The researchers also tested for milk allergy using skin-prick testing, a standard food allergy test. Between eight and 15 months post-study, seven children had no reactions. Blood levels of milk IgE antibodies, which indicate allergy, slowly decreased, while IgG4, an antibody that indicates immunity to an allergen, rose.
The study authors also found that the prevalence of reactions continued to decline over time.
As part of the study, children and their parents kept daily logs of milk and dairy consumption and recorded symptoms, such as hives, abdominal pain, sneezing and cough. For the first three months, drinking milk triggered reactions nearly half of the time. During the next three months, milk triggered reactions 23 percent of the time, while some children reported no reactions.
Milk allergy is the most common food allergy. In those who are allergic, milk proteins cause the immune system to overreact, bringing a cascade of symptoms that can range from hives, itching, swelling and vomiting to anaphylaxis in the most severe cases.
Three million U.S. children have at least one food allergy, according to the U.S. Centers for Disease Control and Prevention.
The Food Allergy & Anaphylaxis Network has more on food allergies.
-- Jennifer Thomas
SOURCE: Johns Hopkins Children's Center, news release, Aug. 18, 2009
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