Ever wonder how close to reality come the advertising claims of fitness products? Dr. Matthew Thompson, a senior clinical scientist at the University of Oxford, decided to find out. His conclusion: not so much. Nicholas Bakalar, writing in the New York Times, reports that Thompson and his colleagues examined advertising for sports drinks, oral supplements, footwear, clothing and devices like wrist bands and compression stockings in 100 general–interest magazines and the top 10 sports and fitness magazines, as well as websites, in Britain and the United States. The researchers stopped short of including bodybuilding magazines and advertisements for weight loss, skin or beauty products, and equipment like bicycles and exercise machines. The researchers tried hard to find studies backing up the claims, and even wrote to 42 companies, 27 of which responded. Their scholarly conclusion: There is a striking lack of evidence to support the vast majority of sports-related products that make claims related to enhanced performance or recovery, including drinks, supplements and footwear. Half of all websites for these products provided no evidence for their claims, and of those that do, half of the evidence is not suitable for critical appraisal. No systematic reviews were found, and overall, the evidence base was judged to be at high risk of bias. Half of the trials were not randomised, and only 7% reported adequate allocation concealment. We found only three trials that were reported with sufficient details to be judged high quality and free from bias. Download the study here. Read more in the New York Times.