Trace element compositional changes in human milk during the first four months of lactation.

The aims of this paper were to evaluate changes in specific oligoelements in human milk during the first four months of lactation and to correlate such changes with total antioxidant status (TAS) and other parameters, such as the mother's age, primipara versus multipara, and supplement intake. Milk samples were collected from 31 lactating women following 1, 4, 8, 12 and 16 weeks after birth. Trace levels of 13 elements were measured by inductively coupled plasma-mass spectrometry (ICP-MS). The results obtained for the oligoelements exhibited a decrease in concentration from 7 days to 4 months of breast-feeding, with exceptions. Correlations were found between TAS and Co, V, Rb and Tl. Between primipara and multipara, differences were found for Ni and Rb. Regarding the mother's age, correlation was found for Rb and Ba (increased for mothers older than 30 years). Increased amounts of Rb, Mo and Tl at any lactation period appeared in women who took supplements.