Taste Acuity and Hair Zinc Concentrations in an Elderly Sample of Lubbock, Texas

Abstract

Objectives of this research were to evaluate and compare taste perception, hair zinc concentrations and dietary zinc intakes in elderly and young adults. Modified triangle tests were conducted on thirty-one elderly and thirty-one young adult volunteers to determine sweet, salty and bitter taste thresholds. Hair samples, diet histories and health information were collected during each personal interview. Hair samples were analyzed for zinc content using atomic absorption spectophotometry. Statistical treatment involved factorial analysis of variance and Spearman correlation coefficients.

Data indicated significant differences in tasting abilities between old and young subjects for sucrose (p<.01), sodium chloride (p < .005) and urea (p< .005). Increasing inability to recognize sucrose was demonstrated with advancing old age (p < .05). Dentures affected the elderly's ability to recognize urea (p< .05). Tobacco was insignificant for both groups. Hair zinc concentrations were lower for the elderly participants (p < .005), and were correlated with taste acuity (rho < .05). Seven per cent of the older sample were calculated to consume the 15 mg. RDA for zinc.

Recommendations implicated for the elderly are: consumption of a wide variety of foods and seasonings for increased palatability and zinc intakes, cautious use of low zinc meat alternates in institutional settings and an increased awareness by health professionals to the signs and symptoms of zinc deficiency.