The MS sufferer I know spent her childhood outdoors on horseback in sunny So. Cal. She came down with it around age 19. I doubt vitamin D has anything to do with it. I’m going with a virus theory. That would fit with pockets of outbreaks, and people in the same family more likely to be affected, though perhaps differently, due to proximity. My friend’s brother became schizophrenic within roughly that same age, as many schizophrenics do. Maybe hormonal development kicks it into action? idk, but my speculation is as good as anybody else’s.
Interesting.
I remember the LSM going after Mitt Romney's wife as entitled for her horseback riding.
She said it's therapy for her MS.