Public health efforts were evident in the ancient world, but first acquired a scientific basis in the nineteenth century. The potential for evolutionary theory to improve public health interventions has only been recognized very recently. Evolutionary life history theory provides a unique theoretical framework, through its focus on competing functions subject to trade-offs over the allocation of energy. Originally these functions were considered to be “maintenance,” “growth,” and “reproduction,” however “defense” may be considered a fourth competing function as it reduces energy allocation to each of the three others. Recent research in humans provides experimental support for life history trade-offs in adults, with hormonal signaling implicated as a key regulatory mechanism. Observational studies have additionally identified diverse trade-offs during development, helping provide an evolutionary basis to the developmental origins of adult health and disease. Natural selection favors adaptive responses to environmental stimuli and stresses that maximize reproductive fitness rather than health.
