Objective: Oxidative stress has been reported to increase with ageing. However, the data in healthy humans remain controversial and studies in free-living elderly people are scarce. The objective of the present study was to compare age-related oxidative stress in late middle-aged and older free-living subjects. Design: The effect of ageing on oxidative stress and antioxidant parameters was investigated in 188 middle-aged subjects from Clermont-Ferrand (France) and Coleraine (UK), and in 199 older subjects from Grenoble (France) and Roma (Italy). Plasma thiol (SH) groups, define definition (TBAR's) and total glutathione (GSH), define definition (FRAP), and superoxide dismutase (SOD) activity were measured at baseline of the ZENITH study. Results: Plasma SH groups and FRAP and, surprisingly, TBAR's were significantly lower in free-living older subjects compared to younger subjects (Po0.001, Po0.001, Po0.01, respectively), but there was no significant differences in GSH levels. Conclusion: European free-living healthy older do not appear to be exposed to an acute oxidative stress. However, the highly significant positive correlation between plasma SH group oxidation or decreased FRAP and ageing is predictive of an increased risk of oxidative stress in older subjects. Moreover, the comparison between middle-aged and older subjects regarding oxidative stress parameters suggests also a progressive and slow decline of antioxidant status in healthy free-living older elderly and underline the impact on life-style factors on successful ageing.

Objective: Inadequate intakes of micronutrients in elderly negatively affect the nutritional status. Zinc is an essential micronutrient in the elderly, especially in relation to its impact on immune function, bone mass, cognitive function and oxidative stress. However, data are lacking on zinc intake and status during normal ageing. In this study, we evaluate the intake and status of zinc in late middle-aged and older free-living subjects. Design: Dietary zinc intake and zinc status in 188 middle-aged subjects from Clermont-Ferrand (Fr) and Coleraine (UK), and in 199 older subjects from Grenoble (Fr) and Roma (It) were assessed at the entry in the ZENITH study. Results: In relation to the zinc RDA for people older than 55 y, zinc intakes in most of the middle-aged and older subjects (more than 96%) in the present study were adequate. Older people had significantly lower (Po0.01) energy intakes as compared to middle-aged. Zinc intake expressed per MJ was also significantly (Po0.01) higher in older people compared to middle-aged. Erythrocyte and urinary zinc concentrations were significantly (Po0.001) higher in middle-aged subjects compared to older ones. The prevalence of biological Zn deficiency in free-living ageing European people was low (o5%). Conclusion:The results of the present study showed a relatively low prevalence of zinc deficiencies in healthy free-living late middle-age and older subjects. These results should be useful for health professionals to have reference data on zinc intake and status for a healthy ageing.

Background: Age-related decline in taste acuity may be both a cause and an effect of depleted zinc and/or increased zinc requirement. Objective: The aim of this study was to explore associations between zinc status and taste acuity in healthy older European adults aged 55-90 y. Sample: Volunteers were recruited within Italy (n ¼ 108 aged 70-90 y), the United Kingdom (UK) (n ¼ 93 aged 55-70) and two regions of France (n ¼ 186), Grenoble (aged 70-90 y) and Clermont-Ferrand (aged 55-70 y). Methods: A signal detection theory approach was adopted, employing a three-alternative, forced-choice procedure. The data were converted to R-indices and bivariate correlations were computed to explore relationships between serum zinc, erythrocyte zinc and taste acuity. ANOVA was undertaken to determine regional differences in zinc status. Results: Higher erythrocyte zinc status was associated with better acuity for salt (sodium chloride) taste in the sample as a whole (P ¼ 0.012) (n ¼ 385). Higher serum zinc levels were associated with greater sensitivity to sour taste (citric acid) (P ¼ 0.015) only in the older groups (aged 70-90 y). There were no apparent associations between serum or erythrocyte zinc status and acuity for bitter (quinine) or sweet (sucrose) tastes irrespective of age. Conclusion: These results agree with those previously suggesting that age-related detriment in sensitivity for salt taste may be associated with depleted zinc.

Objective: To report selected dietary intake and vitamin status at baseline of volunteers participating in the ZENITH study and the correlation of vitamin status with zinc. Design: A multicentre prospective intervention study employing a randomised double-blind design. Setting: Clermont-Ferrand, Theix (France), Coleraine (Northern Ireland), Grenoble (France), Rome (Italy). Participants: In total, 387 healthy middle-aged (55-70 y) and older (70-87 y) men and women participated in the study. Methods: Dietary intake was assessed by means of a validated 4-d recall record. Fasting blood samples were simultaneously analysed for retinol and a-tocopherol by the HLPC method. Erythrocyte folates were measured by a competitive immunoassay with direct chemiluminescence detection on an automatised immunoanalyser. Results: In all centres, men had a significantly (Po0.0001) higher mean nutrient intake than women. Comparison between age-groups showed that older individuals had significantly lower intakes of macro-and selected micronutrients than middleaged subjects (Po0.0001). A high fat intake (from 36 to 40% of total energy) was observed in all examined groups. In relation to biochemical measures of vitamin status, all parameters were above their respective cut-off values for normality and, thus, none of the subjects had biochemical evidence of deficiency of these selected vitamins. A moderate correlation was found with plasma vitamin A and serum zinc (r ¼ 0.12, Po0.05) or red blood cell zinc (r ¼ 0.12, Po0.01) and with erythrocyte folates and red blood cell zinc (r ¼ 0.11, Po0.05). Conclusions: There were only moderate differences in the nutrient intake of the ZENITH study volunteers among the four European centres. Their biochemical status for retinol, a-tocopherol and folate appeared adequate.

Background/Objectives: Few studies have been conducted on determinants of serum zinc concentration, especially in France. The aim of this study was to investigate the relationships between serum zinc concentrations, and age, education, living area and life style in a large sample cohort of French adults. Subjects/Methods: Blood samples were collected after 12-h fasting in French adults (7448 women, 35-65 years old and 4926 men, 45-65 years old) participating to the SUpplementation in AntioXidant VItamins and Minerals cohort at enrolment. Serum zinc was determined by flame atomic absorption. Results: Serum zinc concentration was lower in women (mean: 12.9 mmol/l, 95% confidence interval: 9.2-16.6 mmol/l) compared with men (mean: 13.4 mmol/l, 95% confidence interval: 9.7-17.1 mmol/l, Po0.0001). In total, 10% of the women showed serum zinc values o10.7 mmol/l and 10% of the men showed serum zinc values o11.3 mmol/l. Age was negatively associated with serum zinc only in men (P ¼ 0.001). In women, a positive association between smoking and serum zinc concentration (P ¼ 0.0003), and a negative relationship between highest education level and serum zinc concentration (P ¼ 0.01) were observed. With regard to geographical areas, the highest serum zinc concentrations were found in the Center, and the lowest in the Southwest of France for both men and women. The association between serum zinc concentrations and food categories or macronutrient intake disappeared after stratifying by gender. Conclusions: Age, gender and geographic area seem the main determinants of serum zinc concentrations in this study.