This study analyzed human serum samples from individuals across different stages of glycemic control, including normal glucose tolerance (NGT, n=25), isolated insulin resistance (IR, n=19), IR with impaired glucose regulation (IGR, n=32), and IR with type 2 diabetes mellitus (T2DM, n=33). Untargeted metabolomics was performed using UPLC-HRMS. The data are intended for the characterization of metabolic changes along this disease spectrum. Detailed results will be reported in a future publication.