INDIA: As Vitamin D plays a key role in insulin sensitivity and glucose metabolism, Vitamin D deficiency may contribute to the development and progression of type 2 diabetes mellitus (T2DM), a recent study has concluded.
The study is scheduled to appear in the July-September issue of the journal. Apollo MedicineResearchers have found an inverse correlation between vitamin D and glycated hemoglobin (HbA1c) levels in people with type 2 diabetes, but suggest that this correlation could be restored with vitamin D therapy to help control blood sugar levels.
“Our study revealed a remarkable inverse correlation between vitamin D levels and HbA1c in patients with type 2 diabetes. Simply put, the higher the vitamin D levels, the better the glycemic control,” Rinki Kumari of the Centre for Advanced Traditional and Genomic Medicine at the Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India, told Medical Dialogue.
“This finding adds valuable insight to diabetes research and suggests that maintaining adequate vitamin D levels may help people manage their blood sugar levels more effectively.”
Commenting on the implications of the study findings, Dr Rinke said: “These results have important implications for both clinical practice and public health. Clinically, they suggest that monitoring and managing vitamin D levels may become part of the standard of care for patients with type 2 diabetes. By ensuring adequate vitamin D levels, healthcare professionals may be able to improve diabetes management and patient outcomes. From a public health perspective, promoting vitamin D supplements and encouraging safe sun exposure may help prevent diabetic complications and support overall health.”
Although it is crucial to obtain vitamin D from dietary sources such as sun exposure, oily fish and fortified foods, vitamin D deficiency is widespread, especially in areas with limited sunlight and dietary diversity. In diabetic patients, vitamin D has a complex role in glucose metabolism, affecting insulin sensitivity and secretion mechanisms in the pancreas. Deficiency of this vitamin has been linked to serious health conditions such as cardiovascular disease, diabetes, cancer and multiple sclerosis (MS).
Dr. Kumari and colleagues aimed to investigate the correlation between vitamin D levels and HbA1c in patients with type 2 diabetes and healthy controls.
The study involved 163 patients with type 2 diabetes (group I) and 174 healthy subjects (group II).The researchers measured serum vitamin D and HbA1c levels using radioimmunoassay and high-performance liquid chromatography.
The study yielded the following results:
• Group I, consisting of type 2 diabetes patients, had significantly lower vitamin D levels (17.82 ± 2.23 ng/mL) than group II. Correspondingly, type 2 diabetes patients also had higher HbA1c levels, indicating poorer glycemic control, which was statistically significant.
• Further analysis within group I showed a negative correlation between vitamin D and HbA1c levels.
• Combining data from both groups strengthened the inverse relationship, indicating that lower vitamin D levels were associated with higher HbA1c levels across the entire study population.
“What makes this study unique is that it looked at both diabetic and non-diabetic patients, providing a broader perspective on how vitamin D levels impact overall metabolic health. By comparing the two groups, the study provides new insights into the potential role of vitamin D in managing diabetes and promoting overall health. This comprehensive approach may integrate vitamin D assessment and management into routine healthcare practice, paving the way for new strategies in diabetes care,” explained Dr Kumari.
In conclusion, this study found a high prevalence of vitamin D deficiency in group I. Furthermore, a significant finding was the negative correlation between vitamin D and HbA1c levels. It is well known that vitamin D plays a pivotal role in glucose metabolism and insulin sensitivity, suggesting that vitamin D deficiency may contribute to the development and progression of T2DM.
Previous intervention studies demonstrating enhanced glycemic regulation with vitamin D supplementation are consistent with existing research, however, determining the optimal dose and duration of vitamin D supplementation remains a topic of ongoing debate among researchers. Although recommending 2000 IU of cholecalciferol daily for 16 weeks is a reasonable starting point for clinicians, it is important to assess each individual’s vitamin D status, medical history, and potential drug interactions before making a recommendation. An individualized approach to vitamin D supplementation is essential to ensure safety and effectiveness.
The findings of this study highlight the importance of assessing vitamin D status in patients with type 2 diabetes and the potential benefit of vitamin D supplementation in improving glycemic control.
According to Dr. Kumari, a limitation of this study is that it is observational, so it cannot conclusively prove that vitamin D deficiency is the cause of poor blood sugar control. Additionally, the sample size was relatively small, which may limit the applicability of the results to the wider population.
“Future research should focus on conducting long-term intervention studies to determine whether vitamin D supplementation can improve HbA1c levels. Expanding studies to include a more diverse group of participants would also help to confirm and extend these findings,” she concluded.
Quote:
Shukla J, Singh A, Sachan N, Verma RS, Kumari R, Dubey GP, et al. Evaluation of correlation between vitamin D levels and glycosylated hemoglobin in type 2 diabetes and non-diabetics. Apollo Med 2024;XX:XX-XX.
