A bone density test, also known as a dual-energy X-ray absorptiometry (DEXA) scan, is a type of X-ray that measures the strength of your bones. It is used to diagnose osteoporosis, a condition that causes bones to become weak and brittle. Osteoporosis can lead to fractures, especially of the hip, spine, and wrist.

How is a bone density test performed?

A bone density test is a painless and non-invasive procedure that does not require any special preparation. You will be asked to lie on a padded table while a machine passes over your body. The machine will emit two beams of X-rays, one with a high energy level and one with a low energy level. The amount of X-rays that are absorbed by your bones will be measured, and this information will be used to calculate your bone density.

What are the results of a bone density test?

The results of a bone density test are usually returned as a series of numbers: a T Score and a Z Score.

  • T Score: The T Score indicates how dense your bones are compared to an average healthy patient in their 20’s (when bone density is usually the strongest). A T Score of -2.5 or lower indicates osteoporosis.
  • Z Score: The Z Score indicates the density of your bones compared to the average density of patients in your age group. A Z Score of -2 or lower indicates that your bone density is below average for your age.

Who should have a bone density test?

Women over the age of 65 and men over the age of 70 should have a bone density test at least once. Other people who may need a bone density test include:

  • People with a family history of osteoporosis
  • People with certain medical conditions, such as rheumatoid arthritis or chronic kidney disease
  • People who are taking medications that can cause bone loss, such as corticosteroids

What are the benefits of a bone density test?

A bone density test can help to diagnose osteoporosis early on, when it is most treatable. Treatment for osteoporosis can help to prevent fractures and other complications.

How can I improve my bone density?

There are a number of things you can do to improve your bone density, including:

  • Getting regular exercise
  • Eating a healthy diet that is rich in calcium and vitamin D
  • Taking calcium and vitamin D supplements if you are not getting enough from your diet
  • Avoiding smoking and excessive alcohol consumption

If you have any questions about bone density tests, please talk to your doctor.