DEXA scans use very low levels of radiation, significantly less than many common medical imaging tests.
A full-body DEXA scan exposes you to about the same radiation as a short airplane flight. Because of this, DEXA is considered safe for general use when performed appropriately.
DEXA scans are not performed during pregnancy, and clinics follow strict safety protocols.
How Much Radiation Is in a DEXA Scan? What You Need to Know
One of the most common questions people ask before getting a DEXA scan is simple and understandable:
“How much radiation does a DEXA scan use?”
The short answer: very little—especially compared to most medical imaging tests and even everyday environmental exposure.
This article breaks down what DEXA radiation really means, how it compares to common activities, and why DEXA is widely used for body composition and bone density measurement.
What Is a DEXA Scan?
A DEXA scan (Dual-Energy X-ray Absorptiometry) uses two very low-energy X-ray beams to measure:
- Body fat
- Lean muscle mass
- Bone mineral density
Because the energy levels are low and tightly controlled, radiation exposure is kept to a minimum.
How Much Radiation Is in a DEXA Scan?
A typical full-body DEXA scan exposes you to approximately 1–5 microsieverts (µSv) of radiation.
To put that into perspective, this is significantly lower than most diagnostic imaging tests and it is comparable to natural background radiation you receive in daily life
Exact exposure can vary slightly by machine and scan type, but it remains very low.
DEXA Radiation Compared to Everyday Activities
Here’s how a DEXA scan stacks up against common sources of radiation exposure:
DEXA scan: ~1–5 µSv
- One day of natural background radiation: ~8–10 µSv
- Cross-country flight: ~30–40 µSv
- Chest X-ray: ~100 µSv
- CT scan: 1,000+ µSv
In simple terms, a DEXA scan often exposes you to less radiation than you receive naturally in a single day.
Why Is DEXA Radiation So Low?
DEXA machines are specifically designed to:
- Use low-energy X-rays
- Focus only on the area being scanned
- Minimize scatter and unnecessary exposure
Unlike CT scans, which capture detailed 3D images, DEXA focuses on measurement, not diagnosis—allowing for much lower radiation levels.
Is a DEXA Scan Safe?
DEXA scans are considered safe for general use when performed appropriately. The key points are that unlike a CT Scan there are no needles or contrast agents required to administer the test and there is no recovery time. In addition, a DEXA Scan provides very low radiation exposure making it one of the easiest and safest tests to measure bone health and body composition.
DEXA scans are not performed during pregnancy, and clinics follow strict safety protocols.
How Often Can You Get a DEXA Scan?
Because radiation exposure is minimal, DEXA scans can be used for trend tracking over time.
Best-practice frequency:
Body composition: every 3 months
Bone density: every 12–24 months
Consistency and meaningful change matter more than frequent scanning.
Why Radiation Concerns Should Be Put in Context
Radiation is often discussed as a single category, but dose matters.
DEXA uses:
- A very small dose
- A short exposure time
- Technology designed specifically for measurement, not diagnosis
For most people, the benefit of accurate body composition or bone density data outweighs the minimal radiation exposure.
Common Questions
Does a DEXA scan use more radiation than an X-ray?
No. A DEXA scan typically uses far less radiation than a standard X-ray.
Is DEXA radiation cumulative?
All radiation exposure is technically cumulative, but the dose from DEXA scans is extremely low compared to everyday exposure.
Can you feel radiation during a DEXA scan?
No. A DEXA scan is painless and you do not feel radiation during the scan.
Final Takeaway
A DEXA scan uses one of the lowest radiation doses of any imaging technology available today. For individuals tracking body composition or bone density, it provides valuable insight with minimal exposure—often less than what you experience naturally in daily life.
Understanding the actual numbers helps replace fear with facts.
