Cartilage from the glucosamine-treated patients looked like it was from young, healthy people. Glucosamine is easily and rapidly absorbed by the body. Clinical trials have demonstrated improved joint function and mobility, reduced pain and inflammation and an actual reversal of joint degeneration as detected by radiographs. In addition to these improvements, another surprise benefit has been observed. Since chondroitin is a very large molecule, some authorities claim that it cannot be absorbed and is of no value as a supplement.
Pain relief is seen with continued use as damaged tissues are repaired and rebuilt.
In the comparison study with glucosamine and ibuprofen, it took 8 weeks for the glucosamine group to show less pain and more mobility than the ibuprofen group. That doesn't happen with pain relief medications. It may be possible to avoid, or at least postpone, joint degeneration indefinitely by taking these natural supplements prophylactically. It is definitely important to begin supplementation at the first sign of injury or degeneration. If the disease is allowed to progress until no cartilage remains, there is nothing left to repair.