This clear liquid is hailed as a natural alternative to your sports drinks but does it live up to the hype, asks Peta Bee

Who hasn’t heard of coconut water? A favourite of athletes and celebrities alike (Madonna liked it so much she invested in a coconut water brand) among those looking for a natural means of rehydration, it is free from the garish colours and artificial preservatives you find in many energy drinks.

Its commercial appeal has sparked a coconut-water “war” among drinks manufacturers. There are currently almost 30 brands on offer in Britain and sales of Vita Coco, the biggest name, grew by 168% last year, making it the fastest-growing non-alcoholic drink. Yet our thirst for it could be tempered by suggestions that coconut water is not all it is cracked up to be.

What’s in it?

What sets coconut water apart from other drinks, claim proponents, is its purity. Apparently, it is an unadulterated source of electrolytes, including sodium, potassium, magnesium and phosphate. The nut-flavoured juice is 94% water, but it also contains plant hormones, enzymes and B vitamins.

It is said to contain the same roster of salts and minerals lost through sweat, all adding to its appeal for athletes.

Any proof?

What rankles with exercise scientists and nutritionists is that few of the claims made by manufacturers are substantiated and the evidence for its benefits is mostly anecdotal. Studies on coconut water are small, sparse and often industry-funded. Of those that are published, results do not support the hype.

“A lot of excitement has arisen from a few insignificant studies,” says Nicole Rothband, of the British Dietetic Association (BDA). A study in the Journal of the International Society of Sports Nutrition reported little difference between bottled water, sports drinks and two varieties of coconut water when it came to boosting exercise performance or hydration.

Not always what it seems

In another study, presented to the American Chemical Society, Dr Chhandashri Bhattacharya of Indiana University compared the nutritional make-up of coconut water with that of Gatorade and Powerade. Her findings showed that the coconut drink contained 1500mg of potassium per litre, five times more than the sports drinks. However, it fell short on levels of sodium lost in sweat, containing 400mg per litre, whereas the energy drinks had 600mg per litre, so athletes who sweat a lot would need to add salt to their coconut drink to make it effective.

Short on sodium

Many commercial coconut drinks contain less sodium than is found in juice sipped straight from the coconut or in a regular sports drink. In 2011, an analysis by the independent product-testing company found that two of the three most popular brands of coconut water contained far fewer electrolytes than indicated on their labels.

One brand had only 18% of the promised level of sodium, leading ConsumerLab’s Dr Tod Cooperman, who headed the trial, to warn: “People shouldn’t count on coconut water for serious rehydration.”

Worth a try?

Linia Patel, a sports dietician with the BDA explained more: “Drink coconut water if you like it, but it is probably not the best drink you could choose to sip after training. In addition to fluid, what is needed when you work out with intensity is carbohydrate in the form of sugars to replenish energy stores, and some sodium to enhance fluid absorption and replace sweat losses.

“Coconut water has some, but not in the optimum ratio to support intense activity.”