Insects survive starvation, heat, and infection by reallocating substrates while maintaining cellular protection and repair. These processes are usually treated separately, obscuring that the value of a metabolic response depends on tissue demand, timing, physiological state, and damage-control capacity. This article develops a non-empirical physiological framework in which survival depends on coordination rather than maximal fuel release or indiscriminate suppression of reactive oxygen species (ROS). Evidence from Drosophila and selected lepidopteran and hemipteran systems shows rapid nutritional-state remodeling, regulated carbohydrate and lipid mobilization, amino-acid recycling and acquisition responses, and context-dependent redox signaling. The same literature identifies failure modes: dysregulated mobilization can accompany poorer starvation survival, sustained immune-driven release can deplete reserves, and redox effects vary by tissue, life stage, age, sex, and stress protocol. The proposed architecture therefore separates fuel availability, mobilization control, tissue demand, redox signaling, oxidative damage, and repair capacity. It is intended as a testable organizing framework, not a validated universal mechanism.
