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Can I trust lab reports provided by supplement manufacturers?


You need to be very skeptical of information provided by supplement manufacturers and sellers. Over the years, we have seen lab reports and certificates that do not accurately reflect the quality of the products sold. How could this be? Reasons include an incorrect or inferior ("forgiving") test; a test that was not performed correctly; results that are not based on the product in question but on a different product or formulation; or, results that are simply made up. Believe it or not, there have been instances where labs don't do any analyses but issue reports nonetheless (a practice known as dry labbing).

If you request or are shown a report, at a minimum, make sure it's from an independent, third-party laboratory and that it's a test of the specific product in question (preferably the same lot), using an appropriate test method. If you'd like to know the specific test methods and approval criteria used by, we make them freely available here.

Another question we often get is "Which labs does ConsumerLab use and recommend?" Due to the variety of analyses we employ to assess the potency, purity, and freshness of the products we review, we make use of many specialized outside laboratories. Each is carefully vetted by our scientific staff experienced in analytical chemistry, pharmacology, and toxicology.

During our first few years of publishing product reviews, starting in 1999, we disclosed the names of some of the laboratories we used. However, we learned that manufacturers began pressuring these labs to not work with us. To help prevent this, we stopped identifying the labs we use.

Interestingly, just last month, in January 2018, two of the labs with which we have worked for many years informed us that they could no longer work with us due to "corporate policies" of the company that recently acquired both of them. When we pressed the labs about these "policies," the Director of Industry and Regulatory Affairs at Covance Food Solutions (the acquiring company) responded that, "The belief is that Covance has contracts with most of the companies" that make the products ConsumerLab evaluates and that "Testing out customers products for [sic] would be a conflict of interest for Covance." We were astounded by this. How could testing a product for ConsumerLab create a conflict of interest? Is there concern that the results might differ from the results produced for the manufacturer of the same product? Moreover, does Covance see itself as representing or, perhaps, defending manufacturers rather than simply providing objective analyses? This is both an unusual and disconcerting policy for an analytical laboratory, in our opinion.

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October 6, 2018

Is the acquisition by Eurofins going to change your relationship with their labs?
October 8, 2018

We have not yet been informed of any changes in the policies of those labs.

February 14, 2018

There can't be that many laboratories doing this sort of testing. Will Consumerlab be able to find new partners who are competent and trustworthy to do its testing? Perhaps at a university? (Although even they are being compromised by the corporate sector these days...)
February 17, 2018

Hi Jane - Thanks for your concern, but there are many other good laboratories with which we work, in addition to the testing we conduct in-house. This does not in any way compromise our ability to rigorously test products.

February 4, 2018

CL, thank you for this frank and revealing information about Covance Food Solutions!
Next I'm going to Search to learn which companies fall under their corporate umbrella.

February 4, 2018

I would very much like to pose your last question to Covance myself.

February 4, 2018

Yes, integrity is key. That is what we are paying for. Thank you.

February 4, 2018

their (covance food solutions) actions are very disappointing

February 4, 2018

I'm flabbergasted. To have companies actually fighting ConsumerLab because they are printing factual truths about the ingredients in products - some which might even be dangerous for some individuals - and admitting that it doesn't want customers to know what they are ingesting ..... how can they possibly get away with that?

February 4, 2018

Truly horrifying and this should be a matter of concern for everyone. I hope you contact media outlets about this development.

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