https://www.advisory.com/en/daily-br...1/14/vitamin-d

Many older people and those with compromised immune systems are NOT outdoors, exercising etc and getting even a little sun. Older folks who are robust that's another story. I listen to several MD's daily and the Vit D deficiency is horrible, covid or not. If you have not had labs done, good thing to do.

I spent 4.5 months in rehabs for knee issue some yrs back and I saw a lot of older people and I'd bet $$$ all pretty much Vit D deficient.