their own energy shots. Their ingredients vary, but most contain caffeine, B vitamins, and taurine (an amino acid found in food from animal sources) as well as flavorings and artificial sweeteners.
The sugar-free shots are not only portable but also lower in calories than most energy drinks. The 2-ounce 5-Hour Energy shot, which is artificially sweetened, has 4 calories. A regular 8-ounce Red Bull energy drink, by comparison, has 100 calories, and a sugar-free Red Bull has 10 calories.
The shots tend to have about as much caffeine as regular energy drinks, and it's the caffeine that provides most of the kick, experts say. Because of that, nutritionists urge caution, especially for those who also drink coffee or other caffeinated drinks.
Jim White, RD, a national spokesman for the Academy of Nutrition and Dietetics, says, "I’m seeing a lot of combinations -- coffee, 5-Hour Energy, green teas -- and if you add up all the mega doses of caffeine during the day, it can cause problems."
Specifically, too much caffeine can cause nervousness, trouble sleeping, nausea, vomiting, rapid heartbeats, and higher blood pressure. Many makers of energy shots say children and those who are pregnant, nursing, or sensitive to caffeine should avoid the beverages. 5-Hour Energy advises no more than two bottles a day.
Energy shot makers are not required to disclose their products' caffeine content, although a group of scientists has petitioned the FDA to require that this information be listed on labels.