The Buzz on Energy Drinks

Energy drinks and nutrition bars often make big promises. Some say they'll increase energy and alertness, others offer extra nutrition, and some even claim to boost your athletic performance or powers of concentration.

But once you cut through the hype and look past the flashy packaging on energy products, chances are what you're mostly getting is a stiff dose of sugar and caffeine.

As if that wasn't enough, some of these beverages additionally contain herbal stimulants, such as guarana, ginseng, and yerba mate. You might be thinking, well, so what? Isn't drinking a can of Red Bull or Full Throttle just like drinking a can of Coca-Cola? Not necessarily.

What are the risks of these energy drinks? A study published earlier this year in The Annals of Pharmacotherapy found that healthy, young adults who drank two cans of an energy drink each day for five consecutive days had increases in blood pressure and heart rate, which the researchers attributed to both caffeine and taurine. (The subjects were sedentary throughout the study.) While the increases were not considered significant, the findings could prove dangerous to people who have high blood pressure or heart disease.

Why weight gain? With the exception of a few sugar-free versions, these drinks contain calories and carbohydrate. For example, one 8.3-ounce serving of Red Bull contains 113 calories and 28 grams of carbohydrate; one 8-ounce serving of Monster Energy has 100 calories and 27 grams of carbohydrate; and one 8-ounce serving of Original Rockstar Energy has 140 calories and 31 grams of carbohydrate.