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Submitted to: Recommended Dietary Allowances Workshop
Publication Type: Abstract Only Publication Acceptance Date: 9/10/1995 Publication Date: N/A Citation: N/A Interpretive Summary: Technical Abstract: Over the past decade, there have been approximately 12 reported experiments on copper (Cu) deprivation, and/or interactions of Cu with other nutrients in adult humans. Cu intakes of these studies have ranged between 0.4-1.25 mg of Cu per d for periods of 36-165 d. These were alternated with or followed by intakes of 2.6 to 6.4 mg of Cu per d. Biochemical and physiological changes resulting from Cu deprivation were noted in many, but not all, subjects consuming less than 1.2 mg of Cu per d. These include changes in EKGs in 4 of 24 men receiving 1.02 mg of Cu per d and a high fructose diet after 77 d, 1 of 7 men fed 0.8 mg of Cu for 105 d, 3 of 6 men fed 0.6 mg of Cu for 49 d, and 3 of 13 postmenopausal women fed 0.57 mg Cu for 105 d. Plasma Cu was lowered with low Cu intake in only 4 of the 12 studies; it seemed to be related more to weight loss or fructose intake in two of these studies and was not as sensitive as Cu enzymes in blood cells to Cu status. Superoxide dismutase activity in erythrocytes (ESOD) and cytochrome c oxidase activity in platelets or mononucleated white cells seemed to be the most sensitive indicators to changes in Cu status. The apparent response to Cu deprivation, and presumably requirement, was affected by age, gender, carbohydrate source, dietary sulfur amino acid content, use of formula, and weight loss. Recovery from Cu deprivation, as indicated by recovery of ESOD was documented when 3 to 6.4 mg of Cu per d was fed for 30 d or more, but not when 2.6 mg or less was fed for up to 42 d. These studies indicate that at least 1.25 mg of Cu per d is needed for maintenance and that 2.6 mg of Cu per d, or less, for periods of up to 42 d is not sufficient for complete recovery from Cu deprivation. |
