The Impact of Zinc Supplementation in Diabetes: What Does the Research Say?

Zinc and diabetes

1. Zinc Supplementation for Glycemic Control in Diabetes

   • Study Type: Systematic Review and Meta-analysis

   • Authors and Year: Wang et al., 2019

   • Journal: The American Journal of Clinical Nutrition

   • Number of Patients: 1,700 participants across 32 trials

   • Findings: Zinc supplementation significantly reduced fasting glucose (WMD: -14.15 mg/dL), postprandial glucose (WMD: -36.85 mg/dL), insulin (WMD: -1.82 mU/L), HbA1c (WMD: -0.55%), and CRP levels (WMD: -1.31 mg/L). The benefits were more pronounced in subjects with diabetes receiving inorganic zinc.

   • Citation: Wang X, Wu W, Zheng W, et al. Zinc supplementation improves glycemic control for diabetes prevention and management: a systematic review and meta-analysis of randomized controlled trials. Am J Clin Nutr. 2019. DOI:10.1093/ajcn/nqz041

     
     

2. Zinc and Pre-diabetes Prevention

   • Study Type: Randomized Controlled Trial (RCT) Protocol

   • Authors and Year: Ranasinghe et al., 2013

   • Journal: Trials

   • Number of Patients: 200 adults

   • Findings: This double-blind RCT explores the impact of 20 mg/day zinc supplementation on fasting glucose, HbA1c, and lipid profiles in pre-diabetic adults. The study aims to evaluate zinc's potential to prevent diabetes over 12 months.

   • Citation: Ranasinghe P, Jayawardena R, Pigera A, et al. Zinc supplementation in pre-diabetes: study protocol for a randomized controlled trial. Trials. 2013;14:52. DOI:10.1186/1745-6215-14-52

     
     

3. Zinc in Type 2 Diabetes Management

   • Study Type: Meta-analysis of RCTs

   • Authors and Year: Ghaedi et al., 2023

   • Journal: Critical Reviews in Food Science and Nutrition

   • Number of Patients: 1,442 participants across 22 RCTs

   • Findings: Zinc supplementation reduced fasting blood glucose (MD: -23.32 mg/dL), HbA1c (MD: -0.47%), and triglycerides (MD: -18.23 mg/dL). It also improved lipid profiles by lowering LDL cholesterol and raising HDL cholesterol levels.

   • Citation: Ghaedi K, Ghasempour D, Jowshan M, et al. Effect of zinc supplementation in the management of type 2 diabetes: A meta-analysis of randomized controlled trials. Crit Rev Food Sci Nutr. 2023. DOI:10.1080/10408398.2023.2209802

     
     

4. Zinc’s Role in Diabetes Prevention in Insulin-Resistant Adults

   • Study Type: Systematic Review (Cochrane)

   • Authors and Year: Beletate et al., 2007

   • Journal: Cochrane Database of Systematic Reviews

   • Number of Patients: 56 obese women

   • Findings: This review found no significant improvement in insulin resistance or lipid parameters with zinc supplementation. The study concludes that more robust trials are needed to determine zinc’s role in preventing type 2 diabetes.

   • Citation: Beletate V, El Dib R, Atallah Á. Zinc supplementation for the prevention of type 2 diabetes mellitus. Cochrane Database Syst Rev. 2007;1

     . DOI:10.1002/14651858.CD005525.PUB2