Thanks for these sources, wish I had some merit to give you.

This is stuff everybody needs to read, I'm sure 9/10 is an exeggeration.

But it's definitely a high number.

Although as I'm thinking and typing I can only imagine a lot of old people have Vit D difficiency due to absorbtion and also spending a lot of time in the house. I made my nan take some at the start of the pandemic, thankfully she's vaccinated now but I like to think I helped her!