Osteoporosis

Osteoporosis means porous bones. Bones affected by osteoporosis are less dense than normal bones and are more likely to break, even as a result of a minor bump or fall, or even without an injury. It is around four times more common in women than men, and most common in women who have been through the menopause. About three million people in the UK are affected - one in three women over the age of 50.

The female hormone oestrogen reduces the amount of bone that is broken down and so helps to protect against osteoporosis. In women, the ovaries make oestrogen from puberty to the menopause. Any condition that reduces the number of years that a woman produces oestrogen, tends to increase the risk of osteoporosis. These conditions include:

• Early menopause (before the age of 45)
• Early hysterectomy (before the age of 45, especially if both ovaries are removed)
• Missing periods for six months or more as a result of over-exercising or over-dieting (especially due to anorexia).

Osteoporosis has been called the "silent disease". Most people affected are unaware that their bones are thinning until they experience a break, or notice more gradual signs such as height loss, or curvature of the spine (sometimes known as "dowager's hump"). The bones most likely to break as a result of osteoporosis are the hip, wrist and the vertebrae of the spine.