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BACKGROUND/OBJECTIVES: There is considerable variation in the amount of weight patients lose after gastric bypass surgery, and this may be related to the way they adjust to the operation in their daily eating practices. Little is known about how this varies. On the basis of a qualitative research design, this study therefore explores how patients deal with gastric bypass surgery in their daily lives. SUBJECTS/METHODS: The study is based on interviews with 24 men and women in Denmark diagnosed with morbid obesity who have had, Roux-en-Y gastric bypass surgery. The interviews were transcribed, coded and analysed using 'grounded theory' methodology. RESULTS: Three strategies used by patients to cope with postoperative changes were identified. In the first strategy, patients treat surgery as time-out, using the operation to facilitate a change in their ordinary habits of daily life, but not as a solution to overweight in itself. Patients adopting the second strategy of surgery as solution would expect their smaller stomach to hinder excess food intake automatically. The third strategy of abstaining was adopted by patients who were afraid to experience negative side effects, or who believed they might 'ruin the operation'. CONCLUSIONS: Patients adjust to their postoperative condition in very different ways. The variation in the ways patients comprehend and cope with the operation and in its effects on their eating routines and practices needs to be further investigated and compared more systematically with the outcomes of the operation in terms of weight loss and overall well-being. European Journal of Clinical Nutrition (2016) 70, 523-527; doi:10.1038/ejcn.2015.212; published online 23 December 2015, INTRODUCTION Gastric bypass surgery is an effective individual treatment of morbid obesity; postoperatively, patients can expect to lose 25-35% of their total weight within 12-18 months. (1,2) Nevertheless, the evaluation [...]

Glycemic disorders resolve following Roux-en-Y gastric bypass (RYGB) surgery, but early and longer-term mechanisms regarding effects on [beta]-cell dysfunction as well as relationships with decreasing adiposity are not well understood. We evaluated longitudinal changes in peripheral insulin sensitivity (Si), the acute insulin response to glucose (AIRg), and the composite estimate of [beta]-cell function, the disposition index (DI), over 24 mo via frequently sampled intravenous glucose tolerance testing in severely obese women who had fasting normoglycemia (n = 16) and hyperglycemia (n = 11) before RYGB surgery; homeostatic model assessment (HOMA-IR) estimated insulin resistance; air displacement plethysmography determined adipose tissue mass. At baseline, subjects with normoglycemia had adequate DI associated with elevated AIRg, but DI was markedly reduced in subjects with hyperglycemia. Within 1-6 mo post-RYGB, glycemic control was normalized in subjects with hyperglycemia related to reduced HOMA-IR (-54% at 1 mo, P < 0.005) and increased DI (23-fold at 6 mo vs. baseline, P < 0.05). Over 24 mo, DI improved in subjects with hyperglycemia (15-fold vs. baseline, P < 0.005) and also modestly in subjects with normoglycemia (58%, P < 0.05), due largely to increased Si. Decreasing adiposity correlated with longer-term HOMA-IR and Si values at 6 and 24 mo, respectively. In patients exhibiting fasting hyperglycemia before surgery, [beta]-cell function improved early following RYGB, due largely to increases in insulin secretion. For both normoglycemic and hyperglycemic subjects, further improvement or stabilization of [beta]-cell function over the 2 yr is due largely to improved Si associated with reduced adiposity. disposition index; weight loss; adipose tissue mass doi: 10.1152/ajpendo.00405.2010.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jada.2009.12.023 Byline: Lauren M. Beckman, Tiffany R. Beckman, Carrie P. Earthman Abstract: Roux-en-Y gastric bypass is a well-accepted tool for the treatment of obesity and, compared to conventional weight loss methods (eg, diet and exercise) and other weight loss surgeries (eg, gastric banding), it results in considerable weight loss that is maintained long term. Although successful, the mechanisms for weight loss are not completely understood and it is thought that gastrointestinal hormones play a role. Several gastrointestinal hormones have been identified for their effects on appetite, including glucagon-like peptide-1 (GLP-1), peptide tyrosine-tyrosine (PYY), leptin, and ghrelin. This review encompasses a literature search that included 45 primary articles and shows that there are alterations in GLP-1, PYY, leptin, and ghrelin postoperatively. GLP-1 and PYY concentrations were usually found to be higher, whereas ghrelin levels were typically lower post- Roux-en-Y gastric bypass than in individuals with obesity, those who were overweight or of normal weight, and in those who underwent procedures other than Roux-en-Y gastric bypass or who achieved weight loss by lifestyle modification. An understanding of how gastrointestinal hormones change after Roux-en-Y gastric bypass may help dietetics practitioners optimize nutrition care for this patient population. A review of the literature also highlighted some research gaps that should be taken into consideration when designing future studies. Article History: Accepted 8 June 2009 Article Note: (footnote) Meets Learning Need Codes 5000, 5370, and 5390. To take the Continuing Professional Education quiz for this article, log in to ADA's Online Business Center at www.eatright.org/obc, click the "Journal Article Quiz" button, click "Additional Journal CPE Articles," and select this article's title from a list of available quizzes.

Gastric bypass surgery efficiently and lastingly reduces excess body weight and reverses type 2 diabetes in obese patients. Although increased energy expenditure may also play a role, decreased energy intake is thought to be the main reason for weight loss, but the mechanisms involved are poorly understood. Therefore, the aim of this study was to characterize the changes in ingestive behavior in a rat model of Roux-en-Y gastric bypass surgery (RYGB). Obese (24% body fat compared with 18% in chow-fed controls), male Sprague-Dawley rats maintained for 15 wk before and 4 mo after RYGB or sham-surgery on a two-choice low-fat/high-fat diet, were subjected to a series of tests assessing energy intake, meal patterning, and food choice. Although sham-operated rats gained an additional 100 g body wt during the postoperative period, RYGB rats lost ~100 g. Intake of a nutritionally complete and palatable liquid diet (Ensure) was significantly reduced by ~50% during the first 2 wk after RYGB compared with sham surgery. Decreased intake was the result of greatly reduced meal size with only partial compensation by meal frequency, and a corresponding increase in the satiety ratio. Similar results were obtained with solid food (regular or high-fat chow) 6 wk after surgery. In 12- to 24-h two-choice liquid or solid diet paradigms with nutritionally complete low- and high-fat diets, RYGB rats preferred the low-fat choice (solid) or showed decreased acceptance for the high-fat choice (liquid), whereas sham-operated rats preferred the high-fat choices. A separate group of rats offered chow only before surgery completely avoided the solid high-fat diet in a choice paradigm. The results confirm anecdotal reports of 'nibbling' behavior and fat avoidance in RYGB patients and provide a basis for more mechanistic studies in this rat model. obesity; diabetes; bariatric surgery; high-fat diet; food preference; meal patterns; satiety ratio doi: 10.1152/ajpregu.00343.2009.

The metabolic effects of Roux-en-Y gastric bypass (RYGB) are caused by postsurgical changes in gastrointestinal anatomy affecting gut function. Glutamine is a critical gut nutrient implicated in regulating glucose metabolism as a substrate for intestinal gluconeogenesis. The present study examines the effects of obesity and RYGB on intestinal glutamine transport and metabolism. First, lean and obese Zucker rats (ZRs) were compared. Then the effects of RYGB and sham surgery with pair feeding (PF) in obese ZRs were studied. Segments of small intestine (biliopancreatic limb, Roux limb, and common channel) mucosa were harvested and brush border membrane vesicles (BBMVs) were isolated on postoperative day 28. Glutamine transporter activity and abundance, [B.sup.0]AT1 protein, and mRNA levels were measured. Levels of glutaminase, cytosolic phosphoenolpyruvate carboxykinase (PEPCK-C), and glucose-6-phosphatase (G6Pase) were measured to assess glutamine metabolism and intestinal gluconeogenesis. Obesity increased glutamine transport and [B.sup.0]AT1 expression throughout the intestine. RYGB increased glutamine transport activity in the biliopancreatic (3.8-fold) and Roux limbs (1.4-fold) but had no effect on the common channel. The relative abundance of [B.sup.0]AT1 mRNA and protein were increased in the biliopancreatic (6-fold) and Roux limbs (10-fold) after RYGB (P < 0.05 vs. PF), but not the common channel. Glutaminase levels were increased, whereas the relative abundance of PEPCK-C and G6Pase were decreased in all segments of intestine after RYGB. RYGB selectively increased glutamine absorption in biliopancreatic and Roux limbs by a mechanism involving increased [B.sup.0]AT1 expression. Post-RYGB glutaminase levels were increased, but the reductions in PEPCK-C and G6Pase suggest that RYGB downregulates intestinal gluconeogenesis. obesity; gluconeogenesis; [B.sup.0]AT1; diabetes

Recent evidence suggests that the microbial community in the human intestine may play an important role in the pathogenesis of obesity, We examined 184,094 sequences of microbial 16S rRNA genes from PCR amplicons by using the 454 pyrosequencing technology to compare the microbial community structures of 9 individuals, 3 in each of the categories of normal weight, morbidly obese, and post-gastric-bypass surgery. Phylogenetic analysis demonstrated that although the Bacteria in the human intestinal community were highly diverse, they fell mainly into 6 bacterial divisions that had distinct differences in the 3 study groups. Specifically, Firmicutes were dominant in normal-weight and obese individuals but significantly decreased in post-gastric-bypass individuals, who had a proportional increase of Gammaproteobacteria. Numbers of the [H.sub.2]-producing Prevotellaceae were highly enriched in the obese individuals. Unlike the highly diverse Bacteria, the Archaea comprised mainly members of the order Methanobacteriales, which are [H.sub.2]-oxidizing methanogens. Using real-time PCR, we detected significantly higher numbers of [H.sub.2]-utilizing methanogenic Archaea in obese individuals than in normal-weight or post-gastric-bypass individuals. The coexistence of [H.sub.2]-producing bacteria with relatively high numbers of [H.sub.2]-utilizing methanogenic Archaea in the gastrointestinal tract of obese individuals leads to the hypothesis that interspecies [H.sub.2] transfer between bacterial and archaeal species is an important mechanism for increasing energy uptake by the human large intestine in obese persons. The large bacterial population shift seen in the post-gastric-bypass individuals may reflect the double impact of the gut alteration caused by the surgical procedure and the consequent changes in food ingestion and digestion. methanogen | microbial community | syntrophy | pyrosequencing | microbiome

Long term risk of death after bypass surgery was determined. Results concluded reduction in disease related death as well as increase in non disease related death after gastric bypass surgery.

The rates and indications for inpatient hospital use before and after Rouxen-Y gastric bypasses ((RYGB) is determined. Increases in hospital use after surgery appear to be related to RYGB and hence payers, clinicians and patients must consider the not-inconsequential rate of rehospitalization after this type of surgery.

Gastric-bypass surgery can curb obesity as well as diabetes and a slew of other problems. Researchers are now trying to find out how it works. Every week, about 20 people [...]

Bariatric surgery or gastric bypass surgery in patients with morbid obesity helps, in addition to weight reduction, to resolve comorbid conditions such as type 2 diabetes, hypertension, hyperlipidemia and sleep apnea. However, questions are being raised regarding the safety and effectiveness of the surgery.

Health benefits persist years after procedure. Health benefits persist years after procedure., Author Affiliations: An X-ray shows the shrunken gastrointestinal tract resulting from a gastric bypass, an operation that can help obese people to lose weight. Credit: Zephyr/SPL An X-ray shows the [...]