Lactoferrin is a protein in human milk, animal milk, and other bodily fluids. Colostrum, the first milk made after a baby is born, is higher in lactoferrin.

Lactoferrin helps regulate how well iron is absorbed into the body from the intestine. It also seems to protect against infections from bacteria, viruses, and fungi. The lactoferrin in breastmilk is thought to help protect breast-fed infants against infections.

People commonly use lactoferrin for low iron levels during pregnancy and for preventing blood infections (sepsis) in premature infants. It is also used for diarrhea, common cold, and many other conditions.