We know that Vitamin D is essential in regulating the amount of calcium and phosphate in our body. But can it also help in fighting the COVID-19 infection? Recent researches by scientists in the US and the UK seems to suggest so. A study of global data showed a clear association between severe vitamin D deficiency and high COVID-19 mortality rates. The team was trying to understand the reason behind unexplained differences in COVID-19 mortality rates between different countries. 
The aim of the study was to investigate if Vitamin D played any role in COVID-19 progression. This included complications that could range from unregulated inflammation to mortality. They analyzed data from hospitals in China, Italy, Spain, France, Germany, Switzerland, Iran, South Korea, the United Kingdom, and the United States. The team found that countries with high COVID-19 mortality rates, such as the UK and Spain also saw patients with lower Vitamin D levels when compared to countries not as severely affected.
Subsequently, the researchers found a strong correlation between Vitamin D levels and cytokine storm, which is a hyperinflammatory condition which is caused by an overactive immune system. Vitamin D stops the immune system from becoming hyperactive. This could also explain why children, who do not have a fully developed immune system, have a lower mortality rate.
However, researchers cautioned against the hoarding of Vitamin D, asking for more research. These observations were echoed in another study by scientists in the UK. Published in the Irish Medical Journal, the study focused on vitamin D levels in European countries, cross-checking it with COVID-19 infection and mortality data. The authors made a strong appeal to national and international health bodies for optimizing their Vitamin D recommendations.
COVID-19 is an emerging, rapidly evolving situation.
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