Dietary zinc intake and whole blood zinc concentration in subjects with type 2 diabetes versus healthy subjects: A systematic review, meta-analysis and meta-regression

Abstract

The aim of this systematic review, meta-analysis and meta-regression was to examine the relationship between type 2 diabetes mellitus (T2DM) and concentration of zinc in whole blood, as well as dietary zinc intake. Searches were performed using Ovid MEDLINE, Embase (Ovid) and The Cochrane Library (CENTRAL). Observational studies conducted on diabetic and healthy adults, with data on dietary zinc intake and/or concentration of zinc in whole blood, were selected. The search strategy yielded 11,150 publications and the manual search 6, of which 11 were included in the meta-analyses. Mean difference (MD) and 95% confidence interval (CI), were calculated using the generic inverse-variance method with random-effects models. Heterogeneity was assessed by the Cochran Q-statistic and quantified by the I statistic. Meta-regressions and stratified analysis were used to examine whether any covariate had influence on the results. The pooled MD for the dietary zinc intake meta-analysis was -0.40 (95% CI: -1.59 to 0.79; I = 61.0%). Differences between diabetic and non-diabetic subjects became significant in the presence of complications associated with diabetes (MD = -2.26; 95% CI: -3.49 to -1.02; I = 11.9%). Meta-regression showed that for each year since the diagnosis of diabetes the concentration of zinc in whole blood decreased in diabetic patients regarding healthy controls [MD (concentration of zinc in blood) = 732.61 + (-77.88303) × (duration of diabetes in years)], which is not generally explained by a lower intake of zinc.

Zinc Intake and Status and Risk of Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis

“…Meanwhile, Simic et al [19], did not find a significant relationship in previously diagnosed T2DM patients and control subjects. These results seem to suggest that when T2DM is in the early stages, i.e., newly diagnosed, zinc levels are more elevated than non-diabetic subjects, and progressively they are reduced as the disease progresses, which is consistent with our previous systematic review and meta-analysis [20]. That meta-analysis which aimed to compare whole blood zinc concentration between T2DM patients and non-diabetic subjects, showed that duration of T2DM had a relevant influence on concentration of zinc in whole blood [20].…”

“…These results seem to suggest that when T2DM is in the early stages, i.e., newly diagnosed, zinc levels are more elevated than non-diabetic subjects, and progressively they are reduced as the disease progresses, which is consistent with our previous systematic review and meta-analysis [20]. That meta-analysis which aimed to compare whole blood zinc concentration between T2DM patients and non-diabetic subjects, showed that duration of T2DM had a relevant influence on concentration of zinc in whole blood [20]. In addition, we found a lower whole blood zinc concentration in T2DM patients; however, this group had, at least, 10.2 ± 8.6 years of duration of diabetes, and differences between cases and controls in that study were not observed [58], in concordance with the study of Simic et al [19], among previously diagnosed T2DM participants [19].…”

“…The study conducted on newly diagnosed T2DM patients found a positive association between whole blood zinc concentration and T2DM [18], while the study performed in previously diagnosed T2DM patients showed no association [19]. In our previous systematic review and meta-analysis, which aimed to compare whole blood zinc concentration between T2DM patients and non-diabetic subjects, we observed a lower whole blood zinc concentration in T2DM patients [20]. It should be noted that diabetic subjects had, at least, 10.2 ± 8.6 years of duration of diabetes.…”

Nutritional status and social determinants in a random sample of subjects residing in South-Eastern Serbia: Towards personalized nutrition practice

“…Our data are comparable to YU-SAD data for adult category, however our data indicate slightly lower intake of zinc within both adolescent groups. A comprehensive systematic review, meta-analyses and meta-regression, demonstrated significantly lower intake of zinc among diabetic patients, only if the condition is with associated co-morbidities (Fernández-Cao et al, 2018). However, blood zinc status was lower in diabetic subjects in comparison with healthy controls, regardless of the complications, indicating necessity for adequate biomarkers of the nutrient intake (Fernández-Cao et al, 2018).…”

Pengaruh Konsumsi Buah jeruk (Citrus reticulata) dan Suplementasi Zinc terhadap Kadar Glukosa Darah Puasa pada Wanita Diabetes Melitus Tipe 2

“…Peranan transporter zinc yang lain pada fungsi sel β memungkinkan konstribusinya pada tatalaksana hiperglikemi pada pasien diabetes 6 . Konsentrasi zinc secara signifikan lebih rendah pada pasien diabetes dibanding dengan non diabetes 7 . Pasien DM Tipe2 memiliki kadar zinc yang lebih rendah dan hal ini terkait dengan tingginya komplikasi mikrovaskular diabetes 8 .…”