Does Vitamin D Protect Against Covid?

“Vitamin D has well-known effects in helping to fix calcium in the bones and for these reasons it is frequently prescribed to aging children and the elderly for the prevention of osteopenia. In addition, other studies carried out in Asia, exclusively on children, have also shown that vitamin D can modulate some immune functions in case of respiratory infections.
This is undoubtedly why a link between vitamin D and COVID is so widely proposed today.
However, to say that vitamin D protects against COVID seems premature to me. At this point, several medical teams around the world have found that there is more Covid + in people deficient in vitamin D. But beware of shortcuts: this statistical association in no way proves the causal link.

“No clinical studies have been conducted to demonstrate that vitamin D has a beneficial and protective effect against Covid-19”

The only way to demonstrate a causal link between vitamin D supplementation and COVID would be to conduct a large, double-blind, randomized clinical trial with two separate patient groups. However, to date, no studies have been conducted under these conditions and there is therefore nothing that definitively demonstrates that vitamin D has a beneficial and protective effect against Covid 19.
On the other hand, the statistical association so strongly pushed by some medical teams can be a confusing factor. I remind you that vitamin D deficiency can only be an indicator of poorer nutritional status and worse health in Covid patients. We are alone in the field of investigation and the massive supplementation of vitamin D in people at risk of developing a severe form of the virus does not yet seem justified. “