A large prospective study has found that adults over 40 who follow a particular breakfast pattern face a 29% higher risk of death — a finding that quietly repositions an old question: not merely what we eat, but when. Drawing on the NutriNet-Santé cohort, researchers have begun to map the body as a time-sensitive system, one whose metabolic rhythms can be honored or violated with lasting consequence. The emerging science of circadian eating suggests that the clock on the wall and the clock inside the body are in constant negotiation — and that ignoring one may cost us the other.