Supplements

Glucosamine

Glucosamine is one of a number of substances classified as an amino sugar. Unlike other forms of sugar in the body, amino sugars are components of carbohydrates that are incorporated into the structure of body tissues, rather than being used as a source of energy.

Glucosamine is involved in the formation of the nails, tendons, skin, eyes, bones, ligaments, and heart valves. It also plays a role in the mucous secretions of the digestive, respiratory, and urinary tracts.

Glucosamine is made from chitin, a component of shellfish. Although it is not extracted from the protein component of shellfish, individuals with shellfish allergies may want to check with a health care professional before taking glucosamine.

Glucosamine sulfate is considered by complementary doctors to be the treatment of choice for osteoarthritis. Glucosamine provides the building blocks for new cartilage, the protective joint padding that prevents bones from scraping against each other as we move. This cartilage wears away by this common form of degenerative arthritis.

Recent research indicates that glucosamine may also help slow the progression of osteoarthritis. In a controlled study, orally administered glucosamine sulfate was shown to prevent "joint space narrowing" and improve symptoms in subjects with knee osteoarthritis. Joint space narrowing is a measure of the loss of joint space due to articular cartilage breakdown.

Glucosamine may stimulate synovial production of hyaluronic acid (HA), a compound responsible for the lubricating and shock-absorbing properties of synovial fluid. HA has anti-inflammatory and analgesic properties, and its concentration is diminished in osteoarthritis.

A number of double-blind studies have demonstrated that oral glucosamine is at least as effective as NSAIDs (nonsteroidal anti-inflammatory drugs) for decreasing pain and improving mobility in osteoarthritis. Glucosamine is not as potent an anti-inflammatory agent as NSAIDs, but it is much less toxic to the gastrointestinal tract. Though NSAIDs can be used for temporary relief, habitual use is ruinous, for these drugs kill more than the pain. Every year about twenty-thousand people die from using NSAIDS.

According to head-to-head research comparisons, taking glucosamine supplements (which appear to trigger the joints' own production of the nutrient) will dampen osteoarthritic pain and increase joint mobility better than taking pharmaceutical pain relievers.

Glucosamine's relief and rejuvenation are not immediate. It may take up to six months for some people to notice improvement, others notice improvement in just a few weeks.

In an eight-week study that pitted glucosamine against ibuprofen, participants reported that they initially felt greater relief with ibuprofen. But by the end of the experiment the glucosamine users felt far better. Cell samples from their joints offered visible proof: the degenerating joints were in fact healing-something never before observed in ibuprofen users.

Deficiency: Osteoarthritis

Depleting Agents: Antibiotics, antiseizure medications, chemotherapy, x-rays, frozen foods, aspirin, air pollution, and mineral oil.

Sources: Chitin from shellfish

• Glucosamine sulfate: 500, 750, and 1,000 mg capsules and tablets
• N-acetyl glucosamine: 500 and 750 mg capsules and tablets
• Glucosamine hydrochloride (HCL): 500, 750, and 1,000 mg capsules and tablets
• Glucosamine/chondroitin sulfate combination products

Most studies have been done on glucosamine sulfate. There is debate as to whether the glucosamine HCL form is effective. Chondroitin sulfate has been shown to be more effective than placebo on osteoarthritis of the knee and hip, but debate exists as to how well it is absorbed by the body. More study is needed on these glucosamine combinations and preparations.

Precautions: The majority of studies indicate that glucosamine is safe, nontoxic, and causes only minor side effects, which include mild gas, diarrhea, and bloating.

Glucosamine sulfate may contain high amounts of sodium or potassium. Individuals on a salt- or potassium-restricted diet, or taking potassium-sparing diuretics, should check labels before taking glucosamine sulfate.

Animal studies suggest that glucosamine may raise insulin resistance. Diabetics should have their blood sugar checked regularly.

Glucosamine is made from chitin-a component of shellfish. Although it is not extracted from the protein component of shellfish, individuals with shellfish allergies may want to check with a health care professional before taking glucosamine.

Dosage Ranges and Duration of Administration: Recommended dosage is 1,500 mg glucosamine per day (500 mg, tid) for one to two months. Ongoing supplementation may be required to prevent progression of osteoarthritis and to reduce pain and inflammation.

As a preventative taking 500 mg twice daily may delay the onset of osteoarthritis.

INTERACTIONS

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)
The combination of glucosamine and NSAIDs may reduce the doses needed for anti-inflammatory activity as well as the side effects associated with these drugs (Zupanets et al. 1991). In an in vitro study, lower doses of diclofenac, indomethacin and piroxicam combined with glucosamine reduced experimentally-induced inflammation in mice.