Academy of Breastfeeding Medicine founder's lecture 2008: breastfeeding--an extrauterine link between mother and child.

In addition to a near-optimal combination of nutrients for the growing infant, breastmilk contains a wide array of bioactive molecules that are known to protect the infant against infectious disease and modulate the composition of the indigenous intestinal microbiota. A growing number of factors that modulate the infant's immunophysiology have also been identified in breastmilk. We suggest that this early immunomodulation via breastmilk is vital for infant health and may explain the epidemiological data indicating that breastmilk reduces the risk of immunoinflammatory conditions in infancy and also later in life. The body of scientific data regarding the role of transforming growth factor-beta in breastmilk in enhancing healthy immune maturation and reducing the risk of disease is reviewed in this article.