Zinc supplementation does not affect breast milk zinc in women with adequate zinc status. To evaluate if this is also true of settings where zinc deficiency is more prévalent, a randomized, double blind trial of zinc supplementation was conducted in a low-socioeconomic urban Indian setting where usual diet is low in zinc, and high in inhibitors of zinc absorption.Lactating women 0-2 mo and 4-6 mo postpartum were identified, and using a stratified randomization were allocated to receive zinc 20 mg daily in 2 doses (n = 50 0-2 mo, n = 51 4-6 mo) or control preparation (n=61 0-2 mo and n = 50 4-6 mo). A midfeeding 10 ml breast milk sample was collected before and after supplementation for 30 days. Median breast milk zinc concentrations (urnol/L) in first 6 months of lactation were 62.8, 32.2, 23.1. 16.3, 18.3, 18.5, respectively. Both in 0-2 months and 4-6 months strata the change in zinc levels was not significantly different beween zinc (Z) and control (C) groups (0-2 mo Z-18.9 4. 28.2, C-22.1±16.1; 4-6 mo Z-2.6±6.6, C 0-6 ± 9.5). Among women 0-2 mo postpartum with baseline level < 45.0 umol/l, the zinc supplementation group had caused a significantly less decrease in breast milk zinc (Z 1.4 ±. 19.5, C 9.7 ± 8.5, p = 0.05). The same was not true for women 4-6 mo postpartum. We conclude that in deficient populations, breast milk zinc concentrations are similar to adequately nourished populations, with a high individual variability. Zinc supplementation affected breast milk levels in early lactation, in a subgroup with low breast milk zinc concentrations.
|Original language||English (US)|
|State||Published - Dec 1 1996|
ASJC Scopus subject areas
- Molecular Biology