Coconut Water, A New Sports Drink?
The next time you work out at the gym or jog around the park, you may want to rehydrate yourself with some refreshing coconut water. A new report presented at the 244th National Meeting & Exposition of the American Chemical Society, along with some previous research, indicate this tropical treat gives sports drinks a run for their money.
Where does coconut water come from?
This may sound like a ridiculous question, but coconut water isn't derived from just any coconut: it must be immature, green coconuts. Why? Because when coconuts mature, the coconut water turns into coconut milk, a sweet, very high-calorie, high-fat beverage not designed to quench your thirst or rehydrate you after exercise.
Coconut water is not calorie-free like bottled water, but it offers fewer calories than sports drinks and some more electrolytes. Eight ounces of coconut water provides about 46 calories, 3 grams of fiber, 600 mg potassium, 325 mg sodium, 57.6 mg calcium, and 60 mg magnesium.
For comparison, 8 ounces of Gatorade fruit-flavored thirst quencher contains 63 calories, 0 grams of fiber, 36.6 mg potassium, 95.2 mg sodium, 2.4 mg calcium, and 0 mg magnesium. (Not all sports drinks and thirst quenchers are the same; you need to read the labels.)
At the American Chemical Society gathering, Chhandashri Bhattacharya, PhD, of Indiana University Southeast in New Albany, explained the latest findings of her research team, who evaluated coconut water, Powerade and Gatorade.
She noted that "coconut water is a natural drink that has everything your average sports drinks has and more," including "five times more potassium than Gatorade or Powerade." Their analysis showed up to 1,500 mg per liter of potassium in coconut water compared with up to 300 mg per liter for the branded sports drinks.
In addition to helping prevent or relieve muscle cramping associated with exercise, potassium is also important for the heart. Too little of this mineral, especially in the presence of high sodium (and the American diet is too high in salt) can result in an unhealthy balance between these two nutrients and increase the risk of heart disease and death from all causes.
The samples analyzed by the team showed coconut water had 400 mg per liter of sodium compared with 600 mg for the sports drinks, and that the amounts of magnesium and carbohydrates were similar among the three beverages. However, given the wide range of products on the market, consumers would be wise to carefully read the ingredient labels on any coconut water or sports drink before making a purchase.
In fact, Bhattacharya noted that the coconut water in their study had a sodium level that was too low to qualify it as a good sports drink for people who participate in vigorous exercise that would make them lose more sodium than potassium. What was not mentioned, however, was the possibility of drinking sodium-enriched coconut water, as was used in another study, discussed below.
Other coconut water studies
In an early crossover study, ten healthy men consumed plain water, sports drink, coconut water, or sodium-enriched coconut water after 90 minutes and losing about 3 percent body weight. Results showed the sodium-enriched coconut water was equal to the sports drink for whole body rehydration, but fluid tolerance was better than the sports drink. The sodium-enriched coconut water also caused less nausea and stomach distress compared with the sports drink and plain water.
In a subsequent study, conducted at the University of Memphis, investigators evaluated the efficacy of bottled water, pure coconut water, coconut water from concentrate, and a carbohydrate-electrolyte sports drink in 12 healthy young men (average age 26.6 years). Each man participated in four different 60-minute exercise sessions, separated by at least five days, after which they consumed one of the four beverages so that each man had each liquid one time.
The men lost about 2 percent of body mass during each session and regained it after consuming the different beverages. Both coconut water beverages and the sports drink were similar for fluid retention. The researchers also saw no significant difference between the bottle water, either coconut water beverages, and the sports drink in terms of exercise performance.
Overall, the authors concluded that "all tested beverages are capable of promoting rehydration and supporting subsequent exercise." When the men consumed the coconut water products, however, they did report feeling more bloated and having some stomach distress.
The next time you need to rehydrate after exercise, you may want to consider coconut water instead of a sugary sports drink, and enjoy a little tropical twist as you recover.
American Chemical Society
Ismail I et al. Rehydration with sodium-enriched coconut water after exercise-induced dehydration. Southwest Asian Journal of Tropical Medicine and Public Health 2007 Jul; 38(4): 769-85
Kalman DS et al. Comparison of coconut water and a carbohydrate-electrolyte sport drink on measures of hydration and physical performance in exercise-trained men. Journal of the International Society of Sports Nutrition 2012 Jan 18; (1): 1
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