BEST-D: Biochemical Efficacy and Safety Trial of Vitamin D — Clinical Trial Service Unit & Epidemiological Studies Unit (CTSU)
10,000 IU vitamin D daily is safe, toxicity start at 150 ng (for monotherapy)– Jan 2013 | VitaminDWiki
200 IU needed to increase vitamin D levels by 1 ng (not 100 IU) – summary of 25 studies – Feb 2014 | VitaminDWiki
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Association between vitamin D supplementation and COVID-19 infection and mortality | Scientific Reports
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