Abstract: Iron is an essential trace element for human growth and development, playing a critical role in the body. However, iron absorption is subject to interference from various factors. Iron deficiency anemia, caused by insufficient iron intake or malabsorption, is a serious threat to both physical and mental health. Currently, iron fortification is the primary method for supplementing iron in the body. This review begins with the absorption mechanism of iron, factors affecting iron absorption, and current iron fortification strategies, focusing on the chelation mechanisms and influencing factors of the third-generation iron supplement polysaccharide-iron complexes as well as the absorption mechanisms of these complexes. It also explores how structural modifications of polysaccharides could enhance the iron bioavailability and other properties of the complexes, aiming to provide a theoretical reference for improving the efficacy of polysaccharide-iron complexes in iron supplementation.

Key words: iron fortification; iron absorption; polysaccharide-iron complex; polysaccharide structural modification