At the end of June 2020, various news outlets reported that taking vitamin D has no benefit for COVID-19. To see this for yourself, do an internet search with the following phrase: no evidence to support vitamin D for COVID-19. You will see that multiple articles appear in America and in the UK. The information originated in the National Health Service in the UK from the National Institute for Health Care Excellence.
Only 400 IUs of supplemental vitamin D was used, which is a non-physiologic dose. In other words, taking 400 IU is essentially taking NOTHING. So we should not be surprised that it has NO beneficial effect.
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