The gut hormones and their roles in obesity and gastric restrictive surgery

Bariatric surgery procedures have become very popular in recent years for the treatment of severe obesity and its comorbid disorders, such as insulin-resistant type 2 diabetes mellitus. Various procedures have been designed to either induce malabsorption or drastically restrict the gastric reservoir and thereby inhibit food intake. However, it has become clear that other factors, such as reduced appetite and changes in energy expenditure, act in concert to induce weight loss and maintain a lower body mass. It is likely that altered release of various hormonal peptides from the alimentary tract may be involved in these adaptive functions. A better understanding of the contributions of changes in the individual hormones after bariatric surgery may enable the development of more effective surgical procedures or, alternatively, drugs that will target specific receptors to enhance weight loss. Advances in this field are likely to have a major impact on obesity and its related health problems.