That’s the obvious question that’s specifically raised as unanswered in all of these studies. But given the risks of supplementing vitamin D are about as close

That’s the obvious question that’s specifically raised as unanswered in all of these studies. But given the risks of supplementing vitamin D are about as close to zero as you can get it seems likely it’s worth the gamble that it’s a causal link. If you’re right, various severely beneficial health effects and potentially protection from one cause of death. If you’re wrong... fewer beneficial health effects?