A recent study investigating the relationship between total bile acids, FGF19, and T2DM in bariatric surgery identified important roles of total bile acids and FGF19 in T2DM remission after sleeve gastrectomy (SG) by comparing postprandial gut hormone patterns between patients undergoing laparoscopic gastric bypass (GB) and laparoscopic sleeve gastrectomy 2 years after surgery [92]. This evidence concerns the gene FGF19 and type 2 diabetes mellitus.