Each morning, millions reach for a cup that quietly negotiates with their nervous system — a ritual so ordinary that its cardiovascular consequences often go unexamined. Caffeine, as cardiologist Dr. Motgi explains, is not merely a mental stimulant but a systemic one, rousing the body's ancient fight-or-flight machinery and, for some, crossing the line from alertness into alarm. The question of whether a racing heart is a benign side effect or a signal worth heeding is one that medicine now asks us to take seriously, not with fear, but with informed attention.