Various factors are known to increase the rate at which bone loss occurs.

These can be divided into three groups: factors you can do nothing about, things you can change and causes related to other medical conditions or drug therapy.

Listed below are the main conditions that can lead to osteoporosis.

Unchangeable causes of increased bone loss
Increasing age.
Family history of osteoporosis.
Being female.
Following menopause.
Being thin.

Changeable causes of increased bone loss
Inactivity.
Poor diet (low in calcium).
Smoking.
Increased alcohol intake

Medically related causes of increased bone loss
Steroid drug treatment, particularly if prolonged more than a few weeks.
Early menopause or the removal of the ovaries at a young age (under 45 years).
Hormone abnormalities such as over-activity of the thyroid gland or the glands that produce the body's natural steroids, or under-production of testosterone in men.
Chronic liver or kidney disease.
Vitamin D deficiency.