Microwaving cuts benefits of breast milk

Microwaving breast milk to warm it reduces immune-boostingproperties that benefit babies, new research confirms.

Doctors at Stanford University in California found thatmicrowaving the milk markedly decreased the effectiveness of twosubstances that defend against infectious organisms.

The new study, published in the April issue of the journalPediatrics, found that microwaving decreased activity of enzymescalled lysozymes and antibodies called IgA, said researcher John A.Kerner.

The researchers studied microwaved milk in an intensive-carenursery, where mothers' milk is used to feed their premature infants,who are susceptible to infection.

The first milk produced by a nursing mother, called colostrum,is especially rich in nutrients and is thought to immunize babiesagainst diarrhea and other illnesses.

The American Academy of Pediatrics recommends againstmicrowaving milk because it can overheat the milk in the middle ofthe bottle and scald the baby.

Any other method is preferable, said Vergie Hughes, nursingcoordinator of the National Capital Lactation Center at GeorgetownUniversity Hospital in Washington, D.C.

"Mothers can set the bottle in a pan of tepid water," she said.Georgetown has recommended against microwaving milk since 1989, whena study found that microwaving decreased immune factors, Hughes said.

Breast milk does not have to be heated at all, she said. "Roomtemperature is fine - babies will do fine with cool beverages."

Nutrients may be lost when milk is heated by any method, shesaid.

Recent surveys have found that, despite the benefits,breast-feeding declined dramatically in the United States in the late1980s, especially among lower-income women.