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To help consumers and healthcare professionals find the best quality health and nutrition products through independent testing and evaluation.

OVERVIEW:, LLC ("CL") is the leading provider of independent test results and information to help consumers and healthcare professionals identify the best quality health and nutrition products. It publishes results of its tests in comprehensive Product Review reports at for its members. CL also conducts an annual Survey of Vitamin & Supplement Users. CL's research is cited frequently by the media and in professional journals. In addition to the products it selects to review, CL enables companies of all sizes to have the quality of their products tested for potential certification as a CL Approved Quality product and to bear the CL Seal. Since its founding in 1999, CL has tested more than 7,000 products, representing over 1,000 different brands and nearly every type of popular supplement for adults, children, and pets as well as healthy foods and beverages and health protection devices.


Types of Products Tested:

CL evaluates consumer products relating to health, wellness, and nutrition, including:

  • Health & Nutrition Products:
    • Herbal Products
    • Vitamins
    • Minerals
    • Other Supplements
  • Sports & Energy Products
  • Healthy Foods & Beverages
  • Health Protection Devices

From time to time, CL may evaluate additional types of products that impact consumer health, wellness, or nutrition.

How Products Are Tested: has perhaps the highest testing standards of any third party group certifying the quality of dietary supplements. is also the only third-party verification group that freely publishes its testing methods and quality criteria/standards. These can be found at How Products Were Tested.

Products are tested, whenever possible, for each of the following:

  • Identity: Does the product meet recognized standards of identity and does the product meet the level of quality claimed on the label?
  • Strength (quantity): Does the product contain the amount of ingredient claimed on the label?
  • Purity: Is the product free of specified contaminants?
  • Disintegration: Does the product break apart properly so that it may be used by the body? [See Home Test for Disintegration for how to test your supplements]

These quality criteria must be met to be considered Approved by CL. If a manufacturer seeks to use the CL Seal of Approval on the product, the product must be tested for these criteria every twelve months based on a random sample purchased on the open market.

Quality Criteria / Standards:

The FDA's Good Manufacturing Practices (GMPs) for dietary supplements allow each manufacturer to determine the quality standards and analytical methods it uses to evaluate the quality of its products. Some choose to use less specific standards and/or lenient test methods that can make a low quality product appear to be high quality. We see no reason why consumers should accept low quality ingredients or unnecessarily expose themselves to avoidable contaminants. We adopt the most meaningful and strict standards based on the latest international research and recommendations.

For example, the amount of lead contamination that some U.S. companies and other third-party testing groups permit in supplements can be as much as forty times higher than what would permit and what is allowed in the State of California without a warning label. Our standards can be found at How Products Were Tested.

Testing Methods:

CL seeks to use the most accurate and appropriate test methods for each ingredient. Each Product Review provides a link to the methods used. Below are examples of analytical equipment employed:

  • CE (capillary electrophoresis)
  • Gas chromatography with detection by FID (flame ionization detector), ECD (electron capture detector) and MS (mass spectroscopy) or MS/MS (tandem mass spectroscopy)
  • HPLC (high performance liquid chromatography) in conjunction with a variety of detection methods including IR (infra-red), photodiode array, ELSD (evaporative light scatter detector), MS (mass spectroscopy), and MS/MS (tandem mass spectroscopy)
  • HP-TLC (high performance thin-layer chromatography)
  • ICP/MS (inductively coupled plasma/mass spectroscopy)
  • Microscopy
  • MS (mass spectroscopy)


Due to the range of testing methods needed to thoroughly evaluate products, tests other than initial disintegration analysis (which is performed by CL) are performed at nationally and internationally recognized independent laboratories. These labs are qualified and selected by CL based on their expertise for specific types of testing. CL's expert research staff closely evaluates the performance and work of these laboratories. This may include sending additional blinded samples (e.g., duplicates, "blanks", and well-characterized reference materials) within a group of test samples to monitor method performance.

These facilities carry various federal (FDA, EPA, USDA, DEA) and state licenses and accreditations, follow peer reviewed validated methods published by authoritative institutions such as USP (United States Pharmacopea) and AOAC (Association of Analytical Communities) International, and follow guidelines based on GLP (Good Laboratory Practice) protocols. Many of these laboratories have additional accreditations by independent outside groups (e.g., ISO and A2LA), participate in method validation programs, and undergo regular proficiency testing evaluations to further demonstrate their analytical capabilities.

To eliminate potential bias, the identities of product samples and their claimed ingredients are not disclosed to the testing laboratories.

Testing Programs:

Products are tested through CL's Product Reviews and its Quality Certification Program (previously known as the Voluntary Certification Program).

Product Reviews:

Product Reviews are CL's independent tests of multiple brands of products claiming to have the same key ingredient. Product Reviews have the following features:

  • Exclusively directed by CL.
  • Products tested are purchased independently by CL at the retail level (stores, mail order, online, etc.). CL does not accept product samples from manufacturers for Product Reviews and CL may select samples at any time during the year (to avoid sampling bias).
  • Products are selected by CL to reflect popular brands in the market as well as a selection of smaller brands. Results of CL's Annual Survey help guide product selection.
  • Any product not passing CL's quality criteria is re-tested for confirmation in a second independent laboratory using similar methods and instrumentation.
  • After a Product Review is completed, results for products selected for testing by CL are available online to subscribers. Products that have passed the Quality Certification Program are also listed in respective Product Reviews.
  • Brands that "Pass" may carry the CL Seal of Approval upon acceptance by the manufacturer of the CL Seal Use License Agreement (described below).
  • Product Reviews are repeated periodically (approximately every 24 to 36 months) for each product category. However, CL may re-test brands at any time. A change in a brand's test results will be reflected in CL's website and will affect eligibility for the CL certification seal. When a newer Product Review is posted, it replaces any previous Product Review covering the same category of products and the older review is removed from the website. Product selection typically changes from review to review in order to sample currently marketed products and their most current formulations. At any given time, reviews of over 1,400 products are available on the CL website.
  • Full reports of Product Reviews are available in Product Review Technical Reports sold by CL.
Policy Toward Manufacturers and Distributors of Products that Fail to Pass CL Testing:

Manufacturers and distributors of products that fail to pass CL's testing may request a summary of CL's test results, product lot number, expiration date, and place and date of purchase for such product. This information is provided by CL at no cost within three business days of receipt of written request.

CL maintains, for up to two years, reserve samples of all products that it tests. If a manufacturer/distributor of a tested product disputes CL's findings with evidence supporting an error by CL, CL will offer reserve sample (if not expired) for repeat testing by a third-party laboratory of mutual acceptance to the manufacturer/distributor and CL using a mutually acceptable test method. The manufacturer/distributor will directly pay the selected laboratory. There is no charge by CL for providing and shipping the sample. Prior to re-testing, the manufacturer/distributor must agree that it will publicly announce results of the re-testing on its main website on a page accessible through not more than a single link from its homepage. CL will similarly publish the findings on its website.

Quality Certification Program:

See details about CL's Quality Certification Program here.


Brands that "Pass" Product Reviews, or the Quality Certification Program are posted on CL's website as having "Passed" the specific test performed. Manufacturers of brands that "Pass" may purchase a license to use the CL Seal of Approval on their product labels, packaging, promotion, and advertising according to parameters set forth in the CL Seal Use License Agreement. Such licenses expire upon established dates and automatically terminate if the product does not "Pass" any re-testing by CL. In order to continue to carry the CL Seal directly on product labeling, the product must pass retesting every twelve months.

OWNERSHIP, AFFILIATIONS, AND SOURCES OF REVENUE:, LLC is a privately held company based in New York. It is not affiliated with manufacturers of health and nutrition products. Revenues are derived primarily from online membership fees that fund ConsumerLab's extensive product testing and research, report writing and editing, and website infrastructure to publish its Product Reviews, CL Answers, Recalls and Warnings, and Newsletter. Revenues are also derived from Quality Certification Program fees, authorized use of the CL Seal of Approval, and sales of survey reports. To help readers check the latest prices on products tested and Approved for quality in our reviews, we permit vendors that we have found to be reputable to have PriceCheck links to webpages on their sites where these specific products are sold. We receive no revenue from sales of products that occur from use of these links but do receive a click fee when a link is used. We have not necessarily tested nor Approved other products on a vendor's site. Articles that focus on avoiding counterfeit online vendors may contain affiliate links to vendors authorized to sell a particular brand of products. Those affiliate links may generate a commission paid to if a product is purchased from the linked site. Affiliate links do not appear in Product Reviews on, as CL does not otherwise derive revenue from the sale of products that it reviews.


CL welcomes input from any interested party (e.g., consumer groups, retailers, healthcare professionals, academic and commercial researchers, manufacturers, government agencies, trade groups, etc.) in its testing policies and procedures. Comments and questions should be submitted electronically to