A DXA scan (you might also see it written as DEXA) is a common imaging test used to measure bone mineral density. It’s often described as easy to do, and for most people it is—but it also helps to know what it can (and can’t) tell you, who benefits most from having one, and what the results actually mean for your fracture risk.
What a DXA scan measures (and what it doesn’t)
DXA stands for dual-energy X-ray absorptiometry. In plain terms, it uses two low-dose X-ray beams to estimate how much mineral (mainly calcium) is in your bones, typically at the hip and spine. Those areas matter because low density there is strongly linked with higher fracture risk.
What it doesn’t do is directly “test bone strength” in a complete way. Bone strength also depends on bone quality, structure, and factors like fall risk, medications, and medical conditions. DXA is a key piece of the puzzle, but it’s not the whole picture.
What the appointment is like
Most DXA scans are quick. You usually lie on a padded table while a scanner passes over your body; you’re not enclosed like you would be in an MRI. The test is painless, and you can breathe normally while staying still for short periods.
Preparation is usually simple: wear clothing without a lot of metal (zippers, thick buckles), and tell the facility if you’ve recently had contrast imaging (like a CT scan with contrast or certain nuclear medicine tests), because that can affect timing. If you take calcium supplements, some clinics ask you to avoid them for a short window beforehand—follow the instructions you’re given.
Who’s most likely to be advised to get one
DXA scanning is commonly used for people at higher risk of osteoporosis or fractures. That includes many older adults, especially after menopause, because bone loss can accelerate with age and hormonal changes. Clinicians may also recommend testing earlier if you’ve had a fracture from a minor fall or injury that wouldn’t normally break a bone.
Other reasons include long-term use of medications that can weaken bones (glucocorticoids like prednisone are a classic example), certain endocrine conditions, or medical issues that affect nutrient absorption. If your personal or family history suggests elevated risk, a DXA can help guide prevention and treatment decisions.
Understanding T-scores, Z-scores, and what “osteopenia” means
DXA results are often reported as a T-score and sometimes a Z-score. The T-score compares your bone density to that of a healthy young adult reference group, while the Z-score compares you to people your own age and sex. Your clinician uses these numbers, along with your health history, to interpret what’s going on.
You may hear the term “osteopenia,” which generally means bone density is lower than expected but not in the osteoporosis range. It doesn’t automatically mean you’ll have a fracture, and it doesn’t always mean you need medication. It does mean it’s worth taking bone health seriously—especially if other risk factors are in play.
Why bone density isn’t the same as fracture risk
Fracture risk is influenced by more than bone density alone. Falls are a major driver—things like balance, vision, muscle strength, and home hazards can matter as much as (or more than) the DXA number. Lifestyle factors such as smoking, heavy alcohol use, very low body weight, and low physical activity can also increase risk.
That’s why many clinicians combine DXA findings with a broader risk assessment. The goal is to decide what level of intervention makes sense for you, from exercise and nutrition changes to medication when the risk is high enough to justify it.
What happens after the scan: practical next steps
If your results are normal, you may simply be advised to maintain healthy habits and repeat testing only if your risk changes. If your bone density is low, the first steps often include strength and balance training, adequate dietary calcium, sufficient vitamin D (if you’re low), and addressing any reversible causes of bone loss. If you’ve had a recent fracture or your risk is high, your clinician may discuss prescription options that reduce fracture risk.
Follow-up timing varies. Some people don’t need frequent repeats, while others—such as those starting or changing treatment, or those with significant risk factors—may be advised to recheck on a schedule tailored to their situation. If you’re unsure whether you need a DXA or when to repeat one, ask what decision the test will help make; that question usually clarifies whether it’s the right move now.
For most people, a DXA scan is a straightforward way to get a clearer read on bone density and help guide prevention. The most useful results come when they’re interpreted in context—your age, health history, medications, and fall risk—so you can focus on the steps that actually lower the chances of a fracture.