Article

Reference Values for Serum Zinc Concentration and Prevalence of Zinc Deficiency in Adult Iranian Subjects

Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, No. 24, Parvaneh Street, Velenjak, Tehran, Iran, P.O. Box 19395-4763.
Biological trace element research (Impact Factor: 1.75). 05/2012; 149(3). DOI: 10.1007/s12011-012-9445-2
Source: PubMed

ABSTRACT

Zinc, as an essential trace element for health, plays various biological roles in human body functions. Serum zinc reference values are essential for assessing zinc-associated abnormalities and the prevalence of zinc deficiency. This study aims at determining age- and sex-specific reference values for serum zinc concentrations in adult Iranian subjects. Serum zinc concentration was measured by flame atomic absorption spectrometry in 4,698 adult subjects, aged 20-94 years, randomly selected from the population of the Tehran, Lipid, and Glucose Study. After application of exclusion criteria, reference values for serum zinc were determined in 2,632 apparently healthy subjects according to guidelines of the International Federation of Clinical Chemistry (nonparametric method). Dietary zinc was assessed in 2,906 individuals, of which 1,685 were healthy subjects, using a validated semiquantitative food frequency questionnaire. Reference values for serum zinc concentrations ranged between 9.6 and 31.6, 8.9 and 29.9, and 9.3 and 30.8 μmol/L in men, women, and the total population, respectively. Prevalence of serum zinc deficiency was 3.0 and 2.4 % in men and women, respectively (p = 0.267); in men, but not in women, the prevalence increased significantly with age (p for trend <0.001). Of the total participants, 10.3 % (6.5 men and 3.8 % women, p < 0.01) had lower zinc intake compared to dietary reference intakes. The zinc density of the population was 6.3 mg/1,000 kcal. In conclusion, this study presents reference values for serum zinc concentration in adult Iranian subjects for both sexes and different age groups. Prevalence of serum zinc deficiency and dietary zinc inadequacy seems to be lower in Iranians, compared to some other populations.

Download full-text

Full-text

Available from: Firoozeh Hosseini-Esfahani, Feb 16, 2014
  • Source
    • "Finally, gloves, needles and syringes used in the current study were not zinc-free. We washed all other laboratory ware in nitric acid; in addition, we assessed accuracy of the assay as the key feature for validation purposes (Ghasemi & Zahediasl, 2012b), using a certified reference material, and determined the recovery of the assay; both parameters had acceptable values. However, 11% of cases were excluded as outliers, suggesting the possibility of contamination of some samples. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Abstract Background: Zinc, a co-factor of antioxidant enzymes, may be involved in the pathophysiology of metabolic syndrome (MetS). Aim: To determine the association between serum zinc concentration and MetS in a population-based study. Subjects and methods: In the Tehran Lipid and Glucose Study, serum zinc concentration was measured by flame atomic absorption spectrometry in 2626 adult participants. After removal of outliers, usable data was available for 2401 participants. Dietary zinc was assessed by a validated semi-quantitative food frequency questionnaire. Results: Compared to those without the MetS, serum zinc concentration was significantly higher in men with syndrome (17.1 ± 4.9 vs 16.5 ± 4.6 μmol/L, p = 0.035); however, values were comparable in females (16.1 ± 4.8 vs 15.8 ± 4.4, p = 0.460). Men in tertile 3 of serum zinc had significantly higher chances of having MetS, even after multivariate adjustment (OR = 1.48, 95% confidence interval (CI) = 1.07-2.06, p = 0.020). Women in tertile 2 of serum zinc had significantly lower chances of having MetS, which remained significant after multivariate adjustment (OR = 0.68, 95% CI = 0.47-0.99, p = 0.046). Conclusion: This study observed a gender difference between serum zinc and MetS, with higher levels being positively associated with MetS in men and having a protective effect in women. Further studies are needed to elucidate the role of zinc status in the development of MetS.
    Full-text · Article · Mar 2014 · Annals of Human Biology
  • [Show abstract] [Hide abstract]
    ABSTRACT: Major depression occurs in 4.4% to 20% of the general population. Studies suggest that major depression is accompanied by immune dysregulation and activation of the inflammatory response system (IRS). Our objective was to quantitatively summarize the data on concentrations of specific cytokines in patients diagnosed with a major depressive episode and controls. We performed a meta-analysis of studies measuring cytokine concentration in patients with major depression, with a database search of the English literature (to August 2009) and a manual search of references. Twenty-four studies involving unstimulated measurements of cytokines in patients meeting DSM criteria for major depression were included in the meta-analysis; 13 for tumor necrosis factor (TNF)-alpha, 9 for interleukin (IL)-1beta, 16 for IL-6, 5 for IL-4, 5 for IL-2, 4 for IL-8, 6 for IL-10, and 4 for interferon (IFN)-gamma. There were significantly higher concentrations of TNF-alpha (p < .00001), weighted mean difference (WMD) (95% confidence interval) 3.97 pg/mL (2.24 to 5.71), in depressed subjects compared with control subjects (438 depressed/350 nondepressed). Also, IL-6 concentrations were significantly higher (p < .00001) in depressed subjects compared with control subjects (492 depressed/400 nondepressed) with an overall WMD of 1.78 pg/mL (1.23 to 2.33). There were no significant differences among depressed and nondepressed subjects for the other cytokines studied. This meta-analysis reports significantly higher concentrations of the proinflammatory cytokines TNF-alpha and IL-6 in depressed subjects compared with control subjects. While both positive and negative results have been reported in individual studies, this meta-analytic result strengthens evidence that depression is accompanied by activation of the IRS.
    No preview · Article · Dec 2009 · Biological psychiatry
  • [Show abstract] [Hide abstract]
    ABSTRACT: To determine pediatric reference values for serum zinc concentration in Iranian subjects. Serum zinc concentration was measured by flame atomic absorption spectrometry in 699 children and adolescents. Reference values for serum zinc were determined according to the Clinical and Laboratory Standards Institute/International Federation of Clinical Chemistry guidelines. Dietary zinc intake was assessed using a validated semiquantitative food frequency questionnaire. Overall 95% reference values for serum zinc concentrations were 9.7-31.5, 9.2-30.9, and 9.3-31.1μmol/L in boys, girls, and total population respectively. Serum zinc concentrations were comparable in boys and girls (17.5±5.3μmol/L vs. 17.2±5.6μmol/L, p=0.242). The dietary zinc intake of 7.6% (4.9% boys and 10.2% girls, p<0.01) was lower than the estimated average requirement. This study presents pediatric reference values for serum zinc concentrations, values that could help diagnose and manage zinc deficiency in pediatrics.
    No preview · Article · Jul 2012 · Clinical biochemistry
Show more