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Product Review: MSM (Methylsulfonylmethane)
Background:
Methylsulfonylmethane (MSM), also known as dimethyl sulfone or DMSO2, is used as a dietary supplement primarily for treating pain associated with osteoarthritis. It has also been proposed as treatment for other conditions including rheumatoid arthritis, inflammation of the bladder wall (interstitial cystitis), snoring, muscle spasm, and as an anti-cancer agent. All of these uses, including those for arthritis, however, are based on limited research and have not been well established. Many additional claims are found on MSM products, including skin-softening and nail-strengthening, but are also not well supported with research.
MSM is a compound that occurs naturally in both plants and animals, although its biological role is not known. The mechanism by which MSM may work is also not well understood, although it is known to contribute sulfur to the body which can then be used to synthesize certain amino acids (building blocks for proteins) and it can act as an antioxidant. MSM is chemically related to DMSO (dimethyl sulfoxide) which itself had earlier been used in many of the same ways as MSM. Unlike MSM, however, DMSO is a chemical solvent. DMSO was found to cause a range of adverse reactions and is no longer approved as a supplement — it can only be used on a limited basis under medical supervision.
Neither the U.S. government nor any other agency is responsible for routinely testing MSM supplements or other dietary supplements for their contents or quality. ConsumerLab.com, as part of its mission to independently evaluate products that affect health, wellness, and nutrition, purchased many of the leading MSM products sold in the U.S. and tested them for their quality.
Testing & Results:
In February and March 2001, ConsumerLab.com purchased 17 different MSM dietary supplements (see How Products were Selected), several of which also contained other ingredients, such as glucosamine and/or chondroitin or vitamin C (see separate ConsumerLab.com Product Reviews for Glucosamine and Chondroitin and Vitamin C for more information about these ingredients).
These products were tested to determine whether they contained the amounts of MSM stated on the labels. Products were also tested for DMSO contamination. Although probably not a health risk in small amounts, DMSO in products indicates poor manufacturing (see Testing Method and Passing Score).
Of these 17 MSM products, two failed testing because they respectively contained only 85% and 88% of their labeled amounts of MSM (see Passing Score). One of the products that did not pass was also found to have a small amount (0.05% by weight) of DMSO. All of the other products had less than this amount of DMSO or no detectable DMSO at all.
Listed below, alphabetically by name, are the products that passed ConsumerLab.com's independent testing of MSM supplements. (Note: Some of these products may also be listed among those passing ConsumerLab.com's Glucosamine and Chondroitin Product Review. Any MSM combination product that failed to pass another ConsumerLab.com Product Review was not eligible for evaluation in the MSM Product Review.) To further assist consumers, ConsumerLab.com is licensing its flask-shaped CL Seal of Approved Quality for MSM (see The CL Seal) to manufacturers for use on labels of products that have passed its testing. ConsumerLab.com will periodically re-evaluate these products to ensure their compliance with ConsumerLab.com's standards.
Examples of some of the products that passed ConsumerLab.com's independent testing of MSM dietary supplements are shown below:
EXAMPLES* OF CONSUMERLAB.COM APPROVED QUALITY
MSM SUPPLEMENTS
The complete list of Approved Products for this review now contains 16 products (including those tested after the initial posting) and is available to subscribers. Click on for additional information on the product To find retailers that sell some of the listed products click here.
Product
Name, Declared Amount of MSM Per Pill, and Pill Type
Manufacturer or Distributor
Maximum Strength Flex-A-Min® Glucosamine Chondroitin MSM (167 mg per tablet)
Mfd. By Arthritis Research Corp.
Nature's Bounty Maximum Strength Glucosamine MSM Complex (333 mg per tablet)
**Tested through ConsumerLab.com's Ad Hoc Testing Program after completion and posting of this review.
Unless otherwise noted, information about the products listed above is based on the samples purchased by ConsumerLab.com for this Product Review. Manufacturers may change product ingredients and information at any time, so be sure to check labels carefully when evaluating the products you use or buy. If a product's ingredients differ from what is listed above, it may not necessarily be of the same quality as what was tested. It also cannot be assumed that other products from a manufacturer or distributor listed above are of equal quality to those listed.
Copyright ConsumerLab.com, LLC, 2001. All rights reserved. Not to be reproduced, excerpted, linked to, or cited in any fashion without the express written permission of ConsumerLab.com LLC.
*The examples shown represent products whose manufacturers/distributors participated in ConsumerLab.com's testing and/or licensing programs for this Product Review.
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