COPPER INTAKE AND ASSESSMENT OF COPPER STATUS

Authors: Milne, David

Submitted to: The American Journal of Clinical Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/17/1998
Publication Date: N/A
Citation: N/A

Interpretive Summary: Copper is an essential nutrient that is important in maintaining a healthy heart and blood vessels. There is a need to know how much copper people need in order to make informed dietary recommendations. A series of 12 studies of the effects of diets that were low in copper in men and women, showed changes in some people when diets containing 1.0 milligram of copper or less per day were fed. About 20% of the people had an increase in the number of abnormal heartbeats and many showed changes in copper- containing proteins in blood cells when they ate less than one milligram of copper per day. These studies show that copper-containing proteins in blood cells are better for determining copper nutritional status in people than plasma copper. Also, at least 1.0 to 1.25 milligrams of copper are needed by adults to maintain good health. However, more than 2.6 milligrams of copper per day may be needed to recover from the effects of copper deficiency.

Technical Abstract: The diagnosis of marginal copper deficiency has not been perfected despite an increased understanding of the physiological roles of copper. The use of non-standardized procedures and the effects of factors other than copper nutriture have impeded identification of the "ideal" indicator of copper nutritional status in humans. A review of studies of experimental copper deprivation conducted with adult humans over the past 12 years has indicated that between 1.0 and 1.25 mg Cu/d is needed by adults for copper maintenance for periods of up to 6 months and 2.6 mg Cu/d, or less, for periods of up to 42 days is not sufficient for recovery from copper deprivation. Copper-containing enzymes in blood cells, such as erythrocyte superoxide dismutase and platelet cytochrome c oxidase, may be better indicators of metabolically active copper and copper stores than the plasma concentrations of copper or ceruloplasmin because the enzyme activities are sensitive to changes in copper stores and are not as sensitive to factors not related to copper nutriture.