Association between zinc pool sizes and iron stores in premenopausal women without anaemia

Abstract

The simultaneous occurrence of Zn and Fe deficiencies in man has been known since the discovery of human Zn deficiency. However, it is not established that low Fe stores per se or Fe-deficiency anaemia infer low Zn status. Therefore our objective was to identify relationships between Zn and Fe status in premenopausal women without anaemia. We also examined the contribution of food frequencies and blood loss to Zn and Fe status. The subjects were thirty-three apparently healthy premenopausal women without anaemia, who were not taking dietary supplements containing Zn or Fe or oral contraceptives. Main outcomes were Zn kinetic parameters based on the three-compartment mammillary model and serum ferritin (SF) concentration; contributing factors were the frequency of consumption of specific foods and menorrhagia. Lower SF was significantly associated with smaller sizes of Zn pools. The breakpoint in the relationship between SF and the lesser peripheral Zn pool was found to be 21.0 microg SF/l. SF also correlated positively with frequency of beef consumption and negatively with bleeding through menstrual pads (BTMP). Similar to SF, the Zn pool sizes correlated positively with frequency of beef consumption, and negatively with BTMP. In summary, Zn pool sizes and Fe stores were highly correlated in premenopausal women. SF concentrations < 20 microg/l suggest an increased likelihood of low Zn status.