Earlier this summer, I found myself lying flat on a padded table in Tucson, Arizona. A mechanical arm hovered above me, scanning my body from head to toe while I tried to remain still. Fifteen-ish minutes later, a clinician handed me a thick packet of results, which included details on bone density, lean muscle mass, body fat percentage, and color-coded visuals showing exactly where each of these metrics was located within my body. This was a DEXA scan, short for dual-energy x-ray absorptiometry. Since the late 1980s, hospitals have used this method to diagnose osteoporosis, and it remains the gold-standard test for bone health. In recent years, however, it has been rebranded as a wellness service, promoted by longevity influencers like Peter Attia and Bryan Johnson, and is now offered at boutique clinics and luxury retreats. At Canyon Ranch, where I was attending the Longevity8 program, the DEXA scan was presented as a crucial snapshot of what might be diminishing my healthspan. The appeal of the DEXA scan is clear. In a culture that is obsessed with optimization and biometric data, these scans promise hard numbers. But does all this information genuinely help you live longer, or does it simply provide expensive figures to obsess over? Your Body, Quantified Photograph: Boutayna Chokrane DEXA BD (bone density) scans were introduced into clinical practice in 1987 for measuring bone mineral density in the spine and hip. Current medical guidelines recommend that women over the age of 65, as well as younger women with risk factors, should be screened for osteoporosis. Though by this age, it’s often too late. “We suggest earlier screening, especially during periomenopause, when women can lose up to 20 percent of their bone mass,” says Jennifer Wagner, chief health and performance officer at Canyon Ranch. According to Wagner, the risks of osteoporotic fractures are high. “One in three women will experience one, and half of those have significant complications,” she says. “Prevention ideally starts 20 to 30 years before fracture risk peaks.” What catapulted DEXA into the wellness world is its ability to measure more than bone. A DEXA BC (body composition) scan can also distinguish fat from lean muscle, providing a clearer picture of cardiovascular risk, metabolic health, and stroke risk.