The Effect of Zinc Supplementation on Serum Adiponectin Concentration and Insulin Resistance in First Degree Relatives of Diabetic Patients

Objective: Adiponectin (an insulin sensitizing protein) and zinc have insulin like effect. This study was conducted to assess the effect of zinc supplementation on serum adiponectin and insulin resistance in first degree relatives of diabetic patients. Materials and Methods: This study was a randomized clinical trial performed on 58 first degree relatives of diabetic patients with normal glucose tolerance test and body mass index (BMI) more than 25Kg/m2. The subjects were divided into two groups: a case group which consumed 50mg zinc orally per day for twelve weeks and another group that was not given zinc but regular exercise and weight control were recommended. Adiponectin, fasting blood glucose, insulin and insulin resistance were calculated by the homeostasis model assessment (HOMA) and lipid profile was measured in both groups before and after treatment. Results: The mean age and BMI of participants were 37.6±7.4 years and 28.8±3.5 Kg/m2 respectively. The level of adiponectin increased significantly from 1.67 ±1.29 to 3.67± 3.08 mIU/ml in subjects who received 50 mg zinc compared to the control group (p=0.001). HOMA decreased from 1.89±1.07 to 1.54±1.34 in subjects who consumed zinc, but this reduction was not significant (p=0.13). Conclusion: Zinc significantly increases the level of adiponectin in first degree relatives of diabetic patients. The level of insulin and HOMA index after zinc supplementation decreased but this reduction was not significant.