To study the efficacy and safety of Vitamin D as an add-on therapy in patients of Type 2 diabetes mellitus on oral antidiabetic drugs

Ravneet K. Sandhu, Geeta Sharma, Satya B. Nayyar, Meenakshi Gupta


Background: Predominance of Type 2 diabetes mellitus (DM) is increasing globally at an alarming rate. Therapies for Type 2 DM have improved but still there is a need for new insights to limit the progression of the disease. Vitamin D deficiency has been associated with many non-skeletal disorders including Type 2 DM, suggesting a role in pathogenesis of Type 2 DM. Therefore, the present study was designed to investigate the effect of Vitamin D as an add-on therapy in patients of Type 2 DM whose glycemic status was uncontrolled with oral antidiabetic drugs.

Methods: This was a before and after, open labeled study of 12 weeks duration, conducted on 50 patients of Type 2 DM and Vitamin D deficiency. These patients were given 60,000 IU of Vitamin D3 orally/week for 12 weeks in addition to oral antidiabetic drugs. Effect of Vitamin D was observed on HbAIC, fasting blood glucose (FBG), 25(OH)D and calcium levels.

Results: At the end of 12 weeks, a highly significant reduction (p<0.001) was seen in FBG levels and HbAIC decreased significantly (p<0.05). Highly significant (p<0.001) increase was observed in 25(OH)D levels and calcium levels increased significantly (p<0.05). No untoward side effect was observed in any of the patients.

Conclusion: It establishes that Vitamin D therapy improves glycemic status thereby, delays the progression and consequently the complications of Type 2 DM. Therefore, supplementation of Vitamin D is a promising and safe adjuvant therapy in Vitamin D deficient Type 2 DM patients.


Diabetes mellitus, Vitamin D deficiency, Vitamin D

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