Summary-The Early Feeds: Human Milk Versus Formula and Bovine Milk

[摘要] Adaptations of the gastrointestinal tract and the immune system that take place during the first year of postnatal life are of great importance, initially facilitating the transition between gestation and lactation, ultimately supporting independent postnatal life. When considering feeding options during the early periods, the roles of human milk, commercially prepared formula, and bovine milk must be evaluated in light of recent knowledge of these adaptations. Since infant feeding practices and the biologic capabilities of infants themselves vary significantly, the question arises as to what is "acceptable" v what is "optimal."NUTRITIONAL PROTEINSAt present, evaluations of the amount of protein required for infant growth are based on clinical studies of largē populations and include a "margin of safety" to meet the needs of the individual infant. Based on the assumption that the milk of a given species is best adapted to the nutrient requirements of the young of that species, human infant protein requirements are determined by the protein contribution of human breast milk.Breast-milk proteins are defined broadly as either whey or casein protein with an approximate ratio of 70:30, respectively. The casein portion is divided into three subgroups: α,β and κ casein. Whey proteins are divided into six major subgroups: α-lactalbumin, β-lactoglobulin; lactoferrin; serum-albumin; lysozyme, and immunoglobulins A, G, and M. Numerous nonprotein nitrogen substances including taurine exist as well.Protein AvailabilityProtein concentration of breast milk is approximately 1.2 g/dL when measured as total nitrogen. Nearly 25% of this is nonprotein nitrogen, much of which may not be used for nutritional purposes.

[学科分类] 儿科学