A team at Oxford University, led by Dr Carl Heneghan of the Oxford University Centre for Evidence-Based Medicine, called for better studies to make consumers more aware of how certain products affect their wellness, after they analysed 431 claims in 104 sport product adverts and finding a ‘worrying’ lack of high-quality research.
For example, Lucozade Sport, the UK’s best-selling sports drink, is advertised as giving you ‘an isotonic performance fuel to take you faster, stronger, for longer’. When the team of researchers asked manufacturer GlaxoSmithKline (GSK) for details of the science behind their claims, they were given what scientists call a ‘data dump’ of 40 years’ worth of Lucozade sports research which included 176 studies.
In this mountain of data, Dr Heneghan said the team was able to examine 101 trials before concluding: ‘In this case, the quality of the evidence is poor, the size of the effect is often minuscule and it certainly doesn’t apply to the population at large who are buying these products. Basically, when you look at the evidence in the general population, it does not say that exercise is improved [or that] performance is improved by carbohydrate drinks.’
GlaxoSmithKline responded by saying, ‘Over 40 years of research experience and 85 peer-reviewed studies have supported the development of Lucozade Sport and all our claims are based on scientific evidence that have been reviewed and substantiated by the European Food Safety Authority.’ GSK also manufacturers the Maxinutrition range of sports supplements, which contain the branch chain amino acids found in muscle protein. The company says these amino acids ‘help hard-training athletes recover faster after intense exercise.’
However, the Oxford research team and the British Medical Journal said there’s no evidence to support this: ‘The evidence does not stack up and the quality of the evidence does not allow us to say these do improve in performance or recovery and should be used as a product widely,’ said Dr Heneghan.