Dietary zinc intake and zinc concentrations of plasma, erythrocytes, and breast milk in antepartum and postpartum lactating and nonlactating women: a longitudinal study

Abstract

The zinc status of a group of 23 lactating and 13 nonlactating women was assessed longitudinally from 37-wk gestation through 6 months postpartum. Dietary zinc intake was determined by chemical analysis of 3-day duplicate plate food composites. In addition, zinc concentrations were measured in plasma, erythrocytes, and breast milk. The mean dietary zinc intake of both groups of postpartum women as determined by direct analyses was 42% of the Recommended Dietary Allowances or less. The plasma and erythrocyte zinc concentrations were not significantly different between the lactating and nonlactating women. Plasma zinc concentration increased from the time of delivery to one month postpartum for both groups and did not significantly increase further through 6 months postpartum. Erythrocyte zinc decreased from delivery through 6 months postpartum for both groups. Breast milk zinc concentration decreased with the duration of lactation. The calculated zinc intake of infants from breast milk was less than 50% of the Recommended Dietary Allowances. There was no correlation of maternal dietary zinc intake or maternal plasma and erythrocyte zinc with the concentration of zinc in breast milk.

Effect of Iron Supplementation during Pregnancy on Trace Element (Cu, Se, Zn) Concentrations in Serum and Breast Milk from Nigerien Women

“…The changes of trace element concentrations observed in Nigérien women during gestation are in agree ment with those of previous studies in Europe [11][12][13], New Zealand [8] and India [14]. However, serum zinc at 6 months of gestation and at delivery are at the lower concentration of the range covered by published values both in developed [7,11,12,15,16] and develop ing countries [16][17][18]. Serum zinc alone is known to be a poor index of zinc status and it is therefore difficult to draw any definite con clusions.…”

“…The copper, selenium and zinc values ob tained in cord blood serum are within the range of previous reports in developed [12,13,15,26,27] or developing countries [18]. However, the iron status is at the lower range covered by published values [28][29][30], In ac cordance with previous reports, selenium and copper levels in cord blood serum were lower than those in maternal serum [13,18,24,26], whereas iron status and zinc concentration in umbilical serum were higher [15,18,26,[28][29][30], The mechanism of trace element trans port across the placenta is rather unclear.…”

Changes in Zinc and Copper Concentrations in Breast Milk and Blood of Japanese Women during Lactation.

“…The values continued to decrease until around 3 months of lactation, and main tained a constant level thereafter (Fig. 5 the world (30,(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45)(46)(47)(48)(49)(50). Concentrations of zinc and copper in colostrum were high and rapidly decreased in the first 2 to 3 weeks after parturition and then stabilized in the later days of lactation.…”

Human Milk: Nutritional Aspects of a Dynamic Food

“…Early milk contains an average of 4 mg/l of zinc; at 6 months the values are 1.1 and at 1 year 0.5 mg/l [30]. There is little convincing evidence that the maternal diet has an influence on milk concentrations of these elements [31,32]. The serum level of copper in nursing infants is more related to the concentration of ceruloplasmin that is low at birth than to the milk content.…”