Vitamin D Deficiency Linked to Poor Glycemic Control in Type 2 Diabetes, reports research

A new study published in the journal of BMC Endocrine Disorders revealed that Vitamin D deficiency is common in people with type 2 diabetes mellitus (T2DM) and is associated with male gender, older age, poor blood sugar control, and diabetic nephropathy.

This research emphasized that diabetes mellitus remains a leading cause of disease and death globally, with poor glycemic control driving complications such as kidney disease, cardiovascular disorders, and nerve damage. The findings of this study suggest that screening for vitamin D deficiency could become an important component of routine diabetes care, especially among older male patients and those with poorly controlled blood sugar.

This research conducted a cross-sectional study which involved 100 patients diagnosed with T2DM and 100 healthy individuals matched by age and sex. The study investigated how common vitamin D deficiency is among diabetic patients and whether it is associated with worsening blood sugar control and declining kidney function.

The findings revealed that vitamin D deficiency is notably more prevalent among individuals with T2DM than in non-diabetic controls. About 14% of diabetic participants had vitamin D deficiency, which was defined as serum 25-hydroxyvitamin D levels of 20 ng/mL or lower, while 31% showed vitamin D insufficiency. In contrast, only 5% of the control group were deficient and 20% insufficient.

Nearly all diabetic patients with vitamin D deficiency ( around 93%) had evidence of nephropathy, which can progress to chronic kidney disease and eventually end-stage renal disease. Kidney impairment was significantly more common among diabetic participants overall, with 12% showing stage 3 chronic kidney disease or worse, when compared to just 4% of the control group.

Also, older age was associated with a higher risk of deficiency, while men were found to be at particularly elevated risk. Poor glycemic control, measured using glycated hemoglobin (HbA1c), also strongly correlated with lower vitamin D levels.

Every increase in HbA1c significantly raised the odds of vitamin D deficiency, which suggests that inadequate vitamin D may contribute to difficulty controlling blood glucose levels. The association supports growing evidence that vitamin D plays a role in insulin sensitivity and metabolic regulation.

Despite the study not establishing a direct cause-and-effect relationship, the findings strengthen the argument for further research into whether vitamin D supplementation could help improve diabetes outcomes and slow kidney damage progression.

Reference:

Lawal-Bello, A. T., Soyoye, D. O., Ikem, R. T., Fasanu, A. N., & Kolawole, B. A. (2026). Relationship between vitamin D status, glycaemia and nephropathy in adults with type 2 diabetes mellitus. BMC Endocrine Disorders. https://doi.org/10.1186/s12902-026-02317-8