Physiology of Weight Loss Surgery
Section snippets
Why (are people so fat?)
Several hypotheses and theories have been introduced to explain the origins of the current obesity epidemic. In 1962, a geneticist by the name of James V. Neel1 presented his theory of how the progress of natural human evolution favored the perpetuation of obesity and diabetes promoting “thrifty genes.”1 He proposed that those individuals who had thrifty genes were better able to extract nutrients from ingested food and were more efficient in accumulating fat during times of abundance, and this
How (does it all work?)
One of the earliest studies reporting on the effectiveness of surgery in treating obesity-related diseases (ie, diabetes) was first published in 1955. In this study, Friedman and colleagues9 reported observing “the amelioration of diabetes mellitus following subtotal gastrectomy.” Several decades later, Pories and colleagues10 reviewed their experience with gastric bypass surgery performed on obese patients and showed effective and durable weight loss (in a 14-year period) along with an 83%
Summary
Although the root cause of the current obesity epidemic has not been discovered, it warrants considerable attention and the appropriate use of all the treatment options available. As shown in Fig. 1, bariatric surgery is a proven and unrivaled treatment of obesity and the management of obesity-related diseases. Gastric bypass produces profound physiologic and metabolic changes in many organs as a result of surgical anatomic manipulation, as shown by the many studies available in the literature.
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Cited by (24)
Evidence for Neurocognitive Improvement After Bariatric Surgery: A Systematic Review
2017, PsychosomaticsCitation Excerpt :BS is more effective than medical treatment and lifestyle interventions for moderate and severe obesity, both in short- and long-term follow-up studies.51,52 Potential mechanisms for BS-related weight loss have included hypotheses related to changes in leptin, ghrelin, and insulin sensitivity.53,54 In general with weight loss, regardless of the method by which it is achieved, leptin levels seem to increase and there is some evidence that obese subjects may regain some leptin sensitivity, changing their neural response to food.45,53
Metabolic Predictors of Weight Loss After Bariatric Surgery
2017, Metabolism and Pathophysiology of Bariatric Surgery: Nutrition, Procedures, Outcomes and Adverse EffectsAdjustable gastric banding, sleeve gastrectomy or gastric bypass. Can evidence-based medicine help us to choose?
2013, Journal of visceral surgeryGastric banding, sleeve gastrectomy or gastric bypass. Is evidence-based medicine able to help us making our choice?
2013, Journal de Chirurgie Viscerale
Dr Alfonso Torquati is supported by National Institute of Health grant K23 DK075907.