The pathway of how vitamin D functions have also been discussed a lot and recent studies have demonstrated that the vitamin D level influences on the level of pro-inflammatory cytokines (IL-6 and TNF-α) as well as the activity of T and B cells, which explains why vitamin D could contribute to hip fracture not only from calcium absorption but also from modulating inflammation and immune function [37,39]. This evidence concerns the gene IL6 and hip fracture.