One of the best parts of my job as a sports dietitian is sifting through new products for endurance athletes and evaluating their claims as facts or fiction.
Since most products fall into the “bogus” category, imagine my delight to see coconut water touted as “an all-natural, super-hydrating, nutrient-packed, potassium-stacked, mega-electrolyte” sports drink.
Why? Because most of that statement is true. Coconut water, which is the clear liquid that sloshes around inside a coconut, really is high in potassium. One cup provides about 500 mg of potassium along with reasonable amounts of sodium and magnesium, and smaller amounts of phosphorous and vitamin C. Natural sugars give it a mildly sweet taste and there’s no fat or cholesterol.
It's no wonder that numerous beverage companies now sell coconut water in bottles and cans, touting it as a “natural” sports drink.
But like many other nutrition products, what starts off as a great idea, ends up as another fad that quickly fades into oblivion before you know it.
One of the problems with bottled or canned coconut water is that they don’t always contain what they say they contain. According to a recent product review by ConsumerLab.com, an independent product testing company, two out of the three coconut water products they tested had significantly less sodium and potassium than what their labels claimed they had.
This is important because the primary electrolyte we lose in our sweat is sodium and it needs to be replaced in long endurance events, especially for those who sweat heavily.
One package of O.N.E. Coconut Water had only 11 mg of sodium, much less than the 60mg stated on the label and a whole lot less than the recommended 240 mg per serving it would need to be called a good sport drink.
Coconut water is low in carbohydrate too so it would not be a good recovery drink. After a hard workout, you need to replenish your glycogen stores with carbohydrates and coconut water just doesn’t have enough to do that effectively. You’re better off with real food or a fruit-based protein smoothie to refuel your muscles than coconut water.
Another problem with coconut water is that it has a mild laxative effect in some athletes, most likely due to its high magnesium content. Obviously this is not what you want in the middle of a long training run or race!
Lastly, coconut water is expensive. A 414 mL bottle of Zico Natural Coconut Water is $2.50, a pricey way to get the same nutrients you’d get in a banana and some pretzels.
Bottom line? Coconut water is a much healthier alternative to soda pop or sweetened fruit drinks and would be fine to drink before working out. But it is not an effective sports drink for improving performance and recovery because of the low sodium and low carbohydrate content. It’s better to make your own sports drink or stick to the traditional sports drinks for events longer than 90 minutes and/or events in very hot weather. Drink up!