Author
MILNE, DAVID - 5450-10-00 | |
Davis, Cindy | |
Klevay, Leslie | |
Nielsen, Forrest - Frosty |
Submitted to: Nutrition
Publication Type: Review Article Publication Acceptance Date: 2/13/2001 Publication Date: 9/1/2001 Citation: Nielsen, F.H., Milne, D.B., Davis, C.D. 2001. Low dietary zinc alters indices of copper function and status in postmenopausal women. Nutrition. 17(9):701-708. Interpretive Summary: The essentiality of zinc and copper for human health is well established. However, there is an antagonistic relationship between zinc and copper; very high amounts of zinc have been found to interfere with the uptake and use of copper. Because deficient copper may result in ischemic heart disease, a study was performed to determine the effect of a moderately high intake of zinc, in comparison with a low intake of zinc, on indicators of copper metabolism in postmenopausal women fed low (1 mg per day) and adequate copper (3 mg per day). The findings indicated that 1 mg of copper per day is not sufficient for maintaining copper status in postmenopausal women. The most surprising finding was that an inadequate intake of zinc (3 mg per day), not the moderately high intake of zinc (53 mg per day), was the dietary treatment that markedly exacerbated the changes in copper indices when dietary copper was low. The responses of the postmenopausal women indicated that inadequate dietary zinc resulted in a depression in copper absorption and the synthesis of some essential copper proteins. The responses also indicated that some copper status indicators might be useful for evaluating the zinc status of humans. The results from the study suggest that a combined inadequate intake of copper and zinc can result in changes (for example, increased blood cholesterol, heart beat changes, and a decrease in an important antioxidant enzyme) that could increase the susceptibility to an heart attack. Technical Abstract: The essentiality of zinc and copper for human health is well established. However, there is an antagonistic relationship between zinc and copper; very high amounts of zinc have been found to interfere with the uptake and use of copper. Because deficient copper may result in ischemic heart disease, a study was performed to determine the effect of a moderately high intake of zinc, in comparison with a low intake of zinc, on indicators of copper metabolism in postmenopausal women fed low (1 mg per day) and adequate copper (3 mg per day). The findings indicated that 1 mg of copper per day is not sufficient for maintaining copper status in postmenopausal women. The most surprising finding was that an inadequate intake of zinc (3 mg per day), not the moderately high intake of zinc (53 mg per day), was the dietary treatment that markedly exacerbated the changes in copper indices when dietary copper was low. The responses of the postmenopausal women indicated that inadequate dietary zinc resulted in a depression in copper absorption and the synthesis of some essential copper proteins. The responses also indicated that some copper status indicators might be useful for evaluating the zinc status of humans. The results from the study suggest that a combined inadequate intake of copper and zinc can result in changes (for example, increased blood cholesterol, heart beat changes, and a decrease in an important antioxidant enzyme) that could increase the susceptibility to an heart attack. |