researchers have long hailed breast milk for its ability to boost an infant's immune system. Now, a new study led by Johns Hopkins researchers provides further evidence of this after discovering how breast milk can protect against a severe intestinal disease that affects preterm babies.

Dr. David Hackam, pediatric surgeon-in-chief at Johns Hopkins Medicine in Baltimore, MD, and colleagues found that a protein in animal and human breast milk - called epidermal growth factor (EGF) - staved off necrotizing enterocolitis (NEC) in preterm mice.

"We have known for some time that breast milk can protect premature babies against intestinal damage but how and why it did so has been somewhat of a mystery," says Dr. Hackam. "We believe that our findings solve a major piece of the mystery of this disorder."The researchers publish their findings in the journalMucosal Immunology.