Relationship between Vitamin D and Autoimmune Thyroid Disease (AITD): A Review

Introduction: vitamin-D is important on various functions of the immune system. Concerning AITD, some studies showed that low vitamin-D status may increase the risk of AITD. However, the relationship between vitamin-D reduction and AITD, is still controversial. The aim was to evaluate the association between vitamin-D levels and AITD through literature review.Materials & Methods: This article provides a review of the literature on the Relationship between vitamin-D and AITD. PubMed, scopus and googlescholar databases identified about 1900 potentially relevant articles published between 2014 and 2019. A total of 10 articles, were selected.Results: the studies showed There is a link between vitamin-D deficiency and the presence of antithyroid antibodies and there may be a significant association between hypovitaminosis D and hypothyroidism. However, other studies failed to demonstrate a firm correlation, they suggesting that vitamin D deficiency does not increase the risk of AITD and is not associated with early-stage AITD and low vitamin -D levels are only a consequence of thyroid disease.Conclusion: some studies provide evidence pointing to a clear role of vitaminD in the pathogenesis of autoimmune diseases, especially AITD. however, others found only a weak correlation between vitamin-D and AITD. Clearly, further research is needed to confirm the involvement of vitaminD in AITD.