Product Review:Glucosamine, Chondroitin, and MSM Supplements for Joint Health
HOW PRODUCTS WERE EVALUATED:
How Products were Selected:
Products were selected to represent those commonly sold and/or available nationally in the U.S. and Canada. ConsumerLab.com purchased products on the open market through retail stores, on-line retailers, and direct sales or multi-level marketing companies. Products were not accepted directly from manufacturers.
Testing Method:
Products containing glucosamine or chondroitin were first analyzed by High Performance Liquid Chromatography (HPLC), with chondroitin-containing products enzymatically digested prior to analysis. Products that did not pass this initial test were re-analyzed in another independent laboratory using a HPLC method or capillary electrophoresis (CE) (for chondroitin).
Products containing MSM were tested for their claimed amount of MSM and for DMSO. Analysis for MSM and DMSO was performed using a Gas Chromatography (GC) method. Products not having passing levels of MSM or DMSO were then re-tested in a second independent laboratory using a comparable GC method.
Disintegration of non-chewable, non-capsule, non-enteric coated and non-time release formulations was analyzed by ConsumerLab.com utilizing USP (United States Pharmacopeia) <2040> methodology.
Analyses for lead were performed using ICP-MS (Inductively Coupled Plasma-Mass Spectroscopy).
Products failing to meet any Passing Score were re-tested in a second independent laboratory using similar methods and instrumentation.
ConsumerLab.com may modify or use other appropriate test methods if necessary to test special product formulations.
Passing Score: *
To pass testing, a product must meet the following criteria:
All Products Tested:
Meet recommended USP parameters for disintegration for vitamin-mineral supplements (excluding capsule, enteric coated, chewable and time-release products).
Not exceed California Prop 65 levels for lead contamination in a recommended daily serving of a dietary supplement, i.e., contain less than 0.5 mcg of lead per daily serving with an additional allowance of 1.0 mcg for supplements containing 1,000 mg/day or more of elemental calcium and 0.5 mcg for supplements containing specific other minerals.** For supplements not marketed for use by children, ConsumerLab.com provides an additional allowance of 0.5 mcg if containing 250 to 499 mg/day of elemental calcium, or 1.0 mcg if containing 500 to 999 mg/day of elemental calcium, and an allowance of 0.5 mcg if containing one whole herb (not extract) ingredient or 1.0 mcg for two or more whole herb ingredients. If a maximum recommended daily serving is not defined, a daily serving size will be determined and applied by CL.
Glucosamine:
Contain at least 100%, and not more than 150%, of claimed amount of the appropriate claimed form(s) of glucosamine.
Chondroitin:
Contain at least 100%, and not more than 150%, of claimed amount of total chondroitin.
MSM:
Contain at least 100%, and not more than 125%, of claimed amount of MSM and less than 0.05% DMSO (%wt/wt).
A product passed if it passed each applicable criterion in any one of the analyses.
* Passing scores allow for specific margins of technical error associated with each analysis. ConsumerLab.com reserves the right to disqualify a product at any time from passing its testing if it considers such product to present a safety risk or to provide misleading or inaccurate information in its labeling.
** Based on State of California's Prop 65 lead limit. California requires supplements exceeding this limit to bear a warning label regarding lead.
