Figure 10. Schematic diagram illustrating RYGB and SG and the mechanisms leading to weight loss and resolution of comorbidities. For every mechanism the effect of the procedure is represented with a “” when stimulating or “” when suppressing. A “+” means that the proposed mechanism is present only after surgery when compared to the pre-operative period. When the effect is stronger for one of the two procedures there is a double arrow compared with a single one. When the effect is missing for one procedure it means that the mechanism is procedure specific. Abbreviations: RYGB, Roux-en-Y gastric bypass; SG, Sleeve gastrectomy; GLP-1, glucagon-like peptide 1; PYY3-36; peptide tyrosine-tyrosine 3-36; GIP, gastric inhibitory polypeptide; FGF-19, fibroblast growth factor-19, CCK; cholecystokinin.