[generalenvelope]

Lots of people here are assuming that supplementing vitamin D will "treat" a low level of it, which isn't necessarily true. The level might not change, but you also might care a lot less than you think about the level specifically. Many problems can cause the level to be low, and won't be affected by raising it. Highly recommend the Barbell Medicine podcast on Vitamin D: https://soundcloud.com/user-344313169/vitamin-d-mixdown-1

[dennis_jeeves1]

Your's is the correct answer, in this case there is confusion between causation and correlation.

To make matters more confusing, vitamin D indeed produce positive results for the affiliation in the short term, for some cases.