Post by Joey Smith on May 14, 2007 1:57:24 GMT -5
What is Glucosamine?
Glucosamine supplements are derived from shellfish shells. Glucosamine occurs naturally in the body and is a building block for the creation of glycosaminoglycans, which in turn become proteglycans. Proteoglycans help to pull water into the joint, which lubricates it, and nourish the collagen, which is a major component of the cartilage of the joint. According to Richard Stenlake, “ Glucosamine’s mere presence acts as a stimulus to the cells that produce proteoglycans – in fact glucosamine is a key factor in determining how many proteoglycans are produced by the cells” (15).
What are the Claims of Glucosamine?
Many of the claims of glucosamine involve its proposed ability to protect against the symptoms of osteoarthritis. It is also claimed to have anti-inflammatory abilities that compare to NSAIDs (non steroidal anti-inflammatory drugs) like ibuprofen. They are also theorized to help repair injured tendons.
Are the Claims of Glucosamine Justified?
Results are conflicting. This may be due to the fact that the actual production of glucosamine is not regulated – impurities may exist. Or, one form of glucosamine (there are three main forms – glucosamine sulfate, glucosamine hydrochloride, and N-acetylglucosamine) may be more bioavailable or easier to use by the body than the others. Also, some studies have tested glucosamine by injection in comparison to oral methods. Probably the most significant source of information that we have today investigating the claims of glucosamine is the Cochrane review, which is a meta-analysis of about 20 studies and over 2750 patients. Essentially, the conclusion of this review is that studies that used the Rotta brand of glucosamine showed improvement in pain and joint function over placebo (fake pill). Studies that did not use the Rotta brand of glucosamine did not show superiority in pain and joint function over placebo (fake pill) (3). As of now, certain parts of Asia accept it as a treatment for osteoarthritis under the name “Viatril-S” by Rottapharm (16).
Are there Any Side Effects to Glucosamine?
There have been no statistically significant side affects that occur when taking glucosamine. The number of adverse reactions that occur were very similar to the amount that occurred when subjects also took the placebo. The Cochrane review as well as several other studies have reported glucosamine to be safe (1)(3)(4)(10)(11)(13). However, a very high percentage of these studies only tested glucosamine at a dosage of 1500mg per day. The effects of higher dosages are not well known. Also, the long-term effects of glucosamine are not well known.
According to supplementwatch.com, “Diabetics may want to exercise a degree of caution when using glucosamine supplements, as there have been several animal studies and one small human pilot study that have suggested an increase in blood sugar levels during regular glucosamine consumption (though most of the animal studies have used injections of glucosamine)” (17).
What is the Proper Dosage?
As stated before, many studies only used dosages of roughly 1500 mg per day. It is unknown if using a lower or higher dosage would cause similar, worse, or better effects of joint health. Many manufactuers have stated that a liquid form of glucosamine is more easily digested. This may make sense logically; however it has not been tested in any studies.
Glucosamine – The Different Forms
There are three major forms of glucosamine that have been tested. These forms are glucosamine sulfate, glucosamine hydrochloride, and N-acetylglucosamine. Glucosamine sulfate is the most common form that is found in supplements, and it is also the most common form that is tested. Glucosamine hydrochloride is also another form, but with less studies to back it up. However, one study compared the two major forms and found that glucosamine hydrochloride is just as safe and effective as glucosamine sulfate (1). N-acetylglucosamine is a lesser found form and has been tested mostly been tested by injection. One study found that injecting N-acetylglucosamine into the joints of rabbits reduced the degragation of cartilage and provided anti-inflammatory benefits (14).
References:
(1) Qiu, GX, et al. A multi-central, randomized, controlled clinical trial of glucosamine hydrochloride/sulfate in the treatment of knee osteoarthritis. Zhonghua Yi Xue Za Zhi. 2005 Nov;85(43):3067-70.
(2) Cibere, J, et al. Glucosamine sulfate and cartilage type II collagen degradation in patients with knee osteoarthritis: randomized discontinuation trial results employing biomarkers. J Rheumatol. 2005 May;32(5):896-902.
(3) Towheed, TE, et al. Glucosamine therapy for treating osteoarthritis. Cochrane Database Syst Rev. 2005 Apr 18;(2):CD002946.
(4) McAlidon, T, et al. Effectiveness of glucosamine for symptoms of knee osteoarthritis: results from an internet-based randomized double-blind controlled trial. Am J Med. 2004 Nov 1;117(9):643-9.
(5) Cibere J, et al. Randomized, double-blind, placebo-controlled glucosamine discontinuation trial in knee osteoarthritis. Arthritis Rheum. 2004 Oct 15;51(5):738-45.
(6) Grove, ML. A randomized, double blind, placebo controlled trial of a topical cream containing glucosamine sulfate, chondroitin sulfate, and camphor for osteoarthritis of the knee. J Rheumatol. 2004 Apr;31(4):826; author reply 826-7.
(7) Braham, R. The effect of glucosamine supplementation on people experiencing regular knee pain. Br J Sports Med. 2003 Feb;37(1):45-9; discussion 49.
(8) Pavelka, K, et al. Glucosamine sulfate use and delay of progression of knee osteoarthritis: a 3-year, randomized, placebo-controlled, double-blind study. Arch Intern Med. 2002 Oct 14;162(18):2113-23.
(9) Hughes, R, and Carr, A. A randomized, double-blind, placebo-controlled trial of glucosamine sulphate as an analgesic in osteoarthritis of the knee. Rheumatology (Oxford). 2002 Mar;41(3):279-84.
(10) Muller-Fassbender, H, et al. Glucosamine sulfate compared to ibuprofen in osteoarthritis of the knee. Osteoarthritis Cartilage. 1994 Mar;2(1):61-9.
(11) Noack, W, et al. Glucosamine sulfate in osteoarthritis of the knee. Osteoarthritis Cartilage. 1994 Mar;2(1):51-9.
(12) Rindone, JP, et al. Randomized, controlled trial of glucosamine for treating osteoarthritis of the knee. West J Med. 2000 Feb;172(2):91-4.
(13) Qiu, GX, et al. Efficacy and safety of glucosamine sulfate versus ibuprofen in patients with knee osteoarthritis. Arzneimittelforschung. 1998 May;48(5):469-74.
(14) Shikhman, AR, et al. Chondroprotective activity of N-acetylglucosamine in rabbits with experimental osteoarthritis. Ann Rheum Dis. 2005 Jan;64(1):89-94.
(15) Stenlake, Richard. "How Does Glucosamine and Chondroitin Work?"
(16) "Glucosamine." Wikipedia.
(17) "Glucosamine." Supplement Watch.
Glucosamine supplements are derived from shellfish shells. Glucosamine occurs naturally in the body and is a building block for the creation of glycosaminoglycans, which in turn become proteglycans. Proteoglycans help to pull water into the joint, which lubricates it, and nourish the collagen, which is a major component of the cartilage of the joint. According to Richard Stenlake, “ Glucosamine’s mere presence acts as a stimulus to the cells that produce proteoglycans – in fact glucosamine is a key factor in determining how many proteoglycans are produced by the cells” (15).
What are the Claims of Glucosamine?
Many of the claims of glucosamine involve its proposed ability to protect against the symptoms of osteoarthritis. It is also claimed to have anti-inflammatory abilities that compare to NSAIDs (non steroidal anti-inflammatory drugs) like ibuprofen. They are also theorized to help repair injured tendons.
Are the Claims of Glucosamine Justified?
Results are conflicting. This may be due to the fact that the actual production of glucosamine is not regulated – impurities may exist. Or, one form of glucosamine (there are three main forms – glucosamine sulfate, glucosamine hydrochloride, and N-acetylglucosamine) may be more bioavailable or easier to use by the body than the others. Also, some studies have tested glucosamine by injection in comparison to oral methods. Probably the most significant source of information that we have today investigating the claims of glucosamine is the Cochrane review, which is a meta-analysis of about 20 studies and over 2750 patients. Essentially, the conclusion of this review is that studies that used the Rotta brand of glucosamine showed improvement in pain and joint function over placebo (fake pill). Studies that did not use the Rotta brand of glucosamine did not show superiority in pain and joint function over placebo (fake pill) (3). As of now, certain parts of Asia accept it as a treatment for osteoarthritis under the name “Viatril-S” by Rottapharm (16).
Are there Any Side Effects to Glucosamine?
There have been no statistically significant side affects that occur when taking glucosamine. The number of adverse reactions that occur were very similar to the amount that occurred when subjects also took the placebo. The Cochrane review as well as several other studies have reported glucosamine to be safe (1)(3)(4)(10)(11)(13). However, a very high percentage of these studies only tested glucosamine at a dosage of 1500mg per day. The effects of higher dosages are not well known. Also, the long-term effects of glucosamine are not well known.
According to supplementwatch.com, “Diabetics may want to exercise a degree of caution when using glucosamine supplements, as there have been several animal studies and one small human pilot study that have suggested an increase in blood sugar levels during regular glucosamine consumption (though most of the animal studies have used injections of glucosamine)” (17).
What is the Proper Dosage?
As stated before, many studies only used dosages of roughly 1500 mg per day. It is unknown if using a lower or higher dosage would cause similar, worse, or better effects of joint health. Many manufactuers have stated that a liquid form of glucosamine is more easily digested. This may make sense logically; however it has not been tested in any studies.
Glucosamine – The Different Forms
There are three major forms of glucosamine that have been tested. These forms are glucosamine sulfate, glucosamine hydrochloride, and N-acetylglucosamine. Glucosamine sulfate is the most common form that is found in supplements, and it is also the most common form that is tested. Glucosamine hydrochloride is also another form, but with less studies to back it up. However, one study compared the two major forms and found that glucosamine hydrochloride is just as safe and effective as glucosamine sulfate (1). N-acetylglucosamine is a lesser found form and has been tested mostly been tested by injection. One study found that injecting N-acetylglucosamine into the joints of rabbits reduced the degragation of cartilage and provided anti-inflammatory benefits (14).
References:
(1) Qiu, GX, et al. A multi-central, randomized, controlled clinical trial of glucosamine hydrochloride/sulfate in the treatment of knee osteoarthritis. Zhonghua Yi Xue Za Zhi. 2005 Nov;85(43):3067-70.
(2) Cibere, J, et al. Glucosamine sulfate and cartilage type II collagen degradation in patients with knee osteoarthritis: randomized discontinuation trial results employing biomarkers. J Rheumatol. 2005 May;32(5):896-902.
(3) Towheed, TE, et al. Glucosamine therapy for treating osteoarthritis. Cochrane Database Syst Rev. 2005 Apr 18;(2):CD002946.
(4) McAlidon, T, et al. Effectiveness of glucosamine for symptoms of knee osteoarthritis: results from an internet-based randomized double-blind controlled trial. Am J Med. 2004 Nov 1;117(9):643-9.
(5) Cibere J, et al. Randomized, double-blind, placebo-controlled glucosamine discontinuation trial in knee osteoarthritis. Arthritis Rheum. 2004 Oct 15;51(5):738-45.
(6) Grove, ML. A randomized, double blind, placebo controlled trial of a topical cream containing glucosamine sulfate, chondroitin sulfate, and camphor for osteoarthritis of the knee. J Rheumatol. 2004 Apr;31(4):826; author reply 826-7.
(7) Braham, R. The effect of glucosamine supplementation on people experiencing regular knee pain. Br J Sports Med. 2003 Feb;37(1):45-9; discussion 49.
(8) Pavelka, K, et al. Glucosamine sulfate use and delay of progression of knee osteoarthritis: a 3-year, randomized, placebo-controlled, double-blind study. Arch Intern Med. 2002 Oct 14;162(18):2113-23.
(9) Hughes, R, and Carr, A. A randomized, double-blind, placebo-controlled trial of glucosamine sulphate as an analgesic in osteoarthritis of the knee. Rheumatology (Oxford). 2002 Mar;41(3):279-84.
(10) Muller-Fassbender, H, et al. Glucosamine sulfate compared to ibuprofen in osteoarthritis of the knee. Osteoarthritis Cartilage. 1994 Mar;2(1):61-9.
(11) Noack, W, et al. Glucosamine sulfate in osteoarthritis of the knee. Osteoarthritis Cartilage. 1994 Mar;2(1):51-9.
(12) Rindone, JP, et al. Randomized, controlled trial of glucosamine for treating osteoarthritis of the knee. West J Med. 2000 Feb;172(2):91-4.
(13) Qiu, GX, et al. Efficacy and safety of glucosamine sulfate versus ibuprofen in patients with knee osteoarthritis. Arzneimittelforschung. 1998 May;48(5):469-74.
(14) Shikhman, AR, et al. Chondroprotective activity of N-acetylglucosamine in rabbits with experimental osteoarthritis. Ann Rheum Dis. 2005 Jan;64(1):89-94.
(15) Stenlake, Richard. "How Does Glucosamine and Chondroitin Work?"
(16) "Glucosamine." Wikipedia.
(17) "Glucosamine." Supplement Watch.