In a reality check article, he said: “One of the key problems with many of the studies into the benefits of sports drinks is that they recruit highly trained volunteers who sustain exercise at high intensity for long periods. But the vast majority of sports drink users train for very few hours per week or exercise at a relatively low intensity (for example walking instead of running during a race). This means the current evidence is not of sufficient quality to inform the public about benefits deriving from sport drinks.
“Even more importantly, as sports drinks rise in popularity among children, they may be contributing to obesity levels. A 500ml bottle of a sports drink typically contains around 20g of sugar (about five teapsoons’ worth) and so represents a large amount of calories entering the body. But endorsements by elite athletes and claims of hydration benefits have meant sports drinks have shrugged off unhealthy associations in many people’s eyes.”
He concluded: “The current evidence is not good enough to inform the public about the benefits and harms of sports products. What we can be almost sure about is that sports drink are not helping turn casual runners into Olympic athletes. In fact, if they avoided these sugar-laden drinks they would be probably be slimmer and so faster.”