Ferric pyrophosphate in precision iron fortification: mechanistic insights into food-system suitability, bioavailability modulation, and evaluation strategies.

Iron is an essential trace nutrient, and iron deficiency remains a major global public health problem. Iron-fortified foods are important vehicles for preventive iron supplementation. Precision iron fortification requires matching iron sources to specific food matrices to balance product quality and fortification efficacy. Ferric pyrophosphate (FePP) shows good food-system stability and gastrointestinal tolerability, but low solubility and limited bioavailability restrict wider application. This review addresses FePP food-system suitability, bioavailability modulation, and evaluation strategies, summarizing physicochemical modification, delivery systems, and absorption-oriented dietary modulation. These approaches improve dispersion and dissolution, control gastrointestinal release and transport, and mediate nutrient effects on Fe3+ reduction, complexation, and precipitation. FePP modulation should balance bioavailability and food quality through multilevel evaluation integrating in vitro, cellular, animal, and human studies. Future work should better match modulation technologies to food systems, optimize precision iron fortification, and advance practical FePP application.