Yet another rapid review by the UK's NICE finds insufficient evidence to support taking vitamin D to prevent or treat COVID-19. Nevertheless, the UK government is handing out free vitamin D supplements to clinically vulnerable groups in England from Janurary. 

By handing out free supplements to the clinically vulnerable, the UK government is effectively endorsing the use of vitamin D to reduce the risk and/or severity of COVID-19, although it says more research is needed.

A study with nearly 500 patients with vitamin D levels tested within a year before receiving COVID-19 tests found subjects deficient in the nutrient had 1.77 greater chance of testing positive. Researchers say RCTs are needed to determine if broad population interventions are necessary.