The mechanism of weight loss with laparoscopic adjustable gastric banding: induction of satiety not restriction

The defence of body weight: a physiological basis for weight regain after weight loss

Although weight loss can usually be achieved by restricting food intake, the majority of dieters regain weight over the long-term. In the hypothalamus, hormonal signals from the gastrointestinal tract, adipose tissue and other peripheral sites are integrated to influence appetite and energy expenditure. Diet-induced weight loss is accompanied by several physiological changes which encourage weight regain, including alterations in energy expenditure, substrate metabolism and hormone pathways involved in appetite regulation, many of which persist beyond the initial weight loss period. Safe effective long-term strategies to overcome these physiological changes are needed to help facilitate maintenance of weight loss. The present review, which focuses on data from human studies, begins with an outline of body weight regulation to provide the context for the subsequent discussion of short- and long-term physiological changes which accompany diet-induced weight loss.

Metabolic-Bariatric Surgery: An Emerging Specialty

After the end of the second world war, the world saw a significant period of growth and prosperity unlike any previously. By the 1950s, morbid obesity was proving to be a clinical problem in many developed societies in Europe and North America. Diet, lifestyle and medication alone did not appear to be effective in controlling morbid obesity, and surgical interventions were developed. Surgical therapies to combat the epidemic of obesity evolved from intestinal bypasses (which had the potential for serious fluid, electrolyte and nutritional disturbances) to eventually settle on manipulations that involve restrictive procedures of the stomach with or without bypass of the duodenum and jejunum. This branch of surgery was referred to as “bariatric” (from the Greek “baros” for weight), but recent awareness that concomitant obesity-related metabolic diseases can also be effectively treated by these procedures has given rise to the new specialty of metabolic-bariatric surgery (MBS). This review looks at current MBS procedures and their impact on gastro-intestinal physiology to achieve both weight loss and metabolic control.