Concentration and distribution pattern of selected micronutrients in preterm and term milk from urban Brazilian mothers during early lactation
Trugo, N.M.; Donangelo, C.M.; Koury, J.C.; Silva, M.I.; Freitas, L.A.
European Journal of Clinical Nutrition 42(6): 497-507
1988
ISSN/ISBN: 0954-3007 PMID: 3409858 Document Number: 369662
The study was made to assess the concentration and binding pattern of zinc, iron, folate and vitamin B-12 in milk of Brazilian women of low socioeconomic status giving birth at term or preterm, during early lactation. Protein, fat, total solids and ash concentrations were also estimated. Protein and Zn concentrations decreased significantly as lactation proceeded whereas milk fat and folate increased with the lactation period. Total solids, ash, Fe and vitamin B-12 were unchanged. Zn was present mainly in the whey fraction while less than half of the total Fe was present in this fraction, with no significant change due to stage of lactation. Unsaturated folate and vitamin B-12 binding capacities and percentage of saturation of the folate-binding protein increased with the stage of lactation. The vitamin B-12 binding protein was highly unsaturated in all samples. There was no significant difference between term and preterm samples in the values studied. There were significant relations between total solids and fat, total Zn and whey Zn, folate and total folate-binding capacity, unsaturated and total folate-binding capacity, and unsaturated and total vitamin B-12-binding capacity.