The concept of oral tolerance induction to foods.

The conventional wisdom is that early exposure to allergenic food proteins during pregnancy, lactation, or infancy leads to food allergies, and that prevention strategies should therefore aim to eliminate allergenic food proteins during pregnancy, breastfeeding, and early childhood. Prolonged exclusive breastfeeding and delayed weaning onto solid foods is therefore seen as an effective public health policy to prevent allergies. However, there is little epidemiological data to support this belief. Interventional studies on dietary elimination have failed to reduce IgE-mediated food allergies. Conversely, there is preclinical data and some clinical data to suggest that early cutaneous exposure to food protein through inflamed skin leads to allergic sensitization and that early oral exposure results in the induction of tolerance. New strategies to prevent food allergy in infants need to be put to test in randomized controlled interventional studies.