Jarrow Formulas® Lactoferrin (apolactoferrin) is an important immune supporting glycoprotein that is found in breast milk, tears and other body fluids.* One of the biological activities of lactoferrin comes from its powerful ability to bind iron (300 times that of serum transferrin), which promotes the growth of beneficial bacteria.* Moreover, digestion of lactoferrin by gastric pepsin liberates the immune-supporting peptide lactoferricin B.*