The impact of vitamin D3 supplementation on glycemic control in type-2 diabetes mellitus at a tertiary care hospital

Neeta Banzal, Anupama Desai


Background: It has been estimated that at least one billion people worldwide have vitamin D3 deficiency. Type 2 diabetes mellitus has consistently been shown to be prevalent in individuals with vitamin D3 deficiency. This study focuses on exploring if there is any association between vitamin D3 deficiency, type 2 diabetes mellitus and glycemic control, by measuring HbA1c levels, after vitamin D3 supplementation.

Methods: 77 patients with confirmed type II diabetes mellitus were enrolled during the study. Pre and post treatment (after 3 month) laboratory investigations - FBS, PPBS, HbA1c and serum vitamin D3 levels were done in all the patients. Patients were classified into two groups. Group 1 - vitamin D3 < 30 ng/ml (n=41) and group 2 - vitamin D3 ≥30 ng/ml (n=36). Group 1 was given 60,000 IU of calcitriol sachet weekly for 8 weeks followed by 60,000 IU once a month. No vitamin D3 supplementation was given to group 2.

Results: Vitamin D3 supplementation in group 1, has resulted in number of patients with control on HbA1c (< 7%) increased from 8 to 17 (a more than 100% increase). Number of patients with control on FBS (<130 mg/dl) increased from 14 to 23 (64% increase). 

Conclusions: There is a positive association between vitamin D3 status and glycemic control in type 2 diabetic mellitus patients. Vitamin D3 supplementation in deficient group has resulted in significant reduction in HbA1c level (p<0.001).


Vitamin D deficiency, Type 2 diabetes, Glycemic control, HbA1c, FBS, PPBS

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