GCG and type 2 diabetes mellitus: Postabsorptive GLP-1 concentrations did not differ at t = 0 between obese T2D (4.0 [2.0, 4.5] pmol/L and 8.0 [5.0, 12.0] in RYGB and SG, respectively) and the healthy control subjects (7.0 [4.0, 11.0] pmol/L, p = 0.160) and remained unaltered in all groups during the OGTT.