Ha, good luck finding Vitamin D en masse... however, I do have a treat for you (Israeli study too!):
https://www.medrxiv.org/content/10.1101/2021.06.04.21258358v1.full.pdf
The TL;DR of it is this:
So long as your Vit-D is above 20, you're a lot more protected.
HOWEVER:
Vitamin D deficiency was associated with ...
comorbidities including COPD (Chronic obstructive pulmonary disease) (p=0.006),
diabetes (p=0.026),
and hypertension (p =0.016)
In other words, people with low Vit-D levels were fucked to begin with.
The optimist in me wants to believe that low Vit-D levels are responsible for general system vulnerability - the easy solution then, is to get more Vit-D.
The scientist/realist in me understands that most likely, we're talking about people with an unhealthy background, which expresses itself in many ways, including low Vit-D.
Thanks for finding the data, reading through the pdf now. In Israel which is a warm and normally sunny climate I'd assume have higher levels of Vitamin D among the population than let's say England which led me to bring this up. So what I was getting at is could this be skewing the figures.
And the worst Vitamin D levels are in racial minorities living outside their home latitudes where skin colour drastically affects natural levels.
Also plenty of evidence that over 60 the natural creation of Vitamin D really drops off. I have my parents here in Israel supplementing quite a bit.
You'd think so, wouldn't you??
Apparently we've for the most part become so Westernised that we stay indoors most of the time, so the sun's there, we're just not taking it in.
I've also heard claims that Vit D takes time to absorb after exposure - that showering up to 24h (or 48?) after being in the sun reduces intake by a lot. Let's just say people aren't walking around soaking up sunrays and then not hitting the showers here.
But this is just stuff I've heard, I can't vouch for any of the claims.