What is a Dexa scan?

A DEXA (dual-energy X-ray absorptiometry) scan is an imaging test that uses X-ray technology to determine bone mineral content, fat mass, and lean body mass. It is considered a more accurate and insightful measure of body composition when compared to traditional scales or BMI calculations. In a DEXA scan, the patient lays on a bed, and a low-power X-ray scans across their body. The underlying principle is that denser materials, like bone, will block more of the X-rays and appear whiter on the scan, while less dense materials, like fat and organs (lean body mass), will allow more X-rays to pass through and appear in shades of gray. The scan provides valuable information about bone health, risks of osteoporosis, the proportion of visceral fat, and appendicular lean mass index. It's often used to track body composition changes over time and may be recommended annually for greater accuracy in health assessments 1 2.