Do energy, sports drinks live up to hype?

More from a CBS News discussion with Dr. Jennifer Ashton, a medical correspondent:

WE SEE A LOT OF THE SAME INGREDIENTS IN THESE DRINKS, SUCH AS "TAURINE," "GUARANA," "GREEN TEA LEAF EXTRACT," B-VITAMINS. WHAT DO THEY DO?

Guarana is a natural source of caffeine. Green Tea Leaf Extract, like caffeine, may have an effect on metabolism. Ginseng, Taurine, Gingko and B Vitamins are often thrown into these drinks, but there's little evidence that they offer any benefit for boosting energy or for weight loss.


RED BULL AND ROCKSTAR RELY HEAVILY ON CAFFEINE AS AN INGREDIENT. IS IT SAFE TO CONSUME ALL THAT CAFFEINE?

Safe? For the average healthy adult who uses them on an occasional basis, probably. But the additional caffeine may not be a good idea for some people, such as those with high blood pressure and women with osteoporosis. And these drinks are certainly not recommended for pregnant women, people with heart conditions, or children.

IS VITAMIN WATER BETTER THAN REGULAR WATER?

Waters infused with various vitamins are generally no better than regular water, and in some cases, may be worse, because they contain a lot of sugar. The amount of vitamins you get in a regular serving is a small fraction of what you really need in a day, and the additional sugar can sneak up on you.

HOW ABOUT SPORTS DRINKS, SUCH AS GATORADE?

If you're just doing mild to moderate exercise, you probably don't need a sports drink. But for people who engage in high-intensity workouts and people who sweat a lot, a sports drink may have a role. They provide hydration, fuel (in the form of sugar) and, more importantly, electrolytes such as sodium and potassium that athletes lose through sweat.

BOTTOM LINE, ARE THESE DRINKS NECESSARY, AND ARE THEY SAFE?

It depends. As for the weight loss and energy drinks, I hate to say it but -- we always go back to the basics. Regular exercise and a healthy diet are really the keys to losing weight and maintaining a healthy weight. And I overheard someone say you might as well just drink two cups of coffee and take a multivitamin instead. But these drinks deserve further study. As for the vitamin waters, you're better off sticking with plain water or a no-calorie flavored variety if you want something with taste. And as for sports drinks, they certainly have a place for people who engage in serious sweat-producing activities.