Regulation of mineral metabolism from fetus to infant: metabolic studies.

Optimal mineral intake is crucial, especially during the period of rapid growth that occurs during infancy and childhood. Two minerals that have been found to play key roles during this period are iron and zinc. Supplementation studies have shown that these minerals have significant effects on birth weight as well as on weight and height increase during childhood. However, because a myriad of nutritional factors influence growth, it has often been difficult to characterize the role of any given mineral on fetal and early childhood growth. Stable iron and zinc isotopes can be used to study how the mineral status of iron- and zinc-deficient pregnant women affects their ability to absorb and transfer iron to the fetus. Furthermore, these isotopic tracers can be employed to examine the ability of infants to modify mineral absorption over time as the mineral stores of birth are depleted. Further studies using stable mineral isotopes during gestation, infancy and childhood will provide additional information on the regulation of mineral absorption and transport during these key periods of growth.