How Do I Prepare for a DEXA Scan? What to Expect

Medically Reviewed on 10/7/2022
How Do I Prepare for a DEXA Scan
You do not need to do anything to prepare for a DEXA scan besides stopping taking calcium supplements 24 hours beforehand

A DEXA (dual-energy X-ray absorptiometry) scan measures bone mineral density and checks for bone loss. Your bones tend to lose density as you get older, and a DEXA scan can help determine your risk of developing osteoporosis and other bone disorders.

Because DEXA scans are outpatient procedures, you do not need to do anything to prepare for the scan besides stopping taking calcium supplements 24 hours beforehand.

Here is what to expect before, during, and after a DEXA scan.

What to expect before a DEXA scan

Before a DEXA scan, discuss the procedure with your doctor. You may have to complete a questionnaire about your present state of health, any medical conditions you have, and any history of fractures before you consent to the procedure.

Take these steps before your test:

  • Stop taking calcium supplements 24 hours before: This includes multivitamins and antacids (commonly used to treat heartburn).
  • Wear loose-fitting clothing: Wear comfortable clothing with as little metal as possible (zippers, buttons, or buckles). A cotton shirt and sweatpants would be appropriate.
  • Inform your doctor if you might be pregnant: DEXA scans use low levels of radiation. Medical professionals advise avoiding all types of radiation exposure during pregnancy.

How is a DEXA scan conducted?

A DEXA scan is performed without anesthesia and does not involve injections or needles.

 A DEXA scan is quite similar to an X-ray. You may need to stand before a machine (an X-ray plate) or lie down on a bed until specific areas are X-rayed. Your lumbar spine and hip will be examined using X-rays

The entire procedure does not take more than 10 to 15 minutes.

Bone calcium levels will indicate bone density and bone strength. These results are compared to a database of healthy people, and standard deviations from the norm are reported as a T-score.

According to WHO guidelines, osteopenia is defined as having a T-score between -1 and -2.5 (standard deviations below the mean), and osteoporosis is defined as having a T-score below -2.5.

What to expect after a DEXA scan

DEXA scans are quick and painless. After the test, you should be able to carry on with your normal activities right away.

Your results will be evaluated by specialists who are qualified to interpret DEXA images, and a report will be provided to your physician.

Test results will be explained to you by your doctor, who may offer suggestions on improving or maintaining bone health such as dietary and lifestyle modifications that can help minimize your risk of bone loss or fractures.


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What is the purpose of a DEXA scan?

DEXA scans are used to determine your risk of both osteoporosis and fractures. As a rule, the denser your bones, the stronger they are.

Although older women are at higher risk of osteoporosis, men can develop the condition as well, especially if they are taking certain medications (glucocorticoids and antacids) known to affect bone porosity. 

Your doctor may recommend a bone density test regardless of your gender or age if you have:

  • Loss of height: Osteoporosis is one of the main causes of compression fractures in the spine, which can occur in people who have lost at least 1.5 inches (3.8 cm) of height.
  • Bone fracture: Bones can become so weak that they break much more easily than they should, leading to fragility fractures. A minor fall can sometimes result in fragility fractures.
  • Used certain medicines: Osteoporosis can result from long-term use of steroid medications such as prednisone because they inhibit the bone-rebuilding process.
  • Drop in hormones: Low sex hormone levels can weaken bones. Female estrogen levels naturally decline after menopause and may decrease with specific cancer therapies. Male testosterone levels may be lower due to prostate cancer treatments.
Medically Reviewed on 10/7/2022
Image Source: iStock image

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