Bioavailability of copper.

Copper intakes of infants and adults are often much lower than current recommendations. Copper status, however, appears adequate in most populations. This suggests that copper requirements may be lower than believed earlier, except those for premature infants, who have high requirements as a result of low prenatal stores. Infants, in general, constitute a risk group because milk is low in copper. Bioavailability of copper from human milk is high, whereas it is lower from cow milk and infant formula. Protein source, amino acids, carbohydrates, and ascorbic acid can affect copper availability, whereas phytate, zinc, and iron appear to have little influence on copper absorption, at least physiologic intakes.