Popularity of energy drinks soars, but experts warn against overindulging

Looking for energy from a bottle? You wouldn't be alone. So-called energy drinks have become the fastest selling category in the beverage industry. Americans spent $744 million on these beverages from June 2006 to June 2007—a whopping 34% increase in spending over the previous year.

Energy drinks are quite popular among college students, young adults, and athletes in particular. And it's no wonder. If you need a pick-me-up, you may be drawn to names that promise vigor, like Full Throttle, Amp, Rush, or the most popular, Red Bull.

But there's really no magic formula here. What gives these drinks their jolt is good old-fashioned caffeine. Many contain about as much caffeine as one cup of coffee, along with loads of sugar. A 2007 Consumer Reports analysis, which tested 12 popular energy drinks, found that the amount of caffeine varied from 50 milligrams (mg) to 145 mg per cup (8 ounces). But the bulk of these drinks—nine of the 12— contained between 75 mg and 85 mg of caffeine per cup. As a point of comparison, the researchers reported that coffee has roughly 100 mg of caffeine per cup while 12 ounces of Coca-Cola has 35 mg.

Energy drinks also contain a mix of herbs and substances that are marketed as "energy boosters," such as those discussed in the section above, which haven't actually been proven to increase energy, unless they also contain caffeine.

Some medical experts are concerned that individuals, particularly young people, may steadily consume too many of these drinks—and that so much caffeine, a diuretic, can contribute to dehydration, particularly when mixed with alcohol, which is a popular trend.

A 2007 study raised a different concern. Researchers at Wayne State University found that blood pressure and heart rates increased in healthy adults who drank two cans a day of a popular energy drink that contained 80 mg of caffeine and 1,000 mg of taurine, an amino acid found in protein-rich food. Other studies have also found that caffeine and taurine impacted heart function and blood pressure.

Although the increases did not rise to dangerous levels in the volunteers who participated in the study, researchers warned that the increase could be significant in people with cardiovascular disease or those taking drugs to lower heart rate or blood pressure. They cautioned people who are at risk for heart disease to avoid energy drinks.

Boosting Your Energy

Fatigue, like death and taxes, may indeed be an inescapable part of life. But that doesn't mean you have to take it lying down. Boosting Your Energy is a special health report from Harvard Medical School that provides you with the latest information about fatigue and offers strategies to help you regain the physical and mental energy you need to enjoy life to its fullest.

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