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Four Websites List Quality Products and Companies
20 December 2002, links updated January 2007
by Wyn Snow, Managing Editor

Four organizations currently perform quality testing and inspections—of supplement products and/or manufacturing plants. Here are the quality seals you can expect to see on products, together with links to lists and/or databases on the corresponding websites.

ConsumerLab.com seal   NNFA GMP seal   NSF International seal   USP DSVP seal
ConsumerLab.com Natural Products Association NSF International
US Pharmacopoeia

What do these quality seals mean?

1. ConsumerLab.comConsumerLab.com seal

Independent product testing:
ConsumerLab examines the research literature to understand the chemical makeup of products that have been shown useful in clinical (i.e., human) research studies—and establishes standards of quality for that product. It then selects popular brands for testing against these standards, which include identity and potency, purity, bioavailability, and consistency. [Go to ConsumerLab home page.] ConsumerLab also has programs that test raw materials and screen supplements for substances banned by athletic organizations (in particular, the Olympics). For more information, see www.ConsumerLab.com. (One must be a subscriber to access the full lists of products that pass testing.)

2. Natural Products Association (NPA, formerly NNFA)NNFA GMP seal

Manufacturing plant inspections:
NNFA's GMP Certification Program inspects manufacturing plants of member companies to determine if they are complying with good manufacturing practices (GMPs) developed by NNFA in collaboration with several other industry trade organizations. These GMPs include standards for quality control/assurance, cleanliness, checking identity and potency of ingredients, and testing of final products for potency, purity and bioavailability. (NNFA's GMP standards are the same as those for NSF International.) [Go to the NNFA list of certified companies.]

3. NSF InternationalNSF International seal

Manufacturing plant inspections:
NSF International's International Standard for Dietary Supplements uses the same set of criteria for good manufacturing practices as NNFA. NSF International convened a committee of stakeholders—
including individuals from industry, government, and consumer groups—who vote on the criteria in the standard. Negative votes must be resolved before the standard is approved. As noted under NNFA above, these GMP standards cover quality control/assurance, cleanliness, checking identity and potency of ingredients, and testing of final products for potency, purity and bioavailability. While NNFA's GMP Certification Program is available only to NNFA members, any company can apply for certification by NSF International. [Go to the NSF International database of certified companies and products. For a full list, leave the product search and manufacturer boxes blank.]

4. U. S. Pharmacopoeia (USP)USP DSVP seal

Independent product testing and manufacturing plant inspections:
USP's Dietary Supplement Validation Program (DSVP) both tests final products and inspects the plants where products are manufactured. USP conducts an initial testing of products submitted to them by the company, perform a inspections of manufacturing facilities, practices, records, and quality control measures to ensure that they meet USP requirements, and then conduct random marketplace tests on products carrying the USP mark to ensure that they continue to meet USP's standards over time. Criteria are established by a committee of stakeholders from industry, government and consumer groups. Product testing criteria include identity, potency, purity, bioavailability, and GMPs. [Go to USP's information about validated products and companies.]

What do these criteria mean?

  1. Identity and potency: Does the product contain the ingredients and dosage strength listed on the label?

  2. Purity: Is the product free of specific contaminants it should not have?

  3. Bioavailability: Does the product dissolve adequately for use in the body?

  4. Consistency: Does each tablet or other unit of the product have the same identity, potency and purity?

  5. Good manufacturing practices (GMPs): Does the manufacturing facility follow high-quality standards for

  • NPA/NSFIn'tl: procedures for quality control/assurance, cleanliness, checking identity and potency of ingredients, and testing of final products for potency, purity and bioavailability?

  • USP: safe, sanitary and well-controlled procedures?


ConsumerLab website.

Natural Products Association (NPA, formerly NNFA) website.

NSF International website.

US Pharmacopoeia (USP) website.end-of-story




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