A bone density scan is a safe and painless procedure which involves being exposed to a small dose of ionising radiation (X-rays). It measures the density of the bones at the hip and lower spine, and calculates a score of the average bone density. A low score indicates that the bone is fragile and therefore more likely to fracture.

You could be advised to have a bone density scan if your healthcare practitioner suspects that you have, or are at risk of developing, osteopenia or osteoporosis.

Osteopenia refers to early signs of loss to bone mineral density which could lead to osteoporosis. Not everyone who has osteopenia will develop osteoporosis.

Osteoporosis is a disease where the density and quality of the bones are reduced. As the bone becomes more porous and fragile the risk of fracture greatly increases.

The risk of developing osteopenia/osteoporosis increases with age as the bones become thinner naturally. Both men and women lose a small amount of bone each year after the age of 30. 

For women there is usually a more rapid bone loss when the production of the hormone oestrogen slows down (usually between the age of 45 – 55), therefore for women who go through the menopause early, or have a hysterectomy this can increase the risks. 

For men the thinning of the bones develops gradually as the production of the hormone testosterone slows down, usually when they reach the age of 45-50. 

Osteoporosis doesn’t usually affect people until after the age of 60, and typically affects far more women than men, as women on average have smaller and lighter bones than men. 

• Developing osteopenia / osteoporosis depends on the bone density in early life, as well as health, diet and physical activity. There are many factors listed below which can increase the risks for both sexes:
• Family history of osteoporosis – if the mother, father or sibling has been diagnosed with osteoporosis, or has experienced broken bones from a minor injury, there is an increased risk of developing the disease
• Certain medical conditions such as rheumatoid arthritis, coeliac disease, anorexia nervosa, hyperparathyroidism, and hyperthyroidism
• Taking certain medications (for example long term use of steroids) 
• Lifestyle factors – these include smoking; heavy alcohol use; leading an inactive lifestyle with little, or no weight bearing exercise; being small framed, thin or underweight; malnutrition; a diet low in calcium and vitamin D; high intake of fizzy drinks which contain phosphoric acid