British Journal of Nutrition

Full Papers

Taste acuity in response to zinc supplementation in older Europeans

Barbara J. Stewart-Knoxa1 c1, Ellen E.A. Simpsona1a2, Heather Parra1, Gordon Raea2, Angela Politoa3, Federica Intorrea3, Maud Andriollo Sancheza4, Natalie Meuniera5, Jacqueline M. O'Connora1, Giuseppe Maiania3, Charles Coudraya5 and J. J. Straina1

a1 Northern Ireland Centre for Food and Health, University of Ulster, Coleraine BT52 1SA, UK

a2 School of Psychology, University of Ulster, Coleraine, UK

a3 National Institute for Food and Nutrition Research, INRAN, Rome, Italy

a4 Laboratoire de Nutrition Vieillissement et Maladies Cardiovasculaires (NVMC), Faculté de Pharmacie, Université de Joseph Fourier, Grenoble, France

a5 Centre de Recherche en Nutrition Humaine d'Auvergne, Unité des Maladies Métaboliques et Micronutrients, INRA, Clermont-Ferrand/Theix, France

Abstract

Taste acuity declines with age and may be dependent upon Zn status. The aim of the present double-blind, randomised controlled intervention trial has been to determine taste acuity in response to Zn supplementation (placebo, or 15 or 30 mg Zn/d). Healthy older European adults aged 70–87 years were recruited within Italy (Rome) (n 108) and France (Grenoble) (n 91) to the European Commission-funded Zenith project. A signal detection theory approach was adopted for taste assessment. The data were converted to R indices and analysed by repeated-measures ANOVA controlling for baseline taste acuity as well as serum and erythrocyte Zn. Serum Zn increased post-intervention, indicating compliance with the intervention. Results differed across geographical region. Salt taste acuity was greater in response to Zn (30 mg) than placebo post-intervention among those recruited in Grenoble. There was no apparent change in acuity for sweet, sour or bitter taste in response to Zn. Supplemented Zn may have potential to enhance salt taste acuity in those over the age of 70 years. Further research is required to determine if enhanced salt taste acuity is reflected in the eating experiences of older individuals.

(Received September 05 2006)

(Revised May 29 2007)

(Accepted May 31 2007)

Correspondence:

c1 Corresponding author: Dr Barbara Stewart-Knox, fax +44 28 70324965, email B.knox@ulster.ac.uk