Taste acuity in response to zinc supplementation in older Europeans

Northern Ireland Centre for Food and Health, University of Ulster, Coleraine BT52 1SA, UK.
British Journal Of Nutrition (Impact Factor: 3.45). 02/2008; 99(1):129-36. DOI: 10.1017/S0007114507781485
Source: PubMed


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.

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Available from: Barbara Stewart-Knox, Dec 27, 2015
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    • "As micronutrient deficiencies arise, decreased energy and motivation can further compromise dietary quality in a pathological cycle. For example, dietary zinc deficiency is known to decrease food intake in animal models and zinc supplementation improves taste acuity in elderly subjects (Pepersack et al. 2001; Stewart-Knox et al. 2008; Amani et al. 2010). Inadequate zinc intake certainly contributes to deficiency in many elderly patients (Singh et al. 1998; Pepersack et al. 2001) but effects of chronic inflammation and age-related decline in zinc transport mechanisms may also contribute to a functional zinc deficiency (Turnlund et al. 1986; Wong et al. 2012). "
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    • "Moreover, in addition to changes associated with aging and aging-related diseases (Lang et al., 2006), several other factors may affect taste perception in the elderly leading to taste disorders that could be broadly classified as complete loss of taste, partial loss of taste, or taste distortion (Doty et al., 2003). These factors include oral health (Saunders et al., 2007), accumulative effects of drug administration (Ackerman and Kasbekar, 1997; Doty et al., 2008; Ikeda et al., 2008) and zinc deficiency (Stewart-Knox et al., 2008). Additionally , some individuals are genetically predisposed to certain tastes. "
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