Supplement Labels and the NSF-Certified Seal

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If you want to be 100 percent certain that your supps are clean, look for NSF-certified products.

NSF International is an independent, third-party organization that is paid by companies to test their dietary supplements intensely to ensure substances such as steroids, narcotics, stimulants and diuretics are not included.

Believe it or not, even if you read a dietary supplement label thoroughly, what you see is not necessarily what you get. Ed Wyszumiala, general manager of Dietary Supplements Certification programs for NSF International, says, "Some nutritional supplements may contain unlisted or banned substances."

Poor manufacturing practices, which can lead to cross-contamination and therefore trace levels of banned substances, is one cause. Another? According to Wyszumiala, some manufacturers intentionally add unlisted ingredients or stimulants. "Products such as these are illegally being sold as dietary supplements," he says.

These unlawful products can be dangerous. Besides getting you booted from competition, banned substances can result in serious adverse side effects, including restlessness, anxiety, irregular heartbeat and others that are potentially lifethreatening. Three particularly dangerous ingredients, according to Wyszumiala, are caffeine, ephedra and synephrine. In total, the NSF tests for 142 banned analytes and reviews label claims.

Bottom line: the NSF can verify a product's contents. And when a product is given the NSF mark, "the product has been rigorously tested in accredited laboratories," Wyszumiala says. Furthermore, you are guaranteed that the product's only ingredients accordare listed on the label, no unacceptable levels of contaminants are present and the product has been okayed by the NCAA, MLB and NFL.

Visit for more information about supplement quality. For a list of NSFCertified sports supplements, go to

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