title: Electrolyte composition of human breast milk beyond the early postpartum period.
abstract: The electrolyte composition of breast milk beyond 6 months postpartum has not been extensively examined, particularly chloride concentrations. A total of 140 samples of breast milk from 30 breast-feeding mothers were collected and analyzed. Mean mother's values +/- standard error of sodium (141 +/- 17 mg/L), potassium (480 +/- 11 mg/L), and chloride (452 +/- 32 mg/L) were found to be stable after 4 months postpartum until weaning commenced. Considerable variability was found for each constituent, equally divided between intra-individual and inter-individual for chloride and potassium, and predominantly intra-individual for sodium and lactose. In light of reported nutritional deficiency states involving electrolytes in exclusively breast-fed infants, it is possible that the variability of breast milk electrolyte concentrations may adversely affect infant nutrition in selected cases of older exclusively breast-fed infants.
authors.affiliation: Wyeth Nutritionals International, Philadelphia, Pennsylvania, USA.
authors.forename: R P
authors.initials: RP
authors.lastname: Wack
authors.forename: E L
authors.initials: EL
authors.lastname: Lien
authors.forename: D
authors.initials: D
authors.lastname: Taft
authors.forename: J D
authors.initials: JD
authors.lastname: Roscelli
mesh_terms: D002712:Chlorides / Q000032:analysis* / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005260:Female; D006801:Humans; D007227:Infant Nutritional Physiological Phenomena; D007231:Infant, Newborn; D007785:Lactose / Q000032:analysis / Q000378:metabolism; D008895:Milk, Human / Q000737:chemistry* / Q000378:metabolism; D049590:Postpartum Period / Q000378:metabolism* / Q000502:physiology; D011188:Potassium / Q000032:analysis* / Q000378:metabolism; D012044:Regression Analysis; D012964:Sodium / Q000032:analysis* / Q000378:metabolism; D013053:Spectrophotometry
chemical_list: D002712:Chlorides; D012964:Sodium; D007785:Lactose; D011188:Potassium