Assessment of zinc and copper status of healthy elderly people using metabolic balance studies and measurement of leucocyte concentrations

Abstract

Metabolic balance studies for zinc and copper were carried out in 24 apparently healthy elderly people aged 69.7 to 85.5 yrs, living in their own homes and eating self-selected diets. The zinc and copper concentrations in whole blood, plasma, and leucocytes were also measured. Mean daily intakes for zinc and copper were 137 and 20.1 μmol with mean retentions of 1.0 and -0.8 μmol, respectively. These values did not differ significantly from equilibrium (p < 0.01). For zinc and copper, respectively, mean concentrations were 11.0 and 19.4 μmol/l in plasma, 120 and 11.5 μmol/106 cells in leucocytes, and 99 and 13.4 μmol/l in whole blood. These data will provide normal standard values for elderly people in good health and should serve as a basis for the investigation of elderly people with suspected deficiencies of these trace metals.