Supplemented zinc does not alter mood in healthy older European adults - a randomised placebo-controlled trial: the Zenith study

Abstract

OBJECTIVE: Older people are vulnerable to zinc deficiency, which may impact upon their mood. This randomised, placebo-controlled, double-blind intervention study aimed to investigate the effect of oral zinc gluconate supplementation (15 mg/d; 30 mg/d; and placebo) on subjective mood (affect) in older Europeans. SUBJECTS: Healthy volunteers (n 387) aged 55-87 years were recruited. SETTING: Volunteers in Rome (Italy; n 108) and Grenoble (France; n 91) were aged 70-87 years and those in Coleraine (Northern Ireland; n 93) and Clermont-Ferrand (France; n 95) were aged 55-70 years. DESIGN: Mood was measured using the Positive and Negative Affect Scale on four occasions per day over 4 d at baseline, 3 and 6 months post-intervention. RESULTS: Mixed ANOVA indicated that neither positive nor negative affect altered in response to zinc (15 mg/d or 30 mg/d) compared to placebo in either the 55-70 years or the >/=70 years age group. CONCLUSIONS: These results suggest that zinc does not benefit mood in healthy older people.