Also, as an important aside, African Americans and Latino Americans tend, as a population, to have the most severe Vitamin D deficiency, which may be one significant reason (of many) that those populations are being so badly affected.
The percentages of people who are testing positive for COVID19 and also those ending up in the ER with the most severe cases seems to correlate highly with Vitamin D deficiency.
Vitamin D helps regulate the immune system, particularly autoimmune reactions, and protects against respiratory infections generally. Since it is cheap and beneficial, there is really not a great deal of harm moderately supplementing Vitamin D to reduce this risk factor.
It’s not a cure, but it seems to have substantial potential beneficial effects on health overall (I had been taking it and had stopped last year) and on COVID19 related measures, it correlates well with better outcomes. Not causality, but good correlation so far. They should probably do some more definitive studies.
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