The effect of exclusive breast feeding in the first few weeks after birth on infant morbidity due to infectious and allergic disorders was investigated in three separate prospective studies. In a rural community in India, breast-fed infants had a significantly lower incidence of respiratory infection, otitis, diarrhoea, dehydration and pneumonia. In an urban population in Canada, breast feeding was associated with a marked decrease in the occurrence of otitis and respiratory disease and to a lesser extent of diarrhoea and dehydration. In newborn siblings of children with atopic disease exclusively breast-fed for a minimum of six weeks, the incidence of eczema, recurrent wheezing, elevated serum IgE-antibodies to cow's milk, complement activation in vivo after milk challenge and hemagglutinating antibodies to beta-lactoglobulin was significantly lower compared with formula-fed matched group. These observations provide clinical data attesting the immunologic advantages of human milk.
PIP: 3 separate prospective controlled studies in India and Canada were conducted to determine the immunologic benefits of breastfeeding. In the Indian rural study, 35 newborn infants breastfed exclusively for at least the first 2 months of life were studied (average duration of breastfeeding, 4.8 months; range, 2.2-8.5 months), along with 35 bottlefed controls (using fresh cow's or buffalo's milk) matched as to socioeconomic status, parental education, occupation and family size. In the Canadian urban study, 30 breastfed neonates (average duration of breastfeeding, 3 to 6 months, range 2.5-5.8 months) and 30 matched bottlefed controls were similarly studied. The third study consisted of 37 infants exclusively breastfed for the first 6 weeks of life or longer; these infants had older siblings diagnosed as having an atopic disease. The controls consisted of 37 bottlefed infants who also had an older sibling with an allergic disease. In both the Indian and Canadian studies, all breastfed infants had significantly lower incidence of respiratory and diarrheal diseases and of complications such as pneumonia and dehydration (p0.001 in the Indian study; in the Canadian study, p.001 for respiratory infection and otitis media, p0.01 for diarrhea and p0.1 for dehydration) compared with bottlefed infants. In the study of infants with family history of atopy, breastfed infants had a marked reduction in the incidence of clinical atopic eczema and of recurrent allergic wheezing. High levels of serum IgE were seen in a large number of bottlefed infants, as were eosinophilia; IgE antibodies to cow's milk protein (40% of bottlefed babies); hemagglutinating antibodies (84%), and; complement activation in vivo after milk challenge. These findings support the claim that breastmilk provides immunologic benefits to the infant. They also show that 6 weeks of exclusive breastfeeding is effective in reducing the possibility of hypersensitivity and the incidence of manifest allergic disease in susceptible infants.