Abstract
Over 7 million people died of COVID-19 globally in the current pandemic. Westernised countries reported increased COVID-19 illness with increased mortality rates in their South Asian and Black communities, while dark-skinned communities are more severely vitamin D deficient than others in westernised countries. Vitamin D has many proven mechanistic effects protective against infections and against the ‘acute respiratory distress syndrome’ that caused many COVID-19 deaths. This ‘commentary’, therefore, considers prospective evidence for reductions in COVID-19 risks with better vitamin D repletion; whether treating deficiency reduces COVID-19 risks, and discusses the many actions of vitamin D that could lead to such risk reductions.
Better pre-pandemic vitamin D status predicted ~50% COVID-19 risk reductions in each US state [in ~400,000 adults] and in health care staff. Governments generally resisted calls for higher vitamin D intakes [at 1000-2000 IU/day], quoting ‘lack of randomised controlled trials’, and fear of vitamin D ‘toxicity’, despite safe unsupervised population intake generally advised being ‘up to 4000 IU/day’. The UK has since recommended daily adult intakes of 400 IU/day, helpful, but too small to correct deficiency. American rules on ‘medical need’ meant banning treatment of COVID-19 with vitamin D so that the new mRNA vaccines could be used. More recently, trials treating COVID-19 illness with vitamin D3 [at 1,000,000 IU over 2 weeks] or with the vitamin D 25(OH)D metabolite, calcifediol [at ~2.0mg over 1 month] have shown significantly reduced Covid-19 severity and mortality. This information makes a cogent case for ensuring vitamin D sufficiency globally, most especially in dark skinned communities, as a cost-effective measure for reducing the risks from future COVID-19 variants and from the future health risks of newly emergent pathogenic viruses.