Osteoarthritis is a type of arthritis that is caused by the breakdown and eventual loss of the cartilage of one or more joints. Cartilage is a protein substance that serves as a "cushion" between the bones of the joints. Osteoarthritis is also known as degenerative arthritis. Among the over 100 different types of arthritis conditions, osteoarthritis is the most common, affecting over 20 million people in the United States.

Osteoarthritis occurs more frequently as we age. Before age 45, osteoarthritis occurs more frequently in males. After age 55, it occurs more frequently in females. In the United States, all races appear equally affected. A higher incidence of osteoarthritis exists in the Japanese population, while South African blacks, East Indians and Southern Chinese have lower rates.

Osteoarthritis commonly affects the hands, feet, spine, and large weight-bearing joints, such as the hips and knees. Most cases of osteoarthritis have no known cause and are referred to as primary osteoarthritis. When the cause of the osteoarthritis is known, the condition is referred to as secondary osteoarthritis.

Recently, the food supplements glucosamine and chondroitin have been shown to relieve symptoms of pain and stiffness for some persons with osteoarthritis. These supplements are available in pharmacies and health food stores without a prescription, although there is no certainty about the purity of the products or the dose of the active ingredients because they are not monitored by the FDA.

The National Institutes of Health is studying glucosamine and chondroitin in the treatment of osteoarthritis and this research will clarify many issues regarding dosing, safety, and effectiveness of these products for osteoarthritis. Patients taking bloodthinners should be careful taking chondroitin as it can increase the blood thinning and cause excessive bleeding. Fish oil supplements have been shown to have some anti-inflammation properties and increasing the dietary fish intake and/or fish oil capsules (omega-3 capsules) can sometimes reduce inflammation of arthritis.
(http://www.medicinenet.com/osteoarthritis/page5.htm)