Longitudinal zinc balances in breast-fed and formula-fed infants

• Published in: Acta pædiatrica (Oslo) Vol. 81; no. 1; p. 1
• Main Authors: Sievers, E, Oldigs, H D, Dörner, K, Schaub, J
• Format: Journal Article
• Language: English
• Published: Norway 01.01.1992
• Subjects: Bottle Feeding; Breast Feeding; Diet; Female; Humans; Infant; Infant Nutritional Physiological Phenomena; Infant, Newborn; Longitudinal Studies; Male; Nutritional Requirements; Zinc - administration & dosage; Zinc - deficiency; Zinc - metabolism
• ISSN: 0803-5253
• DOI: 10.1111/j.1651-2227.1992.tb12068.x

Longitudinal zinc (Zn) balance studies were performed under domestic conditions in term breast-fed (n = 10), term formula-fed (n = 5; Zn concentration in the formula: 4 mg/l) and preterm formula-fed (n = 3) infants during the first 17 weeks of life. Samples of milk, urine and feces were analyzed by atomic absorption spectrometry. The median daily Zn intake in breast-fed infants decreased from 0.592 (0.457-0.829) mg Zn/kg body weight to 0.151 (0.095-0.304) mg Zn/kg body weight in the first 17 weeks of life; comparable values for bottle-fed term infants were 0.58 (0.511-0.701) and 0.674 (0.529-0.731) mg Zn/kg body weight. The median percent retention of Zn intake was 27 (-60 to 81.4)% in breast-fed infants and 21.5 (-42 to 64)% in formula-fed infants. In view of the urinary and fecal Zn losses measured, a daily intake of 0.3-0.5 mg Zn/kg body weight is considered to be sufficient to ensure a Zn retention equivalent to breast-fed infants. This requires a Zn concentration of 2-3 mg/l of Zn depending on milk volume intake.