The acronym DEXA stands for Dual Energy X-ray Absorptiometry. Now that may sound very much like something from Star Trek, and in some ways the technology wouldn’t be out of place there. However DEXA is a perfectly safe form of x-ray that not only creates a transparent image of your body’s make up, but it can also specifically identify three principal elements that go to make up your body. Bone, lean tissue and fat. Not only that, but a DEXA body composition scan does this for your whole body, arms, legs and trunk, not just specific areas. However please do not be alarmed when you see the word x-ray, as the levels of radiation used in a DEXA fat scan are nominal and much lower than those used in normal medical x-rays. Below is a table to reassure you:
Event Dose (microSv)
Full Body CT Scan 5000-15000
Specific Head CT Scan 2000-4000
X-Ray for Lumbar Region 600-1700
A 5 hour flight 35
Chest X-Ray 40-50
Daily amount of normal background radiation 6-8
DEXA - bone density assessment 11
DEXA* - whole body composition 1-4
The DEXA fat scan uses very small doses of ionizing radiation. Unlike a CT scan, a DERXA scan is two-dimensional, but its uniqueness comes from the fact that two beams of radiation are used in order to effectively establish the body’s composition. As you might understand, the denser the composition of material an x-ray beam encounters, the less energy will be absorbed, and it is through measuring the levels of absorption that an image can be created that can clearly identify what is bone, what is lean tissue, and what is fatty tissue.
Of course this is a very brief summary of the science behind a DEXA body scan, but it is meant to provide you with reassurance that a DEXA fat scan is a perfectly safe procedure. Of course with any procedure which involves any levels of radiation, a DEXA scan is not recommended for pregnant women. However with DEXA scans available in London, Manchester, Sidcup and Bury St Edmund's, we have much of England covered, so please do contact us if you would like to learn more about DEXA body scans.