> but if your vitamin D level is OK then you might be less likely to end up in an hospital or even in intensive care
But only as a form of correlation not necessary causation.
Which means if you make sure you don't have low vitamin D levels because you heard it is correlated with COVID your likelihood of having worse COVID systems might not change at all!
Becau you might have "something" which makes worse COVID systems more likely which also happens to cause low vitamin D levels. Or you might have something caused by your living habits which also makes low vitamin D levels more likely.
I.e. as far as I know studies could only find statistic relevance for correlation (in some cases) but no statistic relevance for causation.
Idk, but it might literally be as simple as unhealthy older people being more likely to have vitamin D deficit and also being more likely to have worse COVID syntoms.
If you ignore the extensive literature describing vitamin D's multi-pronged involvement in metabolism then your final sentence is entirely reasonable. Here's a very short summary of some of the effects whereby vitamin D may may be causatively involved in the strongly demonstrated (there are numerous accounts in the literature) inverse relationship between vitamin D levels and the severity of COVID infection. Incidentally the focus should be not on how much vitamin D is taken as a supplement but on the actual blood level. Tons of references on what this should be rather my quoting those levels here.
Thanks, I realized myself that what I wrote is flawed.
Even ignoring the literature you linked and just using common sense having a deficit puts a burden on your body and any additional burden when fighting some illness makes the fight harder. (Well, ok, there are some exceptions, humans are complex.).
But only as a form of correlation not necessary causation.
Which means if you make sure you don't have low vitamin D levels because you heard it is correlated with COVID your likelihood of having worse COVID systems might not change at all!
Becau you might have "something" which makes worse COVID systems more likely which also happens to cause low vitamin D levels. Or you might have something caused by your living habits which also makes low vitamin D levels more likely.
I.e. as far as I know studies could only find statistic relevance for correlation (in some cases) but no statistic relevance for causation.
Idk, but it might literally be as simple as unhealthy older people being more likely to have vitamin D deficit and also being more likely to have worse COVID syntoms.