Obesity surgery remains the most effective treatment for obesity and its complications.
Weight loss was initially attributed to decreased energy absorption from the gut but
have since been linked to reduced appetitive behaviour and potentially increased
energy expenditure. Implicated mechanisms associating rearrangement of the
gastrointestinal tract with these metabolic outcomes include central appetite control,
release of gut peptides, change in microbiota and bile acids. However, the exact
combination and timing of signals remain largely unknown. In this review, we survey
recent research investigating these mechanisms, and seek to provide insights on
unanswered questions over how weight loss is achieved following bariatric surgery
which may eventually lead to safer, nonsurgical weight-loss interventions or
combinations of medications with surgery