Effect of Zinc Toxicity on Calcium, Phosphorus and Magnesium Metabolism of Young Rats

Abstract
The effects of high levels of dietary zinc on bone mineralization, on growth and on the metabolism of calcium, phosphorus and magnesium of young male rats in the presence and absence of several dietary supplements were studied in a series of experiments. Zinc toxicity resulted in marked decreases in bone calcium and phosphorus levels and marked increases in bone zinc levels at the end of the first week animals were on experiment. Significant decreases in weight gain associated with zinc toxicity did not occur until the second week. Bone magnesium levels were not affected by zinc toxicity. Supplements of calcium and phosphorus alleviated the adverse effects of zinc on weight gain and on the deposition of calcium and phosphorus in the bone. Calcium and phosphorus supplements prevented the marked accumulation of zinc in the bones of young rats fed high levels of zinc. Zinc toxicity resulted in highly significant decreases in the retentions of calcium, phosphorus and magnesium by young rats which occurred at the end of the first week the animals were on experiment.