Determinants of Copper Needs Across the Life Span

In the area of mineral supplements, the ODS cosponsored a workshop initiated by the Fogarty International Center and the University of Chile, Genetic and Environmental Determinants of Copper Metabolism, on March 18-20, 1996. This workshop was also cosponsored by the National Institute of Child Health and Human Development, the National Institute of Diabetes and Digestive and Kidney Diseases, the National Institute of Environmental Health Sciences, and the Environmental Protection Agency. The workshop brought together over 60 international scientists from academia, industry and governments who work in the area of copper metabolism, requirements, or toxicity. This group reviewed, from an international perspective, the recent significant advances in understanding of the molecular mechanisms underlying genetic disorders of copper metabolism and their implications for copper intake and exposure. One session of this workshop focused on the difficult question of how to adequately measure copper status in humans. The proceedings of this workshop have been recently published as a supplement to the American Journal of Clinical Nutrition.

Copper is a trace mineral that is part of several enzymes and proteins that are essential for adequate use of iron by the body. While frank hypocupremia is rarely seen in the US population, lower copper intake has been implicated with other variables such as heightened cholesterol in some studies as a possible risk factor for cardiovascular disease. Copper toxicity is rare in the US population. Due to the difficulty in measurement of copper status, the many factors such as zinc, carbohydrate and vitamin C intake that affect copper bioavailability, and the inability at that time to establish a requirement for copper, the Subcommittee on the Tenth Edition of the RDAs could not establish a RDA for copper and instead recommended a safe and adequate range of copper intake. While copper is viewed as a nutrient that is thus under effective homeostatic control in humans, adequate dietary supplementation with copper in relation to total parental nutrition, and in relation to nutrient-nutrient, hormone-nutrient and nutrient-pharmaceutical interactions remain important areas for study.

Most multivitamin dietary supplements on the market today include 2 mg of copper which is the midpoint of the Safe and Adequate Range of Intake recommended by the FNB. The conference on copper metabolism that was co-sponsored by the ODS further identified gaps in basic research related to copper metabolism and pointed to specific areas where research is needed related to copper requirements, copper-nutrient interactions, and specific disease endpoints with regard to dietary supplementation with copper.