Submitted to: The American Journal of Clinical Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/2/2001
Publication Date: 9/20/2002
Citation: OLIVARES, M., LONNERDAL, B., ABRAMS, S.A., PIZARRO, F., UAUY, R. AGE AND COPPER INTAKE DO NOT AFFECT COPPER ABSORPTION, MEASURED WITH THE USE OF 65CU AS A TRACER, IN YOUNG INFANTS 1-3. AMERICAN JOURNAL OF CLINICAL NUTRITION. 2002. v. 76(3). p. 641-645.
Interpretive Summary: A considerable amount of copper is transferred from the mother to the fetus. Copper is accumulated in the fetus mainly at the end of the gestation period, and a substantial portion of the accumulated copper is retained in the liver of the fetus. The substantial stores of copper in the liver of the term fetus may aid in preventing copper deficiency during the early months of life. Copper homeostasis is believed to involve changes in both intestinal absorption and biliary excretion. The answer to the question of how well controlled copper absorption is in the first months of life is crucial to determine whether normal infants are at risk of copper excess within the range of acceptable intakes. The aim of this study was to evaluate copper absorption in infants during the first 3 mo of life and the effects of age and copper intake on copper absorption.
Technical Abstract: Copper homeostasis involves a high degree of regulation in which changes in absorption and biliary excretion are the main mechanisms. Whether neonates and small infants can make these changes efficiently is unknown. We evaluated the effect of age and copper intake on copper absorption in infants during the first 3 mo of life. Thirty-nine healthy infants (19 infants aged 1 mo and 20 infants aged 3 mo) were selected. One-half of the subjects were randomly assigned to receive oral supplementation of 80 mg Cu (as copper sulfate) · kg body wt-1 · d-1 for 15 d. At the end of the trial, copper absorption was measured by using orally administered 65Cu as a tracer and fecal monitoring of recovered 65Cu. Mean (± SD) copper absorption at 1 mo of age was 83.6 ± 5.8% and 74.8 ± 9.1% for the unsupplemented and supplemented infants, respectively. The corresponding figures at 3 mo of age were 77.6 ± 15.2% and 77.7 ± 11.3%. A two-way analysis of variance showed that age, copper supplementation, and the interaction between age and copper supplementation did not have a significant effect on copper absorption. There was an inverse correlation between total fecal copper and the percentage of 65Cu absorption (r = -0.50, P < 0.003). Copper absorption in young infants is high but does not respond to copper intake within the range tested.