Lactoferrin is a 77kDa glycoprotein and member of the transferrin family, a group of proteins capable of binding and transferring Fe3+ ions. Lactoferrin was first isolated from bovine milk and was demonstrated in human milk in 1960. Lactoferrin consists of a single chain polypeptide of about 700 amino acids.

The sequence homology between human lactoferrin and bovine lactoferrin is nearly 70%. Lactoferrin is considered to be part of the innate immune system and due to its strategic position on the mucosal surface of mammary glands it represents a first anti-microbial and anti-viral defense system. Bacteria require iron for growth and lactoferrin can inhibit bacteria by chelating iron. Next to this antimicrobial activity lactoferrin is reported to be an antioxidant that may support the proliferation, differentiation and activation of immune cells and strengthen the immune response. Lactoferrin is found in mucosal secretions, urine and plasma. The highest concentration of human lactoferrin is found in milk and colostrum.

In 2012 the European Food Safety Authority approved bovine lactoferrin as novel food ingredient. As healthy supplement it was used in many food matrices. The main use of bovine lactoferrin nowadays is the application in baby and infant powder milk, especially in China.