Jarrow Formulas® Lactoferrin (apolactoferrin) helps support the body's immune system and is found in breast milk, tears, and other bodily fluids.* This glycoprotein has an extraordinary capacity to bind iron (300 times that of serum transferrin) and thereby enhance the growth of beneficial bacteria.* Besides this, digestion of lactoferrin with gastric pepsin yields the powerful immune-supporting peptide lactoferricin B.*