Experimental zinc depletion and altered taste perception for NaCl in young adult males

Taste perception for saltiness and bitterness was tested in five young men while fed a basal (15 mg Zn/day) and zinc depletion (0.25 mg Zn/day)) diet and in three young men during zinc repletion. The perceived intensity of five NaCl solutions ranging from 0 to 600 mM and five urea solutions also ranging from 0 to 600 mM were rated on a 17-point scale. The intensity ratings for the 75 and 150 mM NaCl solutions were significantly lower (p less than 0.05) during depletion than during the basal period; intensity ratings for 300 and 600 mM NaCl solutions did not change significantly. Bitterness perception was not altered with zinc depletion. The changes in perceived intensity that occurred were not related to parotid salivary zinc concentration, percentage change in plasma zinc with depletion, or the length of time required for depletion. The results suggest that zinc depletion may alter the taste perception of some moderately salty solutions.