Recent discussion on whether artificially mothers are passing on their allergies sent me searching for an obscure article I came across a few years ago. It was a review of a PhD thesis which studied the effects of drinking milk from another species on the immune and allergy status of mothers and their children. Dr Collins demonstrated that the antibodies produced by cows against the allergens that abound in their habitat (such as pollens, moulds and mites) survive to be present in the milk we buy, and also survive passage through the gut. He did not mention ABM, which is more processed. He postulated that when humans drink cow's milk they intercept these immunological messages from cow to calf and misread them, resulting in a disturbed immune response such as allergy. This may be more likely to happen in infancy when our immunological computer is being programmed. He studied rabbit consumption of mouse antibodies and found that 1) if you feed rabbits mouse antibodies directed against a specific antigen, the rabbits make anti-antibodies; 2) anti-antibodies cross the placenta; 3) anti-antibodies are found in the mother rabbit's milk; 4) the immune response of the offspring differs from that of the control rabbits in a way that suggests allergy. While human studies have not been done, Dr Collins was inspired by the lack of allergy he observed in Papua New Guinea where prolonged breastfeeding has been the norm for generations. Having anti-antibodies to allergens in your system is like having the allergens themselves. They encourage an antibody response then take up the binding sites. An allergy is basically a poorly regulated or inappropriate immune response. If all this is true, it means that mothers exposed to cow milk (is there a crucial age??) may be passing on their allergies through anti-antibodies via the placenta and breastfeeding. One can only hope that the cycle will be broken in a generation or two if we stick to human milk for human babies. Of course this is not the only allergy transfer mechanism. My 10yo has inherited his father's pollen allergy. They even started on the same day this year, despite being in different states. Maybe Kathy Auerbach was right about Australian men and nursing. Ros Escott B.App.Sc(OT), IBCLC