Interesting blog:

Vitamin D vrs Acute Respiratory Infections

Very much worth watching, at least the first part. The whole thing is very interesting, if a bit repetitive. It's about a study of studies across many different experiments with Vitamin D supplements. It offers substantial protection from respiratory infections like the ones that Covid-19 gives seriously ill and dying patients.

A lot of the deaths occur not so much because of the virus, but because of the immune response that fills the lungs with fluid. Vitamin D mutes that response. It actually mutes a lot of different inflammatory responses, so it is useful for all sorts of autoimmune diseases. I'm taking about 8000 iu/day for my MS. The doctor blogging is taking about 1000 iu/day. You all should be too!

He says a lot of us are D deficient, and by taking supplements it decreases your respiratory infections by 70%! (But don't go crazy with it: Too much is not healthy.)