Sleep and dietary behavior are deeply conserved biological processes that co-evolved under ecological pressures shaping human anatomy, metabolism, immunity, cognition, and life history strategies. Major transitions in human dietary ecology, including plant-dominant hominin foraging, increased meat consumption, control of fire and cooking, agricultural domestication, industrialization, and postindustrial globalization, restructured nutrient intake, pathogen exposure, microbial ecology, metabolic demands, and temporal organization of behavior. Emerging evidence from evolutionary genomics, chronobiology, neuroendocrinology, and microbiome science indicates that sleep-feeding interactions represent a conserved adaptive regulatory module optimized for fluctuating energy availability and strong photoperiodic entrainment. Modern environments characterized by widespread availability of highly palatable, energy-dense foods rich in refined carbohydrates, added sugars, and multiple industrial additives, together with artificial light at night, continuous caloric access, sedentary behavior, and psychosocial stress produce a profound evolutionary mismatch destabilizing circadian-metabolic homeostasis. This mismatch is characterized by circadian disruption, temporal misalignment of feeding and sleep behaviors, and, in many populations, insufficient sleep duration. Within this conceptual landscape, the emerging framework of "evolutionary chrononutrition" proposes that metabolic health and sleep integrity depend not only on what humans eat, but critically on when food is consumed in relation to endogenous circadian architecture shaped across deep evolutionary time. This review synthesizes anthropological, physiological, and molecular evidence to develop an integrative evolutionary framework linking sleep and diet to contemporary cardiometabolic, neurodegenerative, inflammatory, and psychiatric disorders, with particular emphasis on how each major dietary transition plausibly altered sleep duration, architecture, circadian timing, neuroendocrine regulation, and the temporal alignment between feeding behavior and biological rhythms.
