You may be wondering what to anticipate and how to get ready if you’ve been referred for a DEXA scan or if you’ve decided to get one for preventative health.
The good news? It’s a quick, non-invasive test that causes very little discomfort and takes less than half an hour. However, there are a few important things you should know before your appointment to guarantee accurate results and a seamless experience.
You can enter with confidence if you follow this guide, which explains what a DEXA scan entails, how to get ready, and what happens during and after the scan. A DEXA Scan has the same radiation equivalent of a 40 minute flight.
What Is a DEXA Scan?
Bone mineral density (BMD) can be measured with an imaging test called a DEXA scan, which stands for dual-energy X-ray absorptiometry. It is the most reliable and commonly used method for determining fracture risk, diagnosing osteoporosis, and tracking changes in bone over time.
DEXA is also used for body composition analysis in many clinics, providing comprehensive data on visceral fat, lean muscle mass, and body fat percentage.
Step-by-Step: How to Prepare for a DEXA Scan
1. Tell Your Provider About Any Recent Imaging
Inform the clinic if you have had any nuclear medicine studies or scans that use contrast dye in the last seven days, such as a CT scan or MRI with contrast. DEXA results may be affected by some of these, particularly if you are still taking contrast materials.
Tip: Try to arrange your DEXA scan at least five to seven days following any other contrast-agent-based imaging procedures.
2. Avoid Calcium Supplements Before the Test
Within 24 hours of your scan, avoid taking any calcium supplements, including tablets or antacids like Tums. Your bone density reading may be artificially elevated by calcium that appears on the scan.
Important: Only supplements are covered by this. You can continue to consume foods that naturally contain calcium.
3. Wear Comfortable Clothing (No Metal)
Wear loose, comfortable clothing that doesn’t contain any metal — this includes:
- Zippers
- Buttons
- Underwire bras
- Snaps or belts
Metal can interfere with the scan and may mean you’ll need to change into a gown at the clinic.
Pro tip: Athletic wear or leggings and a T-shirt with no logos or embellishments usually work best.
4. Arrive With an Empty Stomach (If Advised)
Fasting is not necessary for routine bone density scan. Unless instructed otherwise, you are free to eat and drink as usual.
To increase accuracy, especially when measuring visceral fat, some providers might advise fasting for a few hours prior to your DEXA scan if it also includes a body composition analysis.
Always abide by the guidelines your clinic has provided. Call in advance if you’re not sure.
5. Pause Intense Exercise Before Your Scan
Avoiding strenuous exercise or heavy weight training for the 24 hours before the scan is a smart idea, particularly if you’re getting a body composition scan.
Why? The precision of measurements of muscle mass and body fat can be marginally impacted by post-workout inflammation and fluid changes.
Save the gym for after your appointment; a leisurely stroll is acceptable.
6. Let the Technician Know if You’re Pregnant
Despite the extremely low radiation dose involved in DEXA scans, it is still crucial to inform the clinic if you are or may become pregnant. Depending on the circumstances, the test might be rescheduled or delayed.
It’s best to bring it up when you arrive if you’re not sure.
What to Expect on the Day
- You’ll lie on a cushioned table while the scanner arm moves slowly over your body.
- The scan typically takes 10–20 minutes, depending on the area being tested.
- The process is painless, there’s no noise, injection, or enclosed space.
- You’ll be asked to stay very still to ensure a clear image.
- The majority of scans concentrate on the hip, spine, and occasionally the forearm. Additionally, some facilities offer regional or full-body muscle and fat analyses.
After the scan, you can return to your normal activities immediately.
After the Scan: When Will You Get Results?
Depending on your provider, results are typically available in a few days.
A T-score (for bone density) and, if relevant, a breakdown of your body composition will be included in your report. The T-score assesses your risk of fracture by comparing your bone density to that of a young adult in good health.
Any subsequent actions, such as lifestyle modifications, additional testing, or, if necessary, the initiation of treatment, will be guided by the information provided by your physician or healthcare provider.
Final Tips
- Verify any special instructions from your clinic one more time, particularly those pertaining to clothing or fasting.
- Arrive early to complete paperwork and ask questions.
- If possible, bring your referral or previous scan results; these aid in monitoring changes over time.
One of the most accurate methods for determining body composition and bone health is a DEXA scan. A smoother experience on the day and accurate, practical results are guaranteed by thorough preparation.
References
- DEXAfit – How to Prepare for a DEXA Scan
https://www.dexafit.com/blog2/how-to-prepare-for-a-dexa-scan - DEXA Melbourne – Preparing for Your DEXA Scan (PDF)
https://www.dexamelbourne.com.au/wp-content/uploads/2018/02/Preparing-for-your-DEXA-scan.pdf - International Osteoporosis Foundation – Other Diagnostic Tools
https://www.osteoporosis.foundation/health-professionals/diagnosis/other-diagnostic-tools - Mayo Clinic – Bone Density Test
https://www.mayoclinic.org/tests-procedures/bone-density-test/about/pac-20385273