ASSESSMENT OF COPPER NUTRITIONAL-STATUS

Despite increased interest in the role of copper deficiency in clinica l problems and an increased understanding of the physiological roles o f copper, the diagnosis of a marginal deficiency has not been perfecte d. The use of nonstandardized procedures and the effects of factors ot her than copper nutriture have impeded identification of the ''ideal'' indicator of copper nutritional status in adult humans. The specific activity of copper enzymes, or of copper-containing enzymes in blood c ells, such as erythrocyte superoxide dismutase and platelet or leukocy te cytochrome c oxidase, may be a better indicator of metabolically ac tive copper stores than the serum concentration of copper or cerulopla smin, because the enzyme activities are sensitive to changes in copper stores and are not as sensitive to factors not related to copper nutr iture. A single index, such as serum copper concentration, is inadequa te for assessing the total body copper nutriture of an individual and must be supported by corroborating evidence.