Diet & Fitness

Glucosamine sulfate (GS), a nutrient derived from seashells, is a building block needed for the synthesis and repair of joint cartilage. GS supplementation has significantly reduced symptoms of osteoarthritis in uncontrolled^6,7 and single-blind trials.^8,9 Many double-blind trials have also reported efficacy.^{10,11,12,13,14,15} One published trial has reported no effect of GS on osteoarthritis symptoms,¹⁶ and GS has been found to be ineffective for low back pain related to lumbar spine osteoarthritis.¹⁷ While most research trials use 500 mg GS taken three times per day, results of a three-year, double-blind trial indicate that 1,500 mg taken once per day produces significant reduction of symptoms and halts degenerative changes seen by x-ray examination.¹⁸ GS does not cure people with osteoarthritis, and they may need to take the supplement for the rest of their lives in order to maintain benefits. Fortunately, GS appears to be virtually free of side effects, even after three or more years of supplementation. Benefits from GS generally become evident after three to eight weeks of treatment.

In a preliminary trial, supplementation with glucosamine hydrochloride (1,500 mg per day) for 12 weeks produced a small but statistically significant improvement of pain in people with rheumatoid arthritis. However, other measures of disease activity, such as the number of swollen and painful joints did not improve.¹⁹

Glucosamine sulfate and chondroitin sulfate may both play a role in wound healing by providing the raw material needed by the body to manufacture molecules called glycosaminoglycans found in skin, tendons, ligaments, and joints.²⁰ Test tube and animal studies have found that these substances, and others like them, can promote improved tissue healing.^21,22,23,24 Injectable forms of chondroitin sulfate have been used in Europe for various types of sports-related injuries to tendons and joints,^25,26,27,28 and one preliminary trial reported reduced pain and good healing in young athletes with chondromalacia patella (cartilage softening in the knee) who were given 750–1,500 mg per day of oral glucosamine sulfate.²⁹ However, specific human trials of glucosamine and chondroitin sulfate for healing sprains and strains are lacking.

 

Some autistic children suffer from chronic diarrhea. In a study of children with autistic spectrum disorders and persistent diarrhea for many years, supplementing with 500 mg of glucosamine per day (spread over the morning and evening meal) for 30 days eliminated the diarrhea in five of six cases.³⁰ The authors hypothesized that glucosamine worked by blocking the effect of certain dietary components on the intestinal tract.

 

Some autistic children suffer from chronic diarrhea. In a study of children with autistic spectrum disorders and persistent diarrhea for many years, supplementing with 500 mg of glucosamine per day (spread over the morning and evening meal) for 30 days eliminated the diarrhea in five of six cases.³¹ The authors hypothesized that glucosamine worked by blocking the effect of certain dietary components on the intestinal tract.

 

One doctor has observed that supplementation with glucosamine sulfate (amount not specified) can increase the growth rate and strength of fingernails and toenails;³²however, no controlled trials have been done.