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 found a negative correlation between vitamin D levels and glycosylated hemoglobin (HbA1c) levels in type 2 diabetes. However, the researchers suggest that this correlation could be reversed with vitamin D therapy, which helps control blood sugar levels. The study will be published in the July-September issue of the Journal of Clinical Oncology. Apollo Medicine It is also available online ahead of its print release.
“Our study shows 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,” Dr Rinki Kumari of the Centre for Advanced Traditional and Genomic Medicine, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India, told Medical Dialogue.
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.
Our findings revealed a high prevalence of vitamin D deficiency in group I. Furthermore, a significant finding was the negative correlation between vitamin D and HbA1c levels. Vitamin D is well known to play a pivotal role in glucose metabolism and insulin sensitivity, suggesting that vitamin D deficiency may contribute to the development and progression of type 2 diabetes.
“From a public health perspective, promoting vitamin D supplementation and encouraging safe sun exposure may help prevent diabetes complications and support overall health,” added Dr Rinke.
“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,” Dr Kumari pointed out.
“Recommending 2,000 IU of cholecalciferol daily for 16 weeks is a reasonable starting point for clinicians, but 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 study states.
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. “Assessment of correlation between vitamin D levels and glycosylated hemoglobin in type 2 diabetic and non-diabetic patients.” Apollo Med 2024; https://doi.org/10.1177/09760016241238855
