The Schematic Assessment of Vitamin D Deficiency in Relation to Autoimmune Disorders and Its Implications in Internal Medicine.

The immune system greatly depends on vitamin D for modulating its function, despite the fact that deficiency of this nutrient is now well recognized as a factor that contributes to the development of several autoimmune disorders. This study observed the occurrence of vitamin D deficiency among autoimmune disease patients and investigated its implications in internal medicine. Two medical research investigators searched through several electronic databases such as PubMed, Scopus, Web of Science, and Google Scholar for studies ranging from 2018 to 2025. The research examined the findings of published studies that measured serum vitamin D levels of autoimmune disorder patients in conjunction with how this measurement affected disease activity, severity, and therapy results. A review process executed a predefined research eligibility framework and incorporated both observational and interventional study types for selection. The extraction of study data was done autonomously by two reviewers. Two tools were used to evaluate the methodological quality of the selected studies: the Newcastle-Ottawa Scale and the Cochrane Risk of Bias Tool. The strength of evidence was evaluated using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework. The research analysis included a total of eight studies that fulfilled the eligibility requirements. Most studies identified vitamin D deficiency as common among patients who suffered from rheumatoid arthritis, systemic lupus erythematosus, and multiple sclerosis. The literature showed increased severity of disease in patients with insufficient vitamin D levels. Some researchers also observed symptom improvement following vitamin D supplementation. Overall, the reviewed evidence suggested that vitamin D may be a potentially modifiable element in the management of autoimmune diseases. While research demonstrates a connection between vitamin D deficiency and autoimmune disease evolution, additional clinical testing must confirm the usefulness of vitamin D therapy in internal medicine.