Diminished taste acuity may account for the persistence of
protein and caloric
malnutrition observed in a majority of
hemodialysis patients inspite of liberalization of the prescribed amount of
dietary protein. Twenty-two patients undergoing thrice weekly
hemodialysis for more than 6 months were tested for taste acuity and plasma
zinc concentration, after which a double-blind study was instituted using a
zinc supplement (50 mg of elemental
zinc as
zinc acetate per day) or a placebo. The threshold of taste detection and recognition for
salt (NaCl), sweet (
sucrose), and bitter (
urea) but not for sour (HCl) improved significantly in all patients on
zinc supplementation. None of these parameters improved in those taking placebo. During the study period, the mean plasma
zinc level increased from 75 +/- 8 to 97 +/- 10 microgram/dl (P less than 0.001) in patients receiving
zinc acetate. There was not significant change in plasma
zinc level in the placebo group (75 +/- 15 to 80 +/- 15). The results of this study show that uremic
hypogeusia improved in association with
zinc supplementation and elevation of plasma
zinc concentration.