Vitamin D is an immunomodulatory hormone with an established role in calcium and phosphate metabolism and skeletal mineralization. Evidence showing its immunological benefits by regulating essential components of the innate and adaptive immune system is prevalent. Vitamin D deficiency is reported worldwide and is thereby found to be associated with various immune-related diseases. Rheumatoid Arthritis and COVID-19 are two such diseases, sharing a similar hyperinflammatory response. Various studies have found an association of lower Vitamin D levels to be associated with both these diseases. However, contrasting data is also reported. We review here the available scientific data on risk factor association and supplementation benefits of Vitamin D in Rheumatoid Arthritis and COVID-19, intending to critically evaluate the literature.

中文翻译：

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维生素 D 缺乏症：关注类风湿性关节炎和 COVID-19？

维生素 D 是一种免疫调节激素，在钙和磷酸盐代谢以及骨骼矿化中发挥着重要作用。有证据表明，其通过调节先天性和适应性免疫系统的重要组成部分而具有免疫学益处。维生素 D 缺乏症在世界范围内都有报道，因此发现与各种免疫相关疾病有关。类风湿性关节炎和 COVID-19 就是两种这样的疾病，它们具有相似的高炎症反应。多项研究发现，维生素 D 水平较低与这两种疾病有关。然而，也报告了对比数据。我们在此回顾了有关风湿性关节炎和 COVID-19 风险因素关联和补充维生素 D 益处的现有科学数据，旨在对文献进行严格评估。