The relationship between serum vitamin D level and COVID-19; a review study

Introduction: Coronavirus disease 2019 (COVID-19) from the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is one of the most important epidemiological events in the past 100 years has become, the consequences for public health and economic systems around the world. Vitamin D is an important micronutrient that has been reported to improve immunity and protect against respiratory diseases. In this study, we intend to review articles that examine the relationship between COVID-19 and vitamin D. Methods: This is a review that uses articles from studies published in 2020 on the relationship between COVID-19 and vitamin D in databases such as; Web of Science, Science Direct, SID, Magiran, Google Scholar and PubMed. Keywords used included; serum levels of 25-hydroxyvitamin D, vitamin D, COVID-19, SARS-COV-2 and coronavirus 2. With this search, 32 articles were finally selected for this purpose and their results were reviewed Results: Of the 32 studies reviewed, only three showed no association between vitamin D levels in the blood and COVID-19 disease. Other studies had a relationship between the severity of the disease, mortality rate and length of hospital stay, in different age, gender and location groups. Conclusion: It seems that the level of vitamin D in the blood has a potential effect on COVID-19 disease. Checking the serum vitamin D levels and supplementation in people with hypovitaminosis D can be a good solution to reduce the complications and problems caused by COVID-19.