Effects of Selenium and Vitamin C Supplementation on the Glycemic Markers of Patients with Type II Diabetes: A Randomized Clinical Trial

Document Type : Research Paper


1 Department of Clinical Nutrition, School of Nutrition and Food Sciences, Shiraz University of Medical Science, Shiraz, I.R. Iran.

2 Department of Nutrition, Sarvestan Branch, Islamic Azad University, I.R. Iran.

3 Department of Nutrition, Persian Gulf Tropical Medicine Research Center, Bushehr University of Medical Sciences, Bushehr, I.R. Iran.


IntroductionGiven the global prevalence of diabetes, scientists recommend supplementation with minerals and vitamins to control hyperglycemia in diabetic patients.The present study aimed to investigate the effects of separate and combined selenium and vitamin C supplementation on the glycemic markers of patients with type II diabetes. Methods: In total, 65 patients with type II diabetes were selected from the patients referring to the Hospital and clinics in Bushehr port, Iran. After matching the samples, the patients were randomly assigned to four groups. The patients in groups one, two, and three respectively received vitamin C (1,000 mg), selenium (100 μg), and combined selenium and vitamin C daily and at the same doses for three months. In addition, group four received placebo (500 mg). Fasting plasma glucose (FPG) and glycated hemoglobin (HbA1c) were measured before and after the intervention. Results: In group three, HbA1c and FPG increased significantly compared to the other groups and the control group. Moreover, HbA1c and FPG decreased in groups one and two after the intervention compared to the baseline, which was not considered significant. Conclusion: According to the results, supplementation with vitamin C and selenium might induce insulin resistance in type II diabetic patients.


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