A quiet revolution is unfolding on wrists, fingers, chests, and nightstands around the world. Wearable health technology has evolved from simple step counters into sophisticated medical instruments capable of detecting atrial fibrillation, predicting blood glucose spikes, mapping brainwave patterns, and measuring visceral fat with clinical precision. What once required a hospital visit, a specialist referral, and thousands of dollars in testing now fits in your pocket, wraps around your finger, or slips under your mattress.