Zinc supplementation and the effects on metabolic status in gestational diabetes: A randomized, double-blind, placebo-controlled trial
Authors: Ahmad Esmaillzadeh
Mansooreh Samimi
Zatollah Asemi
Zahra Heidarzadeh
Seyed Morteza Seifati
Zohreh Tabassi
Maryam Karamali
Mohammad Hajijafari
Journal: Journal of Diabetes and its Complications (2015)
Discipline: CLINICAL MEDICINE
Keywords: Gestational diabetes; Insulin metabolism; Lipid concentrations; Supplementation; Zinc.
Affiliations: Department of Gynecology and Obstetrics, School of Medicine, Arak University of Medical Sciences, Arak, I.R. Iran; Department of Gynecology and Obstetrics, School of Medicine, Iran University of Medical Sciences, Iran, I.R. Iran., Department of Biology, Islamic Azad University, Ashkezar branch, Ashkezar, Iran., Department of Gynecology and Obstetrics, School of Medicine, Kashan University of Medical Sciences, Kashan, I.R. Iran., Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, I.R. Iran., Research Center for Biochemistry and Nutrition in Metabolic Diseases, Kashan University of Medical Sciences, Kashan, I.R. Iran. Electronic address: ., Food Security Research Center, Isfahan University of Medical Sciences, Isfahan, Iran; Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran.

Abstract:  Objective: To the best of our knowledge, no reports are available indicating the effects of zinc supplementation on metabolic status in women with gestational diabetes (GDM). This study was designed to determine the effects of zinc supplementation on glucose homeostasis parameters and lipid concentrations in GDM women. Methods: This randomized, double-blind, placebo-controlled trial was performed among 58 women diagnosed with GDM, primigravida and aged 18-40years old. Patients were randomly divided into two groups to receive 233mg zinc gluconate (containing 30mg zinc) supplements (n=29) or placebo (n=29) per day for 6weeks. Fasting blood samples were taken at the beginning and end of the trial to quantify glucose, insulin and lipid concentrations. Results: Patients who received zinc supplements had significantly higher serum zinc concentrations (+6.9±13.2 vs. -1.5±16.5mg/dL, P=0.03) than those received the placebo. In addition, zinc-supplemented patients had reduced fasting plasma glucose (FPG) (-6.6±11.2 vs. +0.6±6.7mg/dL, P=0.005), serum insulin levels (-1.3±6.6 vs. +6.6±12.2μIU/mL, P=0.003), homeostasis model of assessment-insulin resistance (HOMA-IR) (-0.5±1.6 vs. +1.5±2.7, P=0.001), homeostatic model assessment-Beta cell function (HOMA-B) (-0.7±25.0 vs. +26.5±49.5, P=0.01) and increased quantitative insulin sensitivity check index (QUICKI) (+0.01±0.01 vs. -0.01±0.02, P=0.004) compared with the placebo. Additionally, significant differences in serum triglycerides (+13.6±61.4 vs. +45.9±36.5mg/dL, P=0.01) and VLDL-cholesterol concentrations (+2.7±12.3 vs. +9.2±7.3mg/dL, P=0.01) were observed following the administration of zinc supplements compared with the placebo.We did not observe any significant effects of taking zinc supplements on other lipid profiles. Conclusions: Taken together, 30mg zinc supplementation per day for 6weeks among GDM women had beneficial effects on metabolic profiles. 

Retracted: No

PubPeer comments:
 There are many concerns about the integrity of 172 publications by this research group, including this one. Some of the concerns are published 1. Anaesthesia 2020;75:1683u201392, see Supplementary data. This paper is A38 2. Account Res 2020;28:149-61. 3. J Clin Epidemiol 2021;131:22-29. Journals and publishers were notified of these concerns in July 2019. 23 publications have an expression of concern. To our knowledge there has been no public response about any of the concerns. We think these publications are unreliable ,