Milk may be a treatment for milk allergy. In a carefully controlled study, researchers from Johns Hopkins Children's Center and Duke University found that giving milk-allergic children milk in increasingly higher doses over time eased their allergic reactions to milk and even helped some of the children completely overcome their milk allergy.

The findings suggest that giving milk-allergic children milk "gradually retrains the immune system to completely disregard or to better tolerate the allergens in milk that previously caused allergic reactions," Dr. Robert Wood, senior investigator on the study and director of Allergy & Immunology at Hopkins Children's in Baltimore, noted in a statement.

"These results suggest that oral immunotherapy may be the closest thing yet to a 'true' treatment for food allergy," Wood added.

He and colleagues caution, however, that much more study is needed and they advise parents and caregivers not to try giving milk to children who are allergic to it without medical supervision.

The study involved 19 children, ages 6 to 17 years, with severe and persistent milk allergy. Over 4 months, 12 children received escalating doses of milk powder by mouth, whereas 7 received a placebo powder that was identical in appearance and taste to the real milk powder.

The findings of the study are reported in the Journal of Allergy & Clinical Immunology.

At the beginning of the study, the children could tolerate only about a quarter of a teaspoon of milk, or about .04 ounces, on average. At the end of the 4-month study, both groups were given milk powder as a "challenge" to see what dose would cause an allergic reaction after the treatment.

The researchers found that children who had been receiving increasingly higher doses of real milk powder were able to tolerate an average of about 5 ounces of milk without an allergic reaction or only mild symptoms, such as itching in the mouth and minor stomach ache.

Placebo-treated children, on the other hand, were still unable to tolerate more than about a quarter teaspoon of milk without having an allergic reaction.

Milk tolerance in children treated with real milk powder continued to build over time, the researchers say. What's unclear, at the moment, is whether the children will maintain their tolerance to milk once they stopped consuming milk regularly.

"It may very well be that this tolerance is lost once the immune system is no longer exposed to the allergen daily," Wood said.

Milk allergy is the most prevalent type of food allergy and "we urgently need therapies that go beyond strict food avoidance or waiting for the child to outgrow the allergy," Wood said.