Coconut water, the latest thing on the 'health halo' list Every couple of years a food or beverage is crowned with what nutrition experts call a "health halo." Some of the foods - wild salmon, blueberries, flax seeds - deserve it. But others gain status for no apparent reason. Acai berry, anyone? It's not that the trendy food is unhealthful. It's just that if you're already eating a well-balanced diet it's unnecessary. And possibly expensive. The latest entrant in this category: coconut water. Coconut water - the mildly sweet liquid from the center of young, green coconuts - has been popular in tropical areas since, well, as long as people have lived among coconut palm trees. In recent years it has found its way onto the shelves of mainstream grocery stores, often with fruit juice or sugar added. A 14-ounce serving can cost as much as $3.50. "Coconut water is a good source of potassium, but bananas and potatoes contain just as much or even more, and they're much less expensive," says Joan Salge Blake, a registered dietitian and clinical associate professor of nutrition at Boston University. It's true that many Americans fall short of the recommended daily intake of potassium, but Blake says there are better ways to meet the requirement. With the potassium-rich whole foods you also get fiber and other nutrients, which is why I prefer them. People can certainly eat the "meat" of the coconut for potassium and fiber, but they'll also get 26 grams of saturated fat per cup. We depend on potassium for muscle function, and that's why coconut water is marketed as an alternative to sports beverages. At a presentation during the American Chemical Society's annual meeting last month, researchers reported that coconut water is a viable sugar-free substitute for drinks such as Powerade and Gatorade. "In addition to potassium, coconut water contains other electrolytes that are lost during exercise," says Chhandashri Bhattacharya, a chemist at Indiana University Southeast who made the presentation. Coconut water is also a low-glycemic food, meaning it won't cause spikes in blood sugar. Bhattacharya's study echoed findings from a 2012 study in the Journal of the International Society of Sports Nutrition. The earlier study found that coconut water is as effective at rehydrating athletes after an intense workout as bottled water and sports beverages. The one thing that coconut water doesn't do for athletes is replace the sodium that is lost during strenuous exercise that lasts longer than an hour. "You can eat a couple of salty crackers to get what you need," says Andrea N. Giancoli, a Los Angeles-based registered dietitian and spokeswoman for the Academy of Nutrition and Dietetics. The thing Giancoli wants everyone to remember is that there is not one food or drink that the human body needs above all others. "If you like it and you can afford it, there's nothing wrong with coconut water, as long as you're choosing a brand without added sugar," she says. The last thing we want people to do is find another way to drink calories.