I’ve never talked to someone supplementing vitamin D who was aware at all.

I think that the correct approach would be start at 10x vitamin D with baseline bloodwork and adjust dosage from there.

But yeah I’m in the camp of “sun is good for you, in most cases.” I would be very unsurprised to find that there are precursor hormones released beyond vitamin D that impact efficacy. We don’t really understand the endocrine system very well.

I think that because we can see and understand the dermatological effects we overly weight them. Anecdotally older people I know who have not avoided the sun seem much better off mentally and physically, but I think because there isn’t a measurable reason we’re aware of, we completely discount any benefit.