Engineering Nutritional Profiles in Edible Insects Through Diet–Microbiome Interactions: Mechanisms, Applications and Future Directions

The growing demand for sustainable and nutritionally optimized protein sources has positioned edible insects as promising platforms for next-generation food and feed systems. Although insect composition varies with diet, the deliberate engineering of their nutritional profiles through controlled dietary and microbiome modulation remains insufficiently characterized. This review proposes an integrative framework in which edible insects are conceptualized as programmable biological systems whose biochemical composition can be tailored through diet–microbiome interactions. Current evidence is critically synthesized to elucidate how dietary inputs, including agro-industrial by-products and algal biomass, reshape gut microbial communities and metabolic pathways in key species such as Hermetia illucens, Tenebrio molitor, and Acheta domesticus. Emphasis is placed on engineering lipid metabolism and fatty acid composition because of their relevance to human nutrition, animal nutrition, and the development of functional food and feed products. By integrating insights from insect physiology, microbiology, and nutritional biochemistry, this work outlines strategies for precision feeding and microbiome-guided interventions aimed at optimizing insect-derived biomass. Key knowledge gaps and technical limitations are also identified, highlighting the need to transition from empirical approaches toward predictive, systems-based nutritional engineering. Collectively, this review highlights the transition from empirical feeding strategies toward predictive, systems-based approaches for designing customized insect biomass within sustainable circular bioeconomy frameworks.