COVID-19 and Vitamin D
The link between COVID-19 severity and Vitamin D deficiency has been demonstrated in scientific literature. It is believed that having adequate levels of vitamin D (cholecalciferol) lessens COVID-19 severity, as well as the chance of death. A deficiency in vitamin D levels has been linked to more severe COVID-19 cases, as well as greater chance of death from the disease. For example, a meta analysis in Iran of studies involving nearly 5,000 participants found that "the mean serum 25-hydroxyvitamin D level was low in all COVID-19 patients, and most of them were suffering from vitamin D deficiency/insufficiency." 
In small study published in the British Medical Journal in November 2020, a COVID-19 infected group which was deficiency in Vitamin D was given a massive dose of 60,000 IUs in Vitamin D daily for seven days (the "intervention group") with significant success. The results were that "10 (62.5%) participants in the intervention group and 5 (20.8%) participants in the control arm (p<0.018) became SARS-CoV-2 RNA negative."
Liberal media outlets that falsely attacked hydroxychloroquine have also argued against the strong link between Vitamin D and the virus. This is likely to hype up remdesivir which has been shown in clinical trials not to reduce mortality.
Recommended prophylactic dosage in anticipation of exposure to COVID-19 is 5,000 IU per day, which is higher than the 2,000 IU per day dosage on many Vitamin D products.
Dietary sources of Vitamin D
Sources of Vitamin D in food include:
- dairy products
- chicken breasts
- oily fish, including tuna, trout, and mackerel
- portobello mushrooms
- beef liver
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