Fig. 2.

Schematic illustration of potential physiological mechanisms after bariatric surgery. Different mechanisms are arranged on the basis of their level of origin and, therefore, divided into gastrointestinal effects (inner circle, light gray), systemic effects (middle circle, medium gray) and behavioral effects (outer circle, dark gray). Borders between the three levels are transient. Arrows and connections between mechanisms have been intentionally omitted to avoid implication of causal relationships, which in many cases have not yet been established. References are given in parentheses for each mechanism. For further details, please see text.