Copper nutrition during infancy and childhood.

Full-term human infants are believed to possess adequate copper stores to last through weaning regardless of the copper content of the diet they are fed. This may not be generally true, however; a combination of low copper intake and low bioavailability from the diet may lead to copper deficiency. More information is needed on the bioavailability of copper from different infant diets, but it appears that copper is well absorbed from breast milk compared with infant formula. Several dietary factors that may affect copper absorption in infants, such as protein sources, amino acids, phytate, ascorbic acid, and other essential cations, need to be evaluated further. Studies in human infants evaluating these factors through use of stable isotope methods, as well as better indicators of copper status, are needed before the copper requirements of infants can be established. This is particularly important for premature infants who, born with inadequate copper stores, are prone to develop copper deficiency unless given higher provisions of copper. The possibility of copper excess also needs to be considered because there are limited opportunities to diagnose copper toxicity. Finally, the role of homeostatic regulation of copper metabolism in infants needs to be evaluated.