Daily selenium intake by breast-fed infants and the selenium concentration in the milk of lactating women in western Poland.

BACKGROUND

Human milk is the only natural source of food for infants during the first several months of life. The milk should contain all trace elements in adequate amounts, including selenium (Se). Se is of particular interest because the daily requirement for this element in infants is higher due to their rapid growth. The aim of our study was to determine the Se concentration in human milk and to calculate the daily Se intake by breast-fed infants in western Poland.

MATERIAL AND METHODS

The Se concentration was assayed in mature human milk (14 to 58 days after parturition) collected from 352 lactating women living in 7 voivodeships in western Poland. The concentration of Se was measured by the fluorometric method with 2,3-diaminonaphthalene as a complexing reagent. The values were expressed as ng/ml.

RESULTS

No significant differences were observed in terms of Se concentration among the milk samples collected from the different voivodeships. However, the highest values were obtained in the northern part of the region. The mean Se concentration was 10.51 +/- 2.76 ng/ml (range: 10.41-10.65 ng/ml). The calculated mean daily Se intake by breast-fed infants was 7.71 microg/day (range: 3.67-17.17 microg/day).

CONCLUSIONS

The Se concentration in human milk in the region studied here is uniform, but the daily Se intake of breast-fed infants in the western part of Poland is lower than the recommended daily requirement. The reason for this situation would appear to be low Se content in the soil, and consequently in the foodstuffs from this region.