Kefir is a fermented milk product, much similar to yoghurt, that originates from East Europe. According to a new study conducted on mice, kefir may help prevent the onset of food allergies by inhibiting the allergen specific antibody, Immunoglobulin E (IgE).

Consumption of milk kefir and soymilk kefir suppressed the IgE and IgG1 responses and altered the intestinal microflora in our supplemented group, suggesting that milk kefir and soymilk kefir may be considered among the more promising food components in terms of preventing food allergy and enhancement of mucosal resistance to gastrointestinal pathogen infection.

Of course, human trials will have to be conducted to confirm if kefir indeed have such effects. One aspect I am concerned about is the alcoholic content of traditionally prepared kefir. It might be alright for adults, but I don't think alcohol has any place in an infant's or child's diet.