Introduction: In addition to the known risk factors, the role of different micronutrients such as selenium in the incidence of diabetes has been proposed. Several studies demonstrated a relationship between selenium deficiency and type II diabetes, while others did not confirm this relationship. This study aimed to evaluate the serum selenium level in patients with type II diabetes compared to a control group.

Materials and Method: This cross-sectional cohort study was conducted on the patients with type II diabetes in Zahedan, Iran. This study was conducted on 280 individuals divided into two groups. The case group consisted of 140 patients newly diagnosed with type II diabetes, and the control group included 140 individuals from the general population with normal blood sugar level. The control group subjects were matched in pairs with those of the case group based on gender, age (±1 year), and body mass index (±1). The serum selenium level was determined by spectrometry, and the obtained results were compared using t-test.

Results: The mean serum selenium level in the patients was 91.68±16.78 μg/L, while it was 144.25±21.96 μg/L in the control group. There was a significant difference between the groups regarding the mean serum selenium level (P<0.001). The serum selenium level of the diabetic patients was significantly lower in comparison to the control group.

Conclusion: According to the results, low serum selenium level was associated with the incidence of diabetes. A larger sample size is required to evaluate the serum selenium level in diabetic patients. Moreover, further prospective studies are recommended to investigate the effect of selenium supplementation on the incidence of diabetes.