Consumer Reports tests popular joint supplements

September 6, 2013

Victoria Primavera likes to stay active.

When she started feeling achy, she began taking over-the-counter supplements - and she thinks they work.

"I still have pain in my joints, but it's not so bad since I've been taking the glucosamine chondroitin," said Primavera.

"Some research suggests that the combination of glucosamine and chondroitin might reduce pain in some people who have osteoarthritis in their knees, but the evidence is still inconclusive. However, we know that a lot of people are buying these supplements, so we wanted to see whether they're getting what they're paying for," said Jamie Koph, Consumer Reports.

Those who take any supplements, should first talk to a doctor, especially if they are taking a blood thinner or are allergic to shellfish.

Consumer Reports tested 16 popular glucosamine-chondroitin supplements, evaluating three different samples of each.

First the samples were tested to see if they contained the amount of glucosamine and chondroitin the label indicated.

They also tested for heavy metals, like mercury and lead.

"Our tests show that none of the supplements contained worrisome levels of lead or other toxic metals. And all of the products contained their labeled amounts of glucosamine," said Koph.

However one, Nature Made Triple Flex Triple Strength, averaged only 65 percent of the labeled amount of chondroitin. Six others averaged 79 to 87 percent.

Of the 16 tested, two did not dissolve sufficiently, meaning the ingredients might not be fully absorbed in the body. They were the Trigosamine Max Strength and 365 Everyday Value Extra Strength from Whole Foods.

However, nine did meet Consumer Reports' quality criteria. The least expensive - Kirkland Signature Clinical Strength tablets from Costco.

The maker of the Nature Made supplement returned our call and gave us a statement.

They strongly dispute the way the test was performed by Consumer Reports and they stand by their product.

Read their entire statement below:

Pharmavite LLC, the manufacturer of Nature Made® dietary supplements, disputes the Consumer Reports' chondroitin sulfate testing methodology used for its Nature Made TripleFlex Triple Strength product as featured in the publication's October issue , which review of glucosamine and chondroitin combination products. The recent challenge from Consumer Reports is about the amount of chondroitin sulfate in our products as compared to what is stated on the label; it is not about safety. Nature Made® TripleFlex Triple Strength products continue to be safe and effective products that are used by consumers every day. Pharmavite takes the Consumer Reports findings seriously and respects the publication's role in evaluating products for consumers. However, in this particular situation, we strongly dispute its testing methodology. Why? Consumer Reports didn't use a test methodology for measuring the chondroitin sulfate in the products that was peer-validated and officially accepted. To be validated a testing methodology, the method must be capable of providing reproducible results among multiple laboratories. The level of reproducibility has not been achieved with the test method used by Consumer Reports. Ironically although Consumer Reports recognizes USP as a credible standard setting organization and indeed used their test methodology for other tests on these products, it did not use UPS's official and validated chondroitin sulfate testing mythology.

In contrast, we test every batch of our TripleFlex products using the official, industry-recognized, USP-validated testing methodology. Independent test results using this methodology found that the products noted in this article all met the standard set by Consumer Reports for its quality rating. Had Consumer Reports used the USP testing methodology for our product, we would have been listed as a product that met all of the quality criteria. We believe that the Consumer Reports different testing methodology is producing results that are not representative of the levels of chondroitin sulfate in the Nature Made TripleFlex product formulation. Of note,, an independent testing organization similar to Consumer Reports, published tests results of our TripleFlex products in May 2012, which indicated that our products met label claim.

Our consumers are important to us. Therefore, we will continue to investigate the difference in the test methodologies to try to understand why the Consumer Reports results are such an outlier.

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