关于骨胶和维骨力(Glucosamine and Chondroitin Sulfate)的几个问题？

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Glucosamine and Chondroitin Sulfate
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2 o; M" Y* r& B' b0 \) I1 S) qWhat Are Glucosamine and Chondroitin Sulfate?
# B! J: A* s9 j8 HGlucosamine and chondroitin sulfate are substances found naturally in the body. Glucosamine is a form of amino sugar that is believed to play a role in cartilage formation and repair. Chondroitin sulfate is part of a large protein molecule (proteoglycan) that gives cartilage elasticity.
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4 ?  V9 F9 ~: cBoth glucosamine and chondroitin sulfate are sold as dietary or nutritional supplements. They are extracted from animal tissue: glucosamine from crab, lobster or shrimp shells; and chondroitin sulfate from animal cartilage. Chondroitin sulfate is most often extracted from the cartilage of cattle tracheas, but it is also extracted from shark cartilage.
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What Are Glucosamine and Chondroitin Sulfate Used For?
Glucosamine and chondroitin sulfate supplements have been used to treat osteoarthritis in horses and dogs for many years. In Europe, people have used glucosamine and chondroitin sulfate to treat osteoarthritis since the 1980s. These supplements have not yet been studied in the treatment of other forms of arthritis or related conditions, such as rheumatoid arthritis or gout, or in other causes of pain such as stress fractures.


What Do Glucosamine and Chondroitin Sulfate Do?
+ n! U2 }% v' D' S' BIn past studies done primarily in Europe, some people with mild to moderate osteoarthritis who took either glucosamine or chondroitin sulfate reported pain relief at a level similar to that of nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin and ibuprofen.
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Although some researchers speculate that the supplements may slow cartilage loss in people with osteoarthritis, there is no definitive evidence that such slowing occurs. Longer-term, double-blind, controlled scientific studies to assess the benefits and safety of the supplements currently are being conducted, including an in-depth clinical study by the National Institutes of Health.


What Do I Look For in Glucosamine and Chondroitin Sulfate?
) P6 o2 f- y6 P1 \Glucosamine comes in several forms called salts, usually either glucosamine sulfate or glucosamine hydrochloride. Both forms have been reported to work equally well, although most studies have been done with the sulfate form.

Experts recommend taking chondroitin sulfate in supplement form. Some shark cartilage products also contain chondroitin sulfate, although the quality and amount in these products are inconsistent.
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2 P. e+ S& Y. S- X& CBecause dietary supplements are unregulated, the quality and content may vary widely. If you decide to take these supplements, choose products sold by large, well-established companies that can be held accountable. Read the product labels carefully to make sure the ingredient lists make sense to you. If you have trouble, ask your pharmacist for help. Recommended doses should cost about $1 to $3 per day, but this cost is not covered by most insurance companies.
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Be sure to consult your doctor before deciding to try these supplements. Make sure that osteoarthritis is the cause of your pain. Do not stop or reduce your current prescribed medications without talking with your doctor.


, o0 d* y  r; e2 @How Do I Take Glucosamine and Chondroitin Sulfate?
Although some experts recommend taking glucosamine alone, others recommend only chondroitin sulfate, and some recommend both. Taking glucosamine and chondroitin sulfate together has not been shown to increase their individual effects.
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" @) B$ U- O! \9 ^% q  w1 F9 P& gIf you decide to take either or both of these supplements, experts recommend taking the amount that has been used in the studies. For glucosamine this amount is 1,500 milligrams (mg) per day; for chondroitin it is 1,200 mg per day.
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( y8 ~4 a6 ^" b4 lStart by taking the supplements along with your current medications for six to eight weeks. If you don’t experience any difference in your symptoms by then, you probably will not get any relief from using the supplements. Some people may get partial relief by using the supplements, but they may still have to take medications for full relief.
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If you have advanced osteoarthritis with a great deal of cartilage loss, glucosamine and chondroitin sulfate probably will not help you.
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% G& d, j& u6 t9 H1 h9 MWhat Are The Side Effects of Glucosamine and Chondroitin Sulfate?
The most common side effects of glucosamine and chondroitin sulfate are increased intestinal gas and softened stools. If you experience these problems, you may want to try another supplement brand before you stop using the supplements altogether.
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, ?, z+ Y% L  _' }( CMore studies need to be done to confirm the safety and effectiveness of glucosamine and chondroitin sulfate. Be sure to consult your doctor if you notice any unusual or new symptoms while you are taking these supplements.
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Keep in mind that unlike drugs, glucosamine and chondroitin sulfate are not regulated by the Food and Drug Administration. The quality and effectiveness of the products available in stores may vary widely.


Cautions
5 z: l" h6 s7 |" E) fAlthough not enough studies have been done on glucosamine and chondroitin sulfate to know all of the necessary precautions, the following groups of people should be especially careful when considering these supplements:
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Children, women who are pregnant, and women who could become pregnant should not take these supplements. These substances have not been studied long enough to determine their effects on a child or on a developing fetus.
: f0 m/ ~+ s: }Because glucosamine is an amino sugar, people who have diabetes should check their blood sugar levels more frequently if they take this supplement.
1 n/ x% L4 f  `. ^  g, zIf you are taking chondroitin sulfate in addition to a blood-thinning medication or daily aspirin therapy, have your blood clotting time checked more often. This supplement is similar in structure to the blood-thinning drug heparin, and the combination may cause bleeding in some people.
If you are allergic to shellfish, consult your doctor before deciding to take glucosamine. In most cases, however, allergies are caused by the proteins in shellfish, not by chitin, a carbohydrate from which glucosamine is extracted.