A mother's diet can protect nursing newborns against food allergies. In mice, milk from mothers exposed to egg protein gave protection against egg allergy to the mothers and offspring, but also to fostered newborns whose birth mothers had not received egg. Newborns gained an insignificant degree of protection from mothers who were exposed to egg during pregnancy but did not breastfeed them. The protective effect was strongest when the newborns were born to and nursed by mothers who were exposed to egg before and during pregnancy and breastfeeding.
Pregnant and breastfeeding mothers were sometimes cautioned against consuming foods that commonly cause allergy, such as milk, egg, peanut, tree nuts, soy, wheat, fish and shellfish. More recently, feeding peanut foods to infants at high risk for peanut allergy was shown to decrease, not increase, the babies' likelihood of developing allergy to peanut. Allergists now recommend that, unless mothers already have diagnosed food allergies, they should not avoid allergenic foods while pregnant and nursing. Mothers are free to eat a healthy and diverse diet throughout pregnancy and while breastfeeding. Eating a range of nutritious foods during pregnancy and breastfeeding will not promote food allergies in developing babies, and may protect them from food allergy.
Maternal and early childhood diets do not cause food allergies in children. Most children do not develop food allergies, regardless of how they are fed., while some children develop allergies even when fed an optimal diet. The food allergy protections described in the study are dependent on specific proteins, some provided by the mother, others by the offspring. By identifying these proteins and proposing a mechanism through which mother and offspring contribute to the development of food tolerance in the newborn mouse, the research opens new opportunities to study how the protections break down in the case of food allergy and how such breakdowns might be prevented.
Preventing food allergy is critical because there are no approved treatments for this serious and potentially life-threatening condition. The mouse study found that when a nursing mother is exposed to a food protein, her milk contains complexes of the food protein combined with her antibodies, which are transferred to the offspring through breastfeeding. Aided by a protein in the offspring's gut lining and some immune cells, the food protein-antibody complexes are taken up and introduced to the offspring's developing immune system, triggering the production of protective cells that suppress allergic reactions to the food. These protective cells persist after antibodies from the mother are gone, promoting long-term tolerance to the food. A similar mechanism may offer protection to human infants.
haleplushearty.blogspot.com
