Ah, the vitamin D deficiency panic. I remember it well, having been told a few years ago to start taking supplements right away or risk god knows what. I ignored the directive.
Think of all the pointless money and D‘ed up piss I could have passed since then!
And: Read and learn.
The larger picture.
Oh – and not to be a broken record, but if you want to be Vitamin D deficient, here’s a really good way to get there.