Q: Enjoyed your columns on glucosamine and joint repair for osteoarthritis. What is the purpose of the MSM contained in some glucosamine/chondroitin products?
A: MSM (methylsulfonylmethane), like glucosamine and chondroitin, is a naturally occurring compound normally found in the body. MSM supplements, among other things, are promoted to reduce arthritis pain and degenerative changes associated with arthritis, but there's little meaningful research to back up these uses.
Q: Would you recommend using "Move Free" to ease my severe joint pain until I can see my physician next month?
A: The Move Free product you refer to contains MSM (discussed above) in addition to the glucosamine/chondroitin combination. It typically takes a few weeks for these supplements to exert their effects, so you might need conventional pain medication during this interim period.
Q: I have been taking a liquid glucosamine product called Syn-Flex for my joint pain. After reading your column warning that some of these products might contain too much manganese, I checked the label and saw that it lists manganese 5 mg. Is this too much? I also take a Centrex Silver pill each day that also contains manganese.
A: My caution was that some glucosamine/chondroitin products provide excessive levels of the mineral manganese when taken at the recommended number of doses a day. The established safe upper limit for manganese in adults is 11 mg daily. Getting more than that for prolonged periods could increase the risk of adverse neurologic effects.
I believe that the Syn-Flex liquid you take is designed to be taken in a once daily dose that provides 5 mg of manganese, a safe amount. Check the product label to make sure this is correct. If the Centrex Silver you refer to is a store brand of Centrum Silver, it contains 2 mg of manganese, so that adds up to 7 mg of manganese daily. You're also getting manganese from the diet.
The adult recommended daily intake for manganese is 1.8 mg in women and 2.3 mg in men, similar to amounts consumed in the diet, though vegetarians tend to get much more.
It you eat a typical diet, your manganese intake is probably in the safe zone.
By the way, both Move Free (Schiff) and Syn-Flex (Activex) passed independent certification testing by ConsumerLab.com. This means that the products contain what the label promises, an important consideration in the loosely regulated dietary supplements marketplace.
Q: My husband takes a Sam's Club brand of glucosamine and chondroitin. It does not list manganese in the "supplement facts" section. Does this mean that the product does not contain manganese?
A: That's right. If a product contains manganese, it is required to be listed on the label.
(Richard Harkness is a consultant pharmacist who writes on health care topics. You can write him at 1224 King Henry Drive, Ocean Springs, MS 39564. His e-mail address is firstname.lastname@example.org. Volume of mail prohibits individual replies; selected letters will be answered in his column.)
(c) 2003, The Sun Herald (Biloxi, Miss.). Distributed by Knight Ridder/Tribune News Service.