Many athletes believe they need dietary supplements to perform at their best, but this trust in supplements is undeserved. Dietary supplements are regulated in a post-market fashion, which means that no regulatory body approves the accuracy of the label or the safety of the contents before they are sold to consumers.
As such, it is known that any supplement an athlete chooses could contain dangerous, illegal or banned ingredients. There are often no warning signs that a product is unsafe, and many athletes have suffered health problems or positive drug tests and sanctions from using products that are incorrectly labeled or contaminated with dangerous ingredients, such as anabolic steroids, pharmaceuticals, or research drugs. Sometimes, risky or dangerous ingredients are even listed right on the label or identified by a confusing name.
If athletes choose to use supplements despite these known risks, USADA has always recommended that athletes use only dietary supplements that have been certified by a third-party program that tests for substances prohibited in sport.
USADA currently recognizes NSF Certified for Sport® as the program best suited for athletes to reduce the risk from supplements.
Using an NSF Certified for Sport® product significantly reduces, but does not necessarily eliminate, the chance of testing positive and being sanctioned. Under the rules, if an athlete tests positive and establishes the source as a contaminated NSF Certified for Sport® product, the athlete could get a much-reduced sanction, but there likely would still be a consequence.