Nearly half of all Americans over 60 develop osteoarthritis  and according to some studies, as many as 80% of Americans over 65 are afflicted with it. The percentage of osteoarthritis sufferers in Canada is even higher.

Despite the widespread notion that only those "over the hill" get osteoarthritis, it has been detected even in adolescents. Joints don't just wear out with age. Although osteoarthritis is more common in seniors, age is definitely only one of the causes.

Research now indicates that, in addition to age, several other factors contribute to the development of osteoarthritis: heredity, as well as joint damage done by injury or by chronic obesity.

Interestingly, regardless of the contributing factors, osteoarthritis results from weakening bone and joint metabolism.

An injury such as a fracture or torn cartilage may result in osteoarthritis later in life, and osteoarthritis may follow unusual or prolonged strain on a joint either in work or sport. People who constantly stress their joints are at particular risk of getting osteoarthritis — e.g., bus drivers, miners, and foundry workers — while long distance runners who are trained in avoiding and recovering from injury are not more likely to develop osteoarthritis.

Being overweight for a long period of time is also considered to speed up the process. Obviously, extra weight leads to increased stress on weight-bearing joints such as the knees, hips, and lower spine, and anecdotal evidence suggests that people who are overweight are also more likely to develop osteoarthritis in their fingers and hands.

While osteoarthritis may be more likely to develop in the chronically obese, the jury is still out with regard to the exact causal link.

Some forms of osteoarthritis do run in families, especially those that affect the small joints of fingers. But in general, heredity is not a major reason for osteoarthritis.

In some people, osteoarthritis may be triggered by another disease, for example, Paget's disease.

Although the main cause of osteoarthritis is known to be weakened bone, joint, and muscle metabolism, the precise causal mechanisms are still unknown. Research is continuing with regard to cells within cartilage that break down and contribute to osteoarthritis.

Osteoarthritis is not caused by bacteria or poisons in the blood, acids in the body, diet deficiencies or excesses, gland abnormalities, the weather, exercise or sudden shock — although some of these may influence the pain.

Normally, joints operate with such a low friction level that they don't wear out, unless they are injured or used excessively. When bone and joint metabolism slows down, even at a low friction level, the joint cartilage soon wears out.

Osteoarthritis probably begins most often with an abnormality of the cells that synthesize the components of cartilage, such as collagen (a tough, fibrous protein found in connective tissue) and proteoglycans (substances that render the cartilage's resilience).

Next, the cartilage may grow too much but eventually thins and develops cracks on the surface. Then, tiny cavities form in the marrow of the bone beneath the cartilage, weakening the bone.

Bone can overgrow at the edges of the joint, producing bone spurs (osteophytes), which can be seen and felt. These bone spurs may interfere with normal joint function, causing pain.

Ultimately, the smooth, slippery surface of the cartilage becomes rough and pitted, so that the joint can no longer move smoothly. The components of the joint can all fail in different ways.

It's not uncommon for people who have developed osteoarthritis to report symptoms of osteoporosis, bone spurs or fibromyalgia. In fact, many bone-and joint-related problems can be traced back to one common source: weakened bone and joint metabolism. With age, bone and joint metabolism slows down naturally, causing all sorts of problems with bones, joints, and muscles. EZorb is the only product that has successfully addressed all those problems at their source — by raising the level of bone, joint and muscle metabolism.