Bone-Density vs Body-Composition DEXA: What Differs
Bone-density DEXA answers a fracture-risk question; body-composition DEXA measures fat and lean mass. New Dawn Health runs both in one 20-minute DEXA Scan for $109.
Quick answer: Bone-density DEXA and body-composition DEXA use related technology but answer different questions. A body-composition service is not automatically a diagnostic osteoporosis examination, and a wellness scan does not establish a need for repeated medical imaging. New Dawn Health's DEXA Scan is $109 and runs both protocols in one 20-minute appointment.
What is the difference between a bone-density DEXA and a body-composition DEXA?
Both use dual-energy X-ray absorptiometry, but the acquisition, analysis software, output and intended use differ.
| Bone-density DEXA | Body-composition DEXA | |
|---|---|---|
| Question answered | Is bone mineral density low enough to diagnose osteoporosis and estimate fracture risk? | How much fat and lean mass is there, and where is it distributed? |
| Sites measured | Hip and spine, the bones that break most often | Whole body, reported by region |
| Main output | T-score and Z-score | Fat mass, lean mass and their distribution |
| Diagnostic thresholds | T-score of −1 or higher is healthy bone; −1 to −2.5 is low bone mass; −2.5 or lower is osteoporosis | None; no diagnostic cut-off is defined |
| Clinical status | Screening and diagnostic examination | Measurement, not a diagnosis |
A T-score compares your bone to a young adult of the same sex at peak bone mass; a Z-score compares it to others of your age, size and sex. A body-composition result should not be used to diagnose osteoporosis unless the protocol and interpretation meet the requirements for that purpose.
Who should have a bone-density DEXA?
The US Preventive Services Task Force, in its January 2025 recommendation, advises screening for osteoporosis in women 65 years or older, and in postmenopausal women younger than 65 who are at increased fracture risk. Both carry a B grade. For men the Task Force concluded the evidence is insufficient to assess the balance of benefits and harms, an I statement — individual risk factors may still justify testing, but there is no population recommendation.
How often should a DEXA scan be repeated?
There is no universal repeat schedule. The Task Force notes that repeating bone-density testing at an interval of 4 to 8 years does not improve the accuracy of fracture prediction. Timing depends on the indication, the baseline result, treatment, the expected rate of change and whether a new result would change care. Very short intervals may measure normal variability rather than real biological change.
How much radiation does a DEXA scan use?
RadiologyInfo, published by the Radiological Society of North America and the American College of Radiology, puts the approximate effective dose of bone densitometry at 0.001 mSv, about three hours of natural background radiation. A chest X-ray is listed at 0.1 mSv, about ten days. The exact dose still varies by equipment and protocol, so treat any single fraction-of-a-chest-X-ray promise as an approximation rather than a specification. Positioning, calibration, software, body size and artefact all affect the measurement, so serial studies should be compared on a consistent protocol.
How much does a DEXA scan cost at New Dawn Health?
The DEXA Scan is $109 as a stand-alone booking. It covers whole-body composition and bone-density loss in one 20-minute appointment, and includes a CD of the imaging files and an English report of results in 7 to 10 business days. Fasting is 2 hours.
DEXA is also included in two full-body packages: Complete at $1,699 and Plus at $3,099. In the Light package at $1,399 it is an available add-on rather than an included scan.
What should you confirm before booking?
- Whether the service is bone density, body composition or both.
- The body sites, equipment, software and who interprets the result.
- Whether the report includes T-scores, Z-scores or body-composition outputs, and which are clinically appropriate for you.
- Pregnancy or possible pregnancy — disclose it before the scan.
- Price, currency, report, consultation and the as-of date.
Sources
- US Preventive Services Task Force — Osteoporosis to Prevent Fractures: Screening (accessed 2026-09-08)
- RadiologyInfo.org (RSNA and ACR) — Bone Density Scan (DEXA) (accessed 2026-09-08)
- RadiologyInfo.org (RSNA and ACR) — Radiation Dose in X-Ray and CT Exams (accessed 2026-09-08)
- NIAMS, National Institutes of Health — Bone Mineral Density Tests: What the Numbers Mean (accessed 2026-09-08)
US / UK terms and the closest Taiwan context
Read this first: These are comparison aids, not claims that coverage, credentials, or care pathways are equivalent. Europe is not one health system; UK examples below refer specifically to NHS England.
Radiology report, DICOM, and PACS
- What it means there
- A radiology report is the clinician’s interpretation. DICOM (Digital Imaging and Communications in Medicine) is the international standard for medical images and related information. PACS is a system used to store and retrieve imaging data.
- Closest Taiwan context
- Taiwan facilities may use the same international imaging standards, but the available export medium, viewer, report language, and delivery time are facility-specific.
- Do not treat as equivalent
- Receiving a PDF report does not necessarily mean the diagnostic images are included. Receiving DICOM files does not replace a signed clinical report or guarantee that another facility can import every file.
- What to ask
- Ask separately for the signed report, report language, complete DICOM study, delivery method, viewer needs, release timing, and any fee.