Based in large part on these two previous published human studies, the current study was designed to assess potential mechanisms by which BPA is linked with type 2 diabetes, using gold standard measures of hepatic glucose production (via [6,6-2H] glucose infusion) and skeletal muscle insulin sensitivity (via euglycemic hyperinsulinemic clamp technique), and will explore the fecal microbiome. This evidence concerns the gene INS and type 2 diabetes mellitus.