Suppression of information on the prevalence and prevention of exercise-associated hyponatraemia

It has been suggested recently that financial links between manufacturers of sports drinks and professional Sports Science organisations in North America have suppressed information on the existence and ways of preventing an epidemic of exercise-associated hyponatraemia (EAH). This article reviews evidence for the prevalence of both biochemical and clinical hyponatraemia. It concludes that a limited number of cases of EAH occur after ultra-long distance events, particularly when performed under cold and wet conditions, and that some eight deaths have been associated with EAH since 1985. However, this information has been widely reported, both in North America and in other parts of the world. Claims of an 'epidemic' seem unwarranted, and there is no solid evidence supporting the claim that information has been suppressed because of ties between sports scientists and sports drink manufacturers.