The UK Government agency tasked with undertaking a rapid evidence summary of vitamin D’s potential role in reducing the risks from Coronavirus has concluded that there is “no evidence to support taking vitamin D supplements to specifically prevent or treat COVID‑19”.
Researchers at the National Institute for Health and Care Excellence (NICE) reviewed five relevant observational studies (D’Avolio et al. 2020 , Hastie et al. 2020 , Ilie et al. 2020 , Laird et al. 2020 and Fasano et al. 2020), noting that none were intervention trials of vitamin D supplementation for the prevention or treatment of COVID‑19.
The agency concluded that all five studies had a “high risk of bias because of “the very low quality of evidence”, and that no causal relationship could be established after adjustment for confounders such as comorbidity, socio-demographics, ethnicity, BMI and other baseline factors.
A separate rapid review, conducted by the Scientific Advisory Commission on Nutrition (SACN), assessed evidence on vitamin D and acute respiratory tract infections (ARTIs), although it did not look specifically at the effect of vitamin D supplementation on COVID-19 risk). This review also concluded that evidence currently does not support vitamin D supplementation to prevent ARTIs in the general UK population.
Both agencies continue to support UK Government advice that, during the COVID‑19 pandemic, everyone should should consider supplementing with vitamin D due to extended periods indoors during lockdown. SACN noted that its review “reiterates the importance of vitamin D for bone and muscle health”.