Interestingly, we found that the serum level of 25(OH)D3 in T2D was significantly reduced as BMI increased, and it was negatively correlated with the levels of TNF-α and IFN-γ from circulating γδ T cells, indicating the therapeutic potential of vitamin 25(OH)D3 in controlling T cell inflammatory responses. Here, IFNG is linked to type 2 diabetes mellitus.