There’s so much confusion about “…what exactly is my DEXA scan telling me?” that I decided the topic of diagnostic testing for bone health deserves some space on the page…especially when there are so many other tests that can provide valuable information. In Part One of this series, we’ll cover what a DEXA scan is and how to interpret the information it provides.  In Part Two we’ll discover what the limitations of the DEXA scan are and why that shouldn’t be the only test to evaluate one’s bone health.

The Dual-Energy Xray Absorptiometry (DEXA) test is consider the gold standard for assessing bone density.  It measures bone density (BD) of the lumbar vertebrae and the neck of femur (the narrowest part of the femur) of the hip joint.  The results are given in numbers as grams per cubic centimeter (gm/cc) and provide a calculation as a T score and Z score.

The T score  compares your result with that of the ideal young standard of the same gender while the Z score compares your result with other people of the same sex and age.  So, if you are a woman having a DEXA scan, your T score represents the comparison of your bone density to that of a 30 year woman with peak bone mass.  Your Z score represents the comparison of your bone density to other women your age.

If you’ve had a DEXA scan done, you’ve probably wondered how the scoring system works and what it means to you in particular. 

Here’s the conventional interpretation:

  • T score of +1 to -1 = Excellent
    Your bone density is close to or even better than a younger person of the same sex  

  • T score of >-1.0 to -2.4 = Osteopenia
    Your bone density is less than, but not excessively less than, a younger person of the same sex 

  • T score of >-2.5 = Osteoporosis
    Your bone density is significantly less than a younger person of the same sex

This interpretation leaves a lot of people with more questions than answers about their bone health. 

Here’s what I tell my clients about their results:

  • If your T score is +1 to -1

    Congrats!  Your focus continues to be on how best to maintain your bone density and you probably achieved a great level of peak bone mass in your 20’s.

  • If your T score is >-1 to -2.4
    The level of concern depends on several factors:  

    • Is this your first DEXA scan?  

      If so, we can consider this your baseline, especially if you have a slighter build, because we know that women who fall in that category naturally have slightly lower bone density

    • Perhaps, for a variety of reasons, you may not have achieved peak bone mass as a young adult and that is reflected in the DEXA scan (More about Peak Bone Mass in future post)

    • Are you in the late peri-menopausal years or in the first 5 years of menopause?

      - We know that the loss of estrogen during this time period contributes significantly to the acceleration of bone loss – up to 10% in that time period – and then it should stabilize

      - A follow up DEXA scan will tell us more but you’d have to wait at least 2 years for the next insurance-approved test.  Maybe its time to think about other tests that can help track the trend sooner (More about that in the next series)

    • Its important to remember that a diagnosis of osteopenia does NOT mean that you are destined for osteoporosis or that you will automatically suffer a fracture

    • It does mean that prioritizing your bone health is in your best interest and working with a practitioner who can help you uncover less obvious causes of loss of bone density would be helpful (see Causes of Bone Loss)

Causes of Bone Loss

  • If your T score is >2.5

    • You are dealing with osteoporosis and there may be concern for fracture

    • Its time to ramp up your approach by addressing other disorders that contribute to bone loss, tracking your bone density with more frequent functional diagnostics, ensuring a bone-centric food plan and movement routine as well as looking at pros and cons of the medications offered


DEXA results vary considerably…so here are my recommendations to minimize the variations and ensure your most accurate results:

  • Results fluctuate with the seasons, especially in the northern hemisphere with decrease access to sunlight and Vitamin D production.  

Recommendation:  Schedule your DEXA scans at the same time of year

  • Results vary with the type and age of the machine being used, the skill set of the technician operating that machine. And reference ranges for computing the T score and Z score vary from facility to facility.

Recommendation:  Schedule your test to be done at the same facility and, if possible, with the same technician

  • Often times only the summary page is offered for your review.  The problem here is that the summary provides results of all sites, lumbar spine and hip, grouped together whereas the full report will allow you to compare the results for each area with itself for a more accurate understanding and better tracking per site

Recommendation:  Ask for the full report of your DEXA results, not just the summary page.  And don’t hesitate to ask for help interpreting the results

  • Take a deep breath!  Remember that with all the variations, a 5-6% change is not significant.  And when you do need to be concerned, there are many choices you can make to improve your bone health naturally.

Hopefully this post will help clarify what information a quality DEXA scan can provide.  In Part Two of this series I’ll discuss more about the limitations of relying on the DEXA scan alone to determine fracture risk.

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