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Objective:To report the rational, design, recruitment, baseline characteristics and preliminary overview of volunteers in the ZENITH study.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:Healthy men and women middle-aged (55–70 y) and older volunteers (70–87 y).Interventions:At baseline (prior to zinc (Zn) supplementation), all volunteers underwent a full clinical examination, anthropometric measurements, health and lifestyle questionnaire, Mini Mental State Examination, Geriatric Depression Scale, and biochemistry profile.Results:In total, 842 volunteers (378 men and 464 women) were invited to take part in the study. A total of 49% of these volunteers were excluded on the basis of inclusion/exclusion criteria. In total, 433 participants were admitted to the Zn supplementation for 6 months. During this period, about 10% of volunteers dropped out from the study.Conclusions:A total of 387 subjects (197 male and 190 female subjects) successfully completed the supplementation phase of the ZENITH study.Sponsorship:The ZENITH study is supported by the European Commission ‘Quality of Life and Management of Living Resources’ Fifth Framework Programme, Contract No: QLK1-CT-2001-00168.European Journal of Clinical Nutrition (2005) 59, Suppl 2, S8–S12. doi:10.1038/sj.ejcn.1602287 [ABSTRACT FROM AUTHOR]

Objective:This paper describes baseline data on basal metabolic rate (BMR), thyroid hormone levels and body composition of middle-aged and older people participating in the ZENITH project and the correlation of thyroid hormone levels with zinc status.Design:A multicentre prospective intervention study employing a randomised double blind design.Setting:Clermont-Ferrand, Theix (France), Coleraine (Northern Ireland), Grenoble (France), Rome (Italy).Interventions:BMR has been measured on a subsample of 70 middle-aged volunteers (35 men and 35 women recruited in Clermont-Ferrand, France, aged 55–70 y) and 108 older volunteers (56 men and 52 women recruited in Rome, Italy, aged 70–85 y). Thyroid hormone levels were evaluated in the entire group of ZENITH volunteers (n=387). BMR was measured by indirect calorimetry. Fat-free mass (FFM) was derived by four skinfold thicknesses using Durnin and Womersley's equations. Concentrations of thyroid hormones (total T3 and T4) were measured using a competitive immunoassay with an enhanced chemiluminescence end point.Results:Italian older volunteers had a significantly lower FFM than middle-aged French volunteers (−7% P<0.01). A negative correlation between BMR and age (men, r= −0.64; women, r= −0.62; both P<0.0001) was observed: BMR was significantly (P<0.000001) lower in Italian elderly volunteers (4.03±0.46 kJ/min and 3.29±0.42 kJ/min for men and women, respectively) than in middle-aged French volunteers (4.84±0.45 kJ/min and 3.87±0.38 kJ/min for men and women, respectively), even after adjustment for FFM (−12%). No correlation has been observed between BMR and thyroid hormones both in French and Italian subjects. Total T4 (TT4) concentrations were lowest in middle-aged population (−10%, P<0.0001). A moderate negative correlation has been found with TT4 and red blood cell zinc (r=−0.12, P<0.02, slope −0.026).Conclusions:The results confirm an age-related decline in BMR not entirely explained by body composition or thyroid hormones differences.Sponsorship:The ZENITH study is supported by the European Commission ‘Quality of Life and Management of Living Resources’, Fifth Framework Programme, Contract no. QLK1-CT-2001-00168.European Journal of Clinical Nutrition (2005) 59, Suppl 2, S53–S57. doi:10.1038/sj.ejcn.1602299 [ABSTRACT FROM AUTHOR]

Objective:To investigate the relationship between indices of zinc nutritive status and biochemical markers of bone turnover in older adult European subjects.Design:Use of baseline data from a multicentre prospective zinc intervention (ZENITH) study.Setting:Centres in France, Italy and Northern Ireland.Participants:A total of 387 healthy adults, aged 55–87 y.Methods:Zinc intake was assessed by 4-day recall records. Circulating and urinary biochemical zinc status measures were assessed by atomic absorption spectrophometry. Serum bone-specific alkaline phosphatase and osteocalcin were assessed by ELISA and urinary pyridinoline (Pyr) and deoxypyridinoline (Dpyr) by HPLC.Results:Zinc intake was negatively correlated with urinary Pyr and Dpyr (r=−0.298 and −0.304, respectively; P<0.0001), but was not correlated with bone formation markers. There was a tendency for serum zinc to be negatively correlated with urinary Dpyr (r=−0.211; P=0.080). Erythrocyte zinc was negatively correlated with serum osteocalcin (r=−0.090; P<0.0001). None of the other correlations were significant. After adjustment for confounder (age, gender and research centre) the only significant association that remained was between serum osteocalcin and erythrocyte zinc (β=−0.124; P=0.011).Conclusions:There was some, albeit inconsistent, evidence of a relationship between zinc nutritive status and bone turnover in the older adult participants of the ZENITH study.Sponsorship:ZENITH is supported by the European Commission ‘Quality of Life and Management of Living Resources’ Fifth Framework Programme, Contract No: QLK1-CT-2001-00168.European Journal of Clinical Nutrition (2005) 59, Suppl 2, S73–S78. doi:10.1038/sj.ejcn.1602303 [ABSTRACT FROM AUTHOR]

The oxidative modification of low-density lipoprotein cholesterol (LDL) has been implicated in the pathogenesis of atherosclerosis. Copper (Cu) is essential for antioxidant enzymes in vivo and animal studies show that Cu deficiency is accompanied by increased atherogenesis and LDL susceptibility to oxidation. Nevertheless, Cu has been proposed as a pro-oxidant in vivo and is routinely used to induce lipid peroxidation in vitro. Given the dual role of Cu as an in vivo antioxidant and an in vitro pro-oxidant, a multicenter European study (FOODCUE) was instigated to provide data on the biological effects of increased dietary Cu. Four centers, Northern Ireland (coordinator), England, Denmark, and France, using different experimental protocols, examined the effect of Cu supplementation (3 or 6 mg/d) on top of normal Cu dietary intakes or Cu-controlled diets (0.7/1.6/6.0 mg/d), on Cu-mediated and peroxynitrite-initiated LDL oxidation in apparently healthy volunteers. Each center coordinated its own supplementation regimen and all samples were subsequently transported to Northern Ireland where lipid peroxidation analysis was completed. The results from all centers showed that dietary Cu supplementation had no effect on Cu- or peroxynitrite-induced LDL susceptibility to oxidation. These data show that high intakes (up to 6 mg Cu) for extended periods do not promote LDL susceptibility to in vitro-induced oxidation.