Short answer
Third-party tested supplements have been checked by an outside group, but what gets checked depends on the program. FDA does not approve supplements before they are sold. USP Verified checks ingredients, contaminants, dissolving and manufacturing. NSF Certified for Sport also screens for 290 banned substances. Informed Sport tests every batch for banned substances. A claim means little unless the product is in the program's own database.
What FDA does and does not do
Under the Dietary Supplement Health and Education Act of 1994, FDA is not authorized to approve dietary supplements for safety and effectiveness before they are marketed. In many cases, firms can sell a new supplement without even notifying FDA.
The companies themselves are responsible for checking the safety and labeling of their products before sale. FDA can act against an adulterated or mislabeled supplement after it reaches the market. That gap is what third-party programs try to fill, each in its own way.
What the main programs check
USP Verified: the product contains the listed ingredients in the declared strength and amounts, has no harmful levels of specified contaminants such as heavy metals and pesticides, follows FDA Good Manufacturing Practices, and breaks down in a set time.
NSF Certified for Sport: built on NSF/ANSI 173, NSF's dietary supplement standard. It verifies label contents, no unsafe contaminants, none of 290 banned substances, and a manufacturing facility that NSF audits on a set schedule.
Informed Sport tests every batch for banned substances before release. Informed Choice relies on monthly retail monitoring. Both focus on banned substances in sport.
How ConsumerLab differs
ConsumerLab is a private company that publishes its own test results. For its Product Reviews it buys products at retail itself and does not accept samples from manufacturers. Most of its revenue comes from paid memberships, so many results sit behind a subscription.
It also earns fees from its Quality Certification Program and from brands that license its seal after passing. A product carrying the seal must be retested every twelve months from a random sample bought on the open market. So the seal is a paid license that depends on passing ConsumerLab's tests.
How to check any brand yourself
Price does not tell you what is in the bottle. A seal tells you what was checked, but only for that specific product, and only once you confirm it with the certifier rather than the brand.
USP lists verified products in its Product Finder at quality-supplements.org. NSF lets you search Certified for Sport products by name or lot number at nsfsport.com or in its app. Informed Sport and Informed Choice let you search by brand, product name or batch number. If the product, flavor or lot is not listed, the claim on the label is unverified.
Related questions
Does FDA test supplements before they are sold?
No. FDA says it is not authorized to approve dietary supplements for safety and effectiveness before they are marketed. It can act against problem products after they are on the market.
Does a third-party seal mean a supplement works?
No. The criteria these programs publish cover contents, contaminants, banned substances and manufacturing, not whether the product helps you.
Is a cheaper brand lower quality?
Price alone does not answer that. Look the exact product up in the USP, NSF or Informed databases, or in ConsumerLab's results.
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Published 2026-10-07 · Last checked 2026-10-07
Educational content, not medical advice. Made for the United States.