Low in calories, naturally free of fat and cholesterol, more potassium than four bananas, and super hydrating -- these are just a few of the many benefits ascribed to America’s latest health craze: coconut water.
Dubbed "Mother Nature’s sports drink" by marketers, the demand is skyrocketing, propelled by celebrity and athlete endorsements and promises to hydrate the body and help with a whole host of conditions, from hangovers to cancer and kidney stones.
But is coconut water capable of delivering on all the promises, or is all of this hype?
What Is Coconut Water?
Naturally refreshing, coconut water has a sweet, nutty taste. It contains easily digested carbohydrates in the form of sugar and electrolytes. Not to be confused with high-fat coconut milk or oil, coconut water is a clear liquid in the fruit’s center that is tapped from young, green coconuts.
It has fewer calories, less sodium, and more potassium than a sports drink. Ounce per ounce, most unflavored coconut water contains 5.45 calories, 1.3 grams of sugar, 61 milligrams of potassium, and 5.45 milligrams of sodium. In comparison, Gatorade has 6.25 calories, 1.75 grams of sugar, 3.75 milligrams of potassium, and 13.75 milligrams of sodium.
Better Than Some Sugary Drinks
Coconut water has less sugar than many sports drinks and much less sugar than sodas and some fruit juices. Plain coconut water could be a better choice for adults and kids looking for a beverage that is less sweet. But don’t overdo it, says Lilian Cheung, DSc, of Harvard School of Public Health. “One 11-ounce container has 60 calories, and if you drink several in one day, the calories can add up quickly," she says.
Cheung, a registered dietitian and co-author of Savor: Mindful Eating, Mindful Life, suggests being mindful about beverage choices and reading labels to choose plain coconut water and avoid those with added sugar or juices, which are no different from other sugary beverages.
Some Athletes Swear By It
Professional tennis player John Isner credits coconut water with keeping him on his feet for his epic 11-hour marathon Wimbledon tennis win. “It is super hydrating and has kept me going in long matches and prevented me from cramping even in the hottest and most humid conditions,” he says.
He drinks a mixture of coconut water and water the night before a match in difficult heat conditions; he routinely mixes a cocktail of coconut water and sea salt for on-court hydration; and he mixes it with protein powder for post-match recovery.
Coconut water may be better at replacing lost fluids than a sports drink or water -- as long as you enjoy the taste. A study recently published in Medicine & Science in Sports & Exercise shows that coconut water replenishes body fluids as well as a sports drink and better than water, but athletes preferred the taste of sports drinks.
Sports nutritionist Nancy Clark, author of Nancy Clark's Sports Nutrition Guidebook, says coconut water won’t rehydrate the body unless you can drink plenty of it. If you enjoy the taste and can tolerate large amounts, it could help keep you hydrated.
A 2007 study shows coconut water enhanced with sodium was as good as drinking a commercial sports drink for post-exercise rehydration with better fluid tolerance. Another study reported that coconut water caused less nausea, fullness, and stomach upset and was easier to consume in large amounts during rehydration.
What Experts Say
Staying hydrated is one of the most important things for recreational and professional athletes. And if the taste of coconut water helps you drink plenty of fluids, it is a fine choice for most people but may not be for those in prolonged physical activity.
Coconut water is low in carbohydrates and sodium and rich in potassium, which is not exactly what athletes need when exercising rigorously, says Clark.
“Whether you choose a sports drink, coconut water, or plain water, they all work to keep your body hydrated. The challenge is when you exercise strenuously for more than 3 hours in the heat and lose lots of body fluids, you need easily absorbed carbs for quick energy and to replace lost electrolytes like sodium and potassium,” she says.
Neither coconut water nor sports drinks contain enough sodium or carbs for the heavy perspirer. “Supplement with a quick source of energy like a banana or some raisins and a handful of pretzels to provide nutrients to replenish your stores,” Clark says.
Recovery starts before exercise begins. “Most people don’t need to worry about calories, potassium, or sodium. Eat a bagel with peanut butter to get food into your system before and drink plenty of water during exercise,” Clark says. If you exercise for prolonged periods, she suggests eating salty pretzels and raisins or other portable sources of energy.
There are some health benefits to drinking coconut water. It’s an all-natural way to hydrate, cut sodium, and add potassium to diets. Most Americans don’t get enough potassium because they don’t eat enough fruits, vegetables, or dairy, so coconut water can help fill in the nutritional gaps.
Beyond that, the scientific literature does not support the hype that it will help with a laundry list of diseases. “There is a lot of hype about coconut water, yet the research is just not there to support many of the claims, and much more research is needed,” says Cheung.
Coconut water is fine for recreational athletes -- but so are plain water and sports drinks. In general, most adults don’t exercise strenuously enough to need sports drinks or coconut water, so good, old-fashioned water works just fine.
If you enjoy the taste and your budget allows it, coconut water is a nutritious and relatively low-calorie way to add potassium to your diet and keep you well-hydrated.
Kathleen Zelman, MPH, RD, is director of nutrition for WebMD. Her opinions and conclusions are her own.