{"id":30537,"date":"2012-07-20T10:47:21","date_gmt":"2012-07-20T14:47:21","guid":{"rendered":"http:\/\/blogs.nejm.org\/cardioexchange\/?post_type=voices&p=30537"},"modified":"2012-07-20T10:47:21","modified_gmt":"2012-07-20T14:47:21","slug":"the-bmjs-amazing-shock-and-awe-assault-on-sport-drink-science","status":"publish","type":"post","link":"https:\/\/blogs.nejm.org\/cardioexchange\/2012\/07\/20\/the-bmjs-amazing-shock-and-awe-assault-on-sport-drink-science\/","title":{"rendered":"The BMJ\u2019s Amazing Shock and Awe Assault on Sport Drink Science"},"content":{"rendered":"

CardioExchange welcomes this guest post by Yoni Freedhoff, an assistant professor at the University of Ottawa and founder of Ottawa\u2019s Bariatric Medical Institute. This piece originally appeared on his blog, Weighty Matters<\/a>.<\/em><\/p>\n

wow.<\/p>\n

Wow, WOw, WOW!<\/p>\n

What words would you use when one of the world\u2019s most prominent medical journals publishes not just one article critical of a specific category of food, but seven<\/em> such articles, and those articles conclude that the food is being marketed on the basis of food-industry-funded hype and collusion?<\/p>\n

I\u2019d use the words, \u201cThank You!\u201d<\/p>\n

You\u2019ll definitely hear about it in the news today as the British Medical Journal<\/em> has seven incendiary pieces that are highly critical of sport and energy drinks, their Big Food parents, and the researchers that are conflicted by them.<\/p>\n

The first piece (The evidence underpinning sports performance products: a systematic assessment)<\/a> has researchers analyzing sport-drink advertising and identifying an astonishing 431 performance-enhancing claims for 104 different products. Those claims were \u201cbacked up\u201d by references made on the products\u2019 websites to 146 references. Of those 146, the authors could only find half of them. Of that half:<\/p>\n

“84% were judged to be at high risk of bias”<\/em>,<\/p>\n

while only three were deemed to be of high quality and of low risk of bias. Ultimately, the authors \u2014 not surprisingly \u2014 concluded that:<\/p>\n

“The current evidence is not of suf\ufb01cient quality to inform the public about the bene\ufb01ts and harms of sports products.”<\/em><\/p>\n

In the next article (The truth about sports drinks<\/a>),\u00a0BMJ<\/em>\u2018s Investigations Editor Deborah Cohen explores the funding and financial ties between sports drinks\u2019 parent Big Food companies, professional sport organizations, and expert advisory panels. Her hard-hitting piece is absolutely fascinating and covers how sport-drink-friendly messaging evolved and later became questionably incorporated into official medical and sport recommendations, often by advisory boards with multiple members on sport-drink payrolls.<\/p>\n

Then, the BMJ<\/em> tackles the\u00a0European Food Safety Authority\u2019s criteria for sport-drink claims (How valid is the EFSA\u2019s assessment of sports drinks?<\/a>). The authors were highly critical of the two claims approved by the EFSA: that sport drinks \u201cimproved water absorption during exercise\u201d and that they helped with \u201cmaintenance of endurance performance.” They state that the EFSA asked Big Food to supply the references upon which their decision was based, that they had no formal criteria to evaluate which studies warranted inclusion in the analysis (Big Food submitted non-peer-reviewed book chapters, opinion pieces, etc.), and that, of those studies supplied to the EFSA, many were absent methodologies.<\/p>\n

For the \u201cimproved water absorption during exercise\u201d claim, the authors combed through the only 22 scientific studies presented to the EFSA and concluded that 17 were of poor quality, the subjects were predominantly male, only 3 studies included people over the age of 30, and not one had an outcome that included performance in a race or a sporting event.<\/p>\n

For the \u201cmaintenance of endurance\u201d claim, there were 26 scientific studies of which 19 were deemed to be of poor quality, 89% of the subjects were men, 73% of the subjects were endurance-trained men, 65% of subjects were endurance-trained men between the ages of 20 and 30, and only one study measured performance in a race setting.<\/p>\n

The next explosion comes from Tim Noakes, the Discovery Health<\/em> Chair of Exercise and Sport Science from the University of Capetown, in a commentary (Role of hydration in health and exercise<\/a>) that can succinctly be summarized as: If you get thirsty you should drink and that over-hydration is a much more common and dangerous risk to the athlete than is dehydration.<\/p>\n

Next up is an analysis of the science behind the GSK sport drink Lucozade\u2019s claims that it boosts performance (Forty years of sports performance research and little insight gained<\/a>). The authors\u2019 conclusion says it all:<\/p>\n

“From our analysis of the current evidence, we conclude that over prolonged periods carbohydrate ingestion can improve exercise performance, but consuming large amounts is not a good strategy particularly at low and moderate exercise intensities and in exercise lasting less than 90 minutes. There was no substantial evidence to suggest that liquid is any better than solid carbohydrate intake and there were no studies in children. Given the high sugar content and the propensity to dental erosions children should be discouraged from using sports drinks.”<\/em><\/p>\n

And there\u2019s still more!<\/p>\n

Authors explore the marketing of sport drinks through social media and user endorsements (Miracle pills and fireproof trainers: user endorsement in social media<\/a>). Not surprisingly, Big Food are savvy marketers, and Facebook and Twitter let them get away with making claims that even the EFSA would frown upon. Basically what companies do is try to encourage \u201cuser-generated content\u201d which in turn they can then claim they didn\u2019t actually write.<\/p>\n

With the seventh article comes mythbusting (Mythbusting sports and exercise products<\/a>). Among the busted myths:<\/p>\n