ESSENTIAL ELEMENTS IN MATURE HUMAN MILK

Human milk is recognised as the best source of essential elements for the infant in the first months of life. The objective of research was to determine the content of calcium, iron, magnesium, potassium and selenium in mature human milk. To evaluate possible relation with maternal (age, parity, breastfeeding pattern, dietary intake) and infant's (age, birth weight, sex) attributes. In the study participated 65 lactating women from Latvia (at least one month postpartum). Elements' content in human milk was analysed using ICP-MS (Agilent 7700x, Japan). Dietary data (72-hour food diary) were evaluated using the Fineli Food Composition Database (https://fineli.fi). Data analysis were carried out using IBM SPSS Statistics, version 22.0. Spearman's correlation, partial correlation and Mann-Whitney U test were used to evaluate how maternal & infant characteristics influence essential elements' content in human milk. Average content for calcium, magnesium and potassium in human milk was 28.40 +/- 7.06, 3.85 +/- 0.64 and 59.60 +/- 8.29 mg 100 mL(-1), respectively. Iron content in 97% of samples (n=63) was below detection limit (<0.10 mg 100 mL(-1)). Selenium content in all samples was below detection limit (<0.002 mg 100 mL(-1)). Calcium content in human milk was affected by breastfeeding pattern - average content of 30.51 +/- 7.31 mg 100 mL(-1) for exclusive breastfeeding and 25.41 +/- 5.43 mg 100 mL(-1) for partial breastfeeding, p=0.003. Dietary intake of essential elements among participants was within recommendations. Our obtained values for calcium, magnesium and potassium in human milk were in accordance with other studies. Further evaluation should be done for the optimisation of the ICP-MS method for the detection of iron and selenium in human milk.