QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Storey, M. L. Articles by Greger, J. L. Search for Related Content PubMed PubMed Citation Articles by Storey, M. L. Articles by Greger, J. L.

Iron, Zinc and Copper Interactions: Chronic versus Acute Responses of Rats¹

Department of Nutritional Sciences, University of Wisconsin, Madison, WI 53706

Several methodologies were evaluated to study iron, zinc and copper interactions. In three studies, rats were fed diets containing adequate levels of iron (33–35 µg Fe/g diet) and zinc (15–25 µg Zn/g diet) and diets with excessive levels of zinc (2441–2470 µg Zn/g diet) or iron (1408–3042 µg Fe/g diet). Consumption of excess iron for several weeks or in one test meal did not alter tissue levels of zinc or apparent absorption of ⁶⁵Zn. In contrast rats fed excess zinc throughout the three studies had depressed hematocrits and serum copper levels, apparently absorbed ⁵⁹Fe less efficiently and retained less ⁵⁹Fe in livers and tibias than control animals. Nutritional status with regard to iron or zinc, not just the intakes of iron and zinc, also influenced the interactions between zinc and iron. Rats fed excess iron for several weeks retained less ⁶⁵Zn from a test meal in their tibias than rats fed excessive iron in only the test meal. Although chronic ingestion of excess zinc depressed apparent absorption of ⁵⁹Fe from a test meal, the ingestion of one test meal with excess zinc did not. Investigators studying nutrient interactions should not rely solely on studies in which unadjusted humans or animals are given a single dose of test substances because acute responses do not reflect all the changes induced by chronic feeding.

KEY WORDS: • zinc • iron • copper • bioavailability • nutritional status

¹ This work was supported by the College of Agricultural and Life Sciences, University of Wisconsin-Madison Project No. 2623 and National Institutes of Health Training Grant No. 5T32CA09451.

Manuscript received 8 October 1986. Revision accepted 17 March 1987.