Variations in trace element concentrations in breast milk with stages of lactation

The influence of stages of lactation on the mineral and trace element concentrations of breast milk collected from 20 healthy lactating women in a Nigeria population was investigated using instrumental neutron activation analysis (INAA) and proton induced X-ray emission (PIXE) analysis. The breast milk samples were divided into colostrum (day 1-5), transitional (day 6-13) and mature milk (day 14-28). The result of the study show that colostrum milk has a significantly higher mean concentration of Ca, Cl, Cu, Fe, Mg, Na and Zn than the transitional and mature milk. Furthermore, the mean concentrations of Fe, Mg, Na and Zn in transitional milk were found to be significantly higher when compared with the mature milk. It was also observed from the serni-log plot of the concentration of the elements against days of lactation that the concentration of all the elements decreased significantly throughout the lactation period studied with Cu, Fe and Zn concentration showing the greatest decline, particularly in the early stages of lactation.