How to choose a supplement that is actually tested
Supplements are not approved by the FDA before they are sold. Here is how to tell which products have been independently checked.
By [AUTHOR NAME]Medically reviewed by [REVIEWER NAME, MD]Updated [6] min read
Key takeaways
The FDA does not review supplements for safety or effectiveness before they reach shelves.
Third-party certification checks that a product contains what the label says.
More is not always better; some nutrients have upper limits.
Supplements can interact with prescription medications.
How are supplements regulated?
In the U.S., supplement makers are responsible for making sure their products are safe and accurately labeled, but they do not need FDA approval before selling them. That puts more of the burden on you to look for signs of quality.
How do you know a supplement is tested?
Independent organizations test products for label accuracy and certain contaminants. Seals to look for include:
USP Verified
NSF Certified, including NSF Certified for Sport
Other programs that publish their testing standards
How much of a supplement should you take?
Compare the amounts on the label to recommended intakes and upper limits. Vitamins A and D and minerals like iron can build up and cause problems at high doses, especially if you take more than one product containing them.
Can supplements interact with medications?
Some supplements change how medications work. St. John’s wort can interact with many drugs, and vitamin K can affect blood thinners such as warfarin. Share your full supplement list with your clinician or pharmacist.
When to talk to a clinician
Check with a healthcare professional before starting a supplement if you are pregnant or nursing, take prescription medication or are managing a health condition.
Common questions
No. The FDA does not approve dietary supplements before they are sold. Manufacturers are responsible for safety and label accuracy.
Sources
U.S. Food and Drug Administration. Dietary supplements: information for consumers. [ADD LINK]
NIH Office of Dietary Supplements. Fact sheets for health professionals. [ADD LINK]
USP and NSF International. Dietary supplement verification programs. [ADD LINK]
This article is for informational purposes only and is not medical advice. Talk to a licensed clinician before starting, stopping or changing any treatment.
