DHT:T Ratio in Male Rugby Players

Dear Editor-in-Chief: I read with great interest the article on creatine monohydrate supplementation affecting dihydrotestosterone to testosterone ratios in rugby players. The authors are to be commended for attempting to determine the mechanism of action of creatine supplementation on potential muscle growth. However, there are a few questions that must be answered before their results can be considered. In their methods section, they do not mention the source of the supplement given or whether the supplement was independently tested before it was given to the subjects. If the latter was not done, then the results of the study are in serious doubt. Since the passage of the 1994 Dietary Supplement Health and Education Act, the dietary supplement industry has exploded worldwide with annual sales of $24 billion in the United States alone. It is estimated that ‘‘sports supplements’’ account for $2.5 billion of that total. In addition to an increase in the sales, there has been an increase in contamination of dietary supplements with a variety of compounds. This has included pharmaceuticals such as testosterone, benzodiazepines, powerful diuretics, and potent stimulants. Several studies have been conducted demonstrating this phenomenon, and supplement companies frequently obtain their raw materials from countries such as China where the manufacturing regulations are lax. Unfortunately, this adulteration is not confined to obvious products that claim to increase testosterone, but even innocuous products such as multivitamins have been found to contain androgenic substances. A recent study found that creatine contaminated with 0.00005% 19-norandrostenedione could result in a positive urine test for nandrolone. In my experience, there can be significant intralot variation and intrabottle variation. Lastly, consumer studies have demonstrated that dietary supplements frequently do not contain the amount of active ingredients listed on the labels. Owing to the above facts, it is imperative that any research study involving dietary supplements needs to have the materials independently verified before being used in a study. I would recommend that the Journal adopt a policy not to accept any supplement study without this type of verification. There are now several organizations in the United States that will conduct a thorough analysis of a company and their products and certify that they do not contain any prohibited substances. This policy would be similar to medical journals insisting on proper human subject committee approval as a condition for publication. The authors need to respond if this had in fact been conducted, otherwise the contamination with androgenic compounds could seriously skew the results. This is one possible explanation as to why other similar studies have not produced the same results as the current study. In addition, the authors do not list the time of day that the study was conducted. Many hormones, including testosterone, have variations throughout the day and unless the subjects were all tested at the same time of day, this could alter the results. The authors also need to declare the source of the supplement and any conflict of interest from a company providing the creatine and/or funding the study. It would also be helpful if the authors clarified their experimental design with respect to their use of a placebo. Typically, placebo refers to an inactive substance or preparation used as a control in an experiment or test to determine the effectiveness of a medicinal drug. I would argue that 50 grams of glucose is not inactive and certainly can affect exercise. If the authors more properly were using the glucose as a control for the creatine, then I would have expected them to use 25 g/d as a loading dose and for maintenance instead of a 50 g loading dose and 30g/d during maintenance. A rationale for this methodology would be welcome. Lastly, the authors use a curious phrase in their introduction in which they state that creatine is ‘‘a popular ergogenic and androgenic [sic] aid. ’’ An androgen is typically considered to be any substance that promotes male characteristics. I am not aware of any data demonstrating that creatine promotes the development of male secondary sexual characteristics. Answers to the above questions would be helpful in allowing the readers to properly assess this article.