The cod-liver-oil provides the vitamin A referred to in the thread previous to yours.

The Amount of Glucosamine Produced by the Body May be Insufficient. Glucosamine is an amino sugar normally formed in humans from glucose. Glucosamine Sulphate is one of the biological chemicals that forms all the major cushioning ingredients of the joint fluids and surrounding tissues. It helps make the fluid thick and elastic. In certain cases of trauma to the tissues, the amount of Glucosamine normally produced by the body is insufficient.