Cookies on the Bupa website

We use cookies to help us understand ease of use and relevance of content. This ensures that we can give you the best experience on our website. If you continue, we'll assume that you are happy to receive cookies for this purpose. Find out more about cookies



DXA scan (dual energy X-ray absorptiometry)

A dual energy X-ray absorptiometry (DXA or DEXA) scan measures your bone density. It can look for signs of fragile (brittle) bones to assess your risk of a fracture (break).

You will meet the radiographer carrying out your procedure to discuss your care. It may differ from what is described here as it will be designed to meet your individual needs.

A DXA scan uses X-ray equipment and a computer to measure the density of your bones.

A DXA scan projects X-rays onto your bones. Some of this radiation travels straight through your bones and a certain amount is absorbed by them. How much is absorbed depends on how dense your bones are. A device called a detector measures how much radiation passes through your bones and it sends the information to a computer. This works out an average bone density score. Your score will be compared with normal measurements for both a young, healthy adult, and to people your own age, size and gender. Low scores indicate that your bones are fragile and more likely to fracture.

Doctors use DXA scans to assess your risk of developing osteoporosis. This is a condition where your bones lose their density and become weak, brittle and more likely to fracture. Your doctor may advise you to have a DXA scan if you fracture a bone after only a minor bump or fall. You may also need to have a DXA scan if you’re at a high risk of osteoporosis. Doctors also use DXA scans to monitor how well you respond to treatment for osteoporosis.

You may need to have a DXA scan if you have another health condition that can affect the density of your bones. These include eating disorders, such as anorexia nervosa, and kidney disease.

A DXA scan is quick and painless, and both adults and children can have the scan.

Read more Close


  • Preparation Preparing for a DXA scan

    DXA scans are usually done as a hospital outpatient procedure in the imaging or radiology department.

    Your radiographer (a health professional trained to perform imaging procedures) will explain how to prepare for your scan.

    If you usually take any medicines, continue to take them unless your doctor or radiographer tells you not to. However, don't take calcium supplements for at least 24 hours before your scan.

    It's best to wear light clothing that doesn't have any metal fasteners. Your radiographer may ask you to remove any metal jewellery because this can interfere with the scan.

    Your radiographer will discuss with you what will happen before, during and after your scan. This is your opportunity to understand what will happen. You can help yourself by preparing questions to ask about the risks, benefits and any alternatives to the procedure. This will help you to be informed, so you can give your consent for the procedure to go ahead. You may be asked to sign a consent form.

  • Alternatives What are the alternatives to a DXA scan?

    Alternative imaging tests, such as an ultrasound, X-ray or CT scan, can assess your risk of a fracture. However, some of these tests aren't as reliable as DXA scans. Also, CT scans use a larger dose of radiation than DXA scans.

    Blood and urine tests can check the levels of chemicals, such as calcium, that are produced when your body breaks down and forms new bone. This can provide information about factors that might affect your bone strength but they can’t directly diagnose osteoporosis or bone strength.

  • The procedure What happens during a DXA scan?

    The scan will usually take between 10 and 20 minutes.

    Your radiographer may ask you to remove certain items of clothing or to wear a gown. You will lie on a padded table during the scan. Your radiographer may position different parts of your body to improve the images. For example, to assess your hip, he or she may put your foot in a brace that will rotate your hip inwards.

    Your radiographer will operate the scanner from behind a wall or an adjoining room. However, he or she will be able to see, hear and speak to you during the procedure.

    The X-ray machine will slowly pass over your body and send X-rays through the bones that your radiographer is testing. A detector will measure how much X-ray radiation passes through your bones and send this information to a computer. It’s important to lie very still as each bone is scanned. Your radiographer may ask you to hold your breath for a few seconds while he or she takes the X-ray picture. This will help to prevent a blurred image.
  • Bupa On Demand

    Discover how you can access a range of private treatments on a pay-as-you-go basis with Bupa On Demand.

  • Aftercare What to expect afterwards

    You will usually be able to go home when you feel ready.

    Your radiographer will send your scan to a radiologist, who will prepare a report. A radiologist is a doctor who specialises in using imaging methods to diagnose medical conditions. The report will then be forwarded to your GP. This can take several days. Before you go home, ask your radiographer when you can expect to get your results.

    Results of a DXA scan

    The results of the scan are given as a T-score. This is a measure of how your bone density compares with the normal average for young, healthy adults.

    • A T-score of between 0 and -1 means your bone density is normal.
    • If your T-score is between -1 and -2.5, you’re classed as having osteopenia. This means your bone density is lower than normal, but you don't yet have osteoporosis.
    • A T-score below -2.5 is classed as osteoporosis.

    If your T-score indicates that you may have osteopenia or osteoporosis, your GP will give you advice about treatment options. You may be referred to see a specialist, such as a rheumatologist. Your GP will consider both the T-score and other risk factors when he or she gives you advice about treatment to help prevent fractures.

    A DXA scan will also give you a Z-score. This compares your bone density with that of people your own age, size and gender. If your score is lower than the average, you may need to have further tests.

  • Risks What are the risks?

    As with every procedure, there are some risks associated with a DXA scan. We haven't included the chance of these happening as they are specific to you and differ for every person. Ask your doctor or radiographer to explain how these risks apply to you.

    During the scan you will be exposed to some X-ray radiation. However, the dose is very low and roughly a tenth of that used for a chest X-ray. It's one of the lowest doses of radiation used in medical procedures.

    If you’re pregnant

    If you’re pregnant, or think you might be, it's important to let your GP or radiographer know. You might not be able to have a DXA scan as there is a risk that the radiation could harm your unborn baby. However, it depends on why you need a scan. Ask your doctor or radiographer for advice.

  • FAQs FAQs

    I'm a 79-year-old woman and broke my wrist in a recent fall. Do I need to have a DXA scan?


    You may need to have a DXA scan but speak to your GP. You may also need to start treatment to help prevent any further breaks (fractures).


    DXA scans can help doctors to spot people who are at high risk of developing osteoporosis and who could benefit from treatment to prevent fractures.

    If you're over 65 (particularly if you're a woman), you already have a greater risk of getting osteoporosis than when you were younger. Having had a wrist fracture also may suggest that you have fragile bones.

    Speak to your GP for advice and information about starting treatment to help prevent fractures.

    What will happen if I'm classed as having osteopenia?


    If you have a DXA scan and are diagnosed with osteopenia, your GP is likely to advise you to make some changes to your lifestyle.


    Having osteopenia means you have a lower bone density than normal and could be at risk of developing osteoporosis. If you get a diagnosis of osteopenia after your DXA scan, your GP will probably suggest you make some changes to your lifestyle. These can help to slow down the possible progression to osteoporosis and therefore reduce your risk of fracturing a bone. Your GP may recommend the following lifestyle changes.

    • Include more calcium in your diet. Foods high in calcium include milk, cheese, yoghurt, sardines and green vegetables such as broccoli and cabbage. Your doctor may advise you to take vitamin D supplements too as they help your body to absorb calcium.
    • Carry out regular, low-impact, weight-bearing exercise, such as walking.
    • If you smoke, try to stop.
    • Drink alcohol in moderation. Stick to the recommended daily limits set by the Department of Health. This is no more than two to three units a day for women, and three to four units a day for men.

    Your doctor won't usually prescribe you any medicines if your bone density isn't low enough for you to be diagnosed with osteoporosis. However, you may need to have another DXA scan two to five years later to check if your bones have lost more density.

    Will a scan on my heel show whether I have osteoporosis?


    A DXA scan of your heel can help to predict if you will have a fracture (break) but they aren't usually used to diagnose osteoporosis. This is because the bone density in your heel isn't always a good indication of the density in your other bones. A scan of your hip and spine is considered the 'gold standard' for diagnosing osteoporosis.


    A scan of your hip and spine is considered to be the most reliable method to diagnose osteoporosis and to predict the risk of fractures. This is partly because international statistics that enable your risk of fractures to be worked out are based on scans of these bones. Also, a fractured hip is one of the most serious consequences of osteoporosis. The best way to predict it is to scan the hip rather than any other bone.

    Alternative scanners are available that can measure the bone density of your heel and other bones including those in your forearm, finger and hand. These are known as peripheral scans and are sometimes used in screening to see whether you may need further investigations.

    If you have a peripheral scan that shows you have a low bone density, you're likely to need a hip and spine DXA. This will confirm the findings.

    Will I have a repeat DXA scan to check if my treatment for osteoporosis is working?


    You will usually only need to have another scan if you fracture a bone after a minor bump or fall.


    If you haven't broken any bones while taking a treatment for osteoporosis, it's thought to be enough evidence that your treatment is working well. It's not usually necessary to have another DXA scan just to check up on your progress.

    If you do fracture (break) a bone while taking a treatment for osteoporosis, your GP may refer you to see a specialist. You might need to have another scan. However, you won't usually have a repeat scan unless you have been on treatment for at least two years (less if you take steroids). This is because it can take up to two years for the treatment to have a beneficial effect on your bones.

    If a repeat scan shows that your bone density is still below normal, you might need to try another type of treatment.

  • Resources Resources

    Further information


    • ACR-SPR-SSR practice guideline for the performance of dual-energy X-ray absorptiometry (DXA). American College of Radiology., published 2013
    • Bone densitometry. Radiological Society of North America., published 22 April 2013
    • Guideline for the diagnosis and management of osteoporosis in postmenopausal women and men from the age of 50 years in the UK. National Osteoporosis Guideline Group., published May 2013
    • Osteoporosis: fragility fracture risk. National Institute for Health and Care Excellence (NICE), August 2012.
    • Scans and tests and osteoporosis. National Osteoporosis Society., published August 2013
    • Osteoporosis. Medscape., published 4 October 2013
    • ACR appropriateness criteria. American College of Radiology., published 2010
    • Having a bone density test. National Osteoporosis Foundation., accessed 4 December 2013
    • Clinician’s guide to prevention and treatment of osteoporosis. National Osteoporosis Foundation., published 2013
    • ACR-SPR practice guideline for imaging pregnant or potentially pregnant adolescents and women with ionizing radiation. American College of Radiology., published 2013
    • Osteoporosis management. Map of Medicine., published 16 October 2013
    • Calcium. Food Standards Agency., accessed 5 December 2013
    • Rizzoli R, Boonen S, Brandi ML, et al. Vitamin D supplementation in elderly or postmenopausal women: a 2013 update of the 2008 recommendations from the European Society for Clinical and Economics Aspects of Osteoporosis and Osteoarthritis. Curr Med Res Opin 2013; 29(4):1–9. doi:10.1185/03007995.2013.766162
    • Alcohol labelling. Department of Health., published 3 February 2012
    • Osteoporosis – prevention of fragility fractures. NICE Clinical Knowledge Summaries., published September 2013
    • Patients. International Society for Clinical Densitometry., published 25 November 2013
    • 2013 ISCD official positions – adult. International Society for Clinical Densitometry., published 15 August 2013
    • Calculation tool. World Health Organization Collaborating Centre for Metabolic Bone Diseases., accessed 5 December 2013
    • Welcome to the QFracture-2012 risk calculator. QFracture., published 2012
  • Has our information helped you? Tell us what you think about this page

    We’d love to know what you think about what you’ve just been reading and looking at – we’ll use it to improve our information. If you’d like to give us some feedback, our short form below will take just a few minutes to complete. And if there's a question you want to ask that hasn't been answered here, please submit it to us. Although we can't respond to specific questions directly, we’ll aim to include the answer to it when we next review this topic.

    Let us know what you think using our short feedback form
    Ask us a question
  • Related information Related information

  • Author information Author information

    Produced by Rachael Mayfield-Blake, Bupa Health Information Team, February 2014.

    Let us know what you think using our short feedback form
    Ask us a question

About our health information

At Bupa we produce a wealth of free health information for you and your family. We believe that trustworthy information is essential in helping you make better decisions about your health and care. Here are just a few of the ways in which our core editorial principles have been recognised.

  • Information Standard

    We are certified by the Information Standard. This quality mark identifies reliable, trustworthy producers and sources of health information.
    Information standard logo
  • HONcode

    This site complies with the HONcode standard for trustworthy health information: verify here.

    This website is certified by Health On the Net Foundation. Click to verify.

What our readers say about us

But don't just take our word for it; here's some feedback from our readers.

Simple and easy to use website - not alarming, just helpful.

It’s informative but not too detailed. I like that it’s factual and realistic about the conditions and the procedures involved. It’s also easy to navigate to areas that you specifically want without having to read all the information.

Good information, easy to find, trustworthy.

Meet the team

Image of Andrew Byron

Andrew Byron
Head of health content and clinical engagement

  • Dylan Merkett – Lead Editor – UK Customer
  • Nick Ridgman – Lead Editor – UK Health and Care Services
  • Natalie Heaton – Specialist Editor – User Experience
  • Pippa Coulter – Specialist Editor – Content Library
  • Alice Rossiter – Specialist Editor – Insights
  • Laura Blanks – Specialist Editor – Quality
  • Michelle Harrison – Editorial Assistant

Our core principles

All our health content is produced in line with our core editorial principles – readable, reliable, relevant – which are represented by our diagram.

An image showing or editorial principals

                  Click to open full-size image

The ‘3Rs’ encompass everything we believe good health information should be. From tweets to in-depth reports, videos to quizzes, every piece of content we produce has these as its foundation.


In a nutshell, our information is jargon-free, concise and accessible. We know our audience and we meet their health information needs, helping them to take the next step in their health and wellbeing journey.


We use the best quality and most up-to-date evidence to produce our information. Our process is transparent and validated by experts – both our users and medical specialists.


We know that our users want the right information at the right time, in the way that suits them. So we review our content at least every three years to keep it fresh. And we’re embracing new technology and social media so they can get it whenever and wherever they choose.

Our accreditation

Here are just a few of the ways in which the quality of our information has been recognised.

  • The Information Standard certification scheme

    You will see the Information Standard quality mark on our content. This is a certification programme, supported by NHS England, that was developed to ensure that public-facing health and care information is created to a set of best practice principles.

    It uses only recognised evidence sources and presents the information in a clear and balanced way. The Information Standard quality mark is a quick and easy way for you to identify reliable and trustworthy producers and sources of information.

    Certified by the Information Standard as a quality provider of health and social care information. Bupa shall hold responsibility for the accuracy of the information they publish and neither the Scheme Operator nor the Scheme Owner shall have any responsibility whatsoever for costs, losses or direct or indirect damages or costs arising from inaccuracy of information or omissions in information published on the website on behalf of Bupa.

  • British Medical Association (BMA) patient information awards

    We have received a number of BMA awards for different assets over the years. Most recently, in 2013, we received a 'commended' award for our online shared decision making hub.

Contact us

If you have any feedback on our health information, we would love to hear from you. Please contact us via email: Or you can write to us:

Health Content Team
Bupa House
15-19 Bloomsbury Way

Find out more Close

Legal disclaimer

This information was published by Bupa's Health Content Team and is based on reputable sources of medical evidence. It has been reviewed by appropriate medical or clinical professionals. Photos are only for illustrative purposes and do not reflect every presentation of a condition.

The information contained on this page and in any third party websites referred to on this page is not intended nor implied to be a substitute for professional medical advice nor is it intended to be for medical diagnosis or treatment. Third party websites are not owned or controlled by Bupa and any individual may be able to access and post messages on them. Bupa is not responsible for the content or availability of these third party websites. We do not accept advertising on this page.

For more details on how we produce our content and its sources, visit the 'About our health information' section.

ˆ We may record or monitor our calls.