Background: The insulin growth factor binding protein (IGFBP) – 2 is a circulating protein secreted by the liver. IGFBP-2 circulating levels are lower in patients with metabolic disorders (obesity, non-alcoholic steatohepatitis and diabetes). In 2012, we showed that, in humans, biliopancreatic diversion with duodenal switch (BPD-DS) induces a significant, rapid and sustained increase in circulating IGFBP-2 levels. In this context, we wished to further (1) compare IGFBP-2 modulation between diverse bariatric surgeries, (2) associate IGFBP-2 levels to insulin sensibility and energy metabolism improvements after surgery. Methods:Plasma IGFBP-2 concentrations were quantified in patients before and after BDP-DS, Roux-en-Y gastric bypass (RYGB), or Sleeve gastrectomy (SG). Insulin sensibility and energy metabolism were assessed using euglycemia-hyperinsulinemic clamp and PET scan (18F-FtHA) before and after BPD-DS and SG surgeries.Results: Circulating IGFBP-2 levels were raised 6-fold by BPD-DS (164±62 vs 915±323 ng/mL, p<0.0001) and levels were higher than after SG and RYGB (457±284 and 500±150 ng/mL respectively). Plasma IGFBP-2 levels were positively associated with improvement in insulin sensibility (r = 0.6724, p <0.0001), fasting glucose (r = -0.4393, p<0.001) and fasting insulin (r = -0.6071, p <0.0001). IGFBP-2 levels were also associated with early improvement in energy metabolism. Conclusion: These data demonstrate that bariatric surgery increases IGFBP-2 production but more efficiently with duodenal switch (BPD-DS). Plasma IGFBP-2 levels were positively associated with improvement in carbohydrate and energy metabolism and could thus contribute to the beneficial impacts of the surgery.