Zinc, as an essential trace element in human body, plays an important role in glycemic control. A growing body of evidence supports an association between hyperglycemia and zinc metabolism in human. However, because health status, the dose, duration, and formulation of the zinc intervention, and the genetic background of the individuals vary among studies, the overall role of zinc on preventing and treating diabetes has remained inconclusive. In recent years, interest in the the preventive and therapeutic effects of zinc supplementation on diabetes mellitus has increased considerably.
The researchers from Prof. WANG Fudi’s group conducted a meta-analysis of the data extracted from randomized controlled trials. “Zinc supplementation could improve the control of blood glucose (fasting and postprandial), insulin sensitivity (fasting insulin and HOMA-IR), glycosylation damage (HbA1c), and chronic inflammation (hs-CRP) in subjects with diabetes and subjects at high risk for developing diabetes.” said by WANG Xinhui, the first author of this study.
The subjects in the zinc supplementation group had a statistically significant reduction in fasting glucose (FG, WMD: -14.15 mg/dL; 95% CI: -17.36, -10.93 mg/dL).
The subjects in the zinc supplementation group had a statistically significant reduction in 2-hour postprandial glucose (2h-PG, WMD: -36.85 mg/dL; 95% CI: -62.05, -11.65 mg/dL).
The subjects in the zinc supplementation group had a statistically significant reduction in fasting insulin (FI, WMD: -1.82 mU/L; 95% CI: -3.10, -0.54 mU/L).
The subjects in the zinc supplementation group had a statistically significant reduction in homeostasis model assessment for insulin resistance (HOMA-IR, WMD: -0.73; 95% CI: -1.22, -0.24).
The subjects in the zinc supplementation group had a statistically significant reduction in glycosylated hemoglobin (HbA1c, WMD: -0.55%; 95% CI: -0.84, -0.27%).
The subjects in the zinc supplementation group had a statistically significant reduction in high-sensitivity C-reactive protein (hs-CRP, WMD: -1.31 mg/L; 95% CI: -2.05, -0.56 mg/L).
Moreover, subgroup analyses revealed that the effects of zinc supplementation on FG are significantly influenced by diabetic status and the formulation of the zinc supplement. The results support the notion that zinc supplementation may have clinical potential as an adjunct therapy for preventing and managing diabetes.
