Coconut water, which has long been a popular drink in the tropics, is now being offered by trendy bottlers and touted as a source of nutrition, wellness, beauty and hydration.

The juice inside immature coconuts is sometimes billed as "nature's sports drink" and it gets credit for improving circulation, slowing aging, fighting viruses, boosting immunity, and reducing the risk of cancer, heart disease and stroke, according to a recent Los Angeles Times article.

However, Liz Applegate, the director of sports nutrition at UC Davis, shared a more moderate view with Times' reporter Elena Conis.

"There's nothing magical about coconut water," Applegate was quoted. There's no harm in it either.

Coconut water is 95 percent water and contains sodium, potassium, magnesium, calcium, phosphate, and small amounts of many essential amino acids. One cup has 6 grams of sugar, 2 grams of protein and 46 calories.

Even though it is said to have a slightly sour flavor, it has become popular among fitness junkies who don't want to consume sports drinks with artificial colors or preservatives, Applegate told the reporter.

However, coconut water contains up to 15 times as much potassium as the average sports drink. Because the body loses more sodium than potassium during a workout, all that extra potassium isn't important.

The bottom line: Coconut water is fine for casual athletes who like the taste, but there are cheaper ways to rehydrate and restore electrolytes.