Existing epidemiologic and clinical studies have demonstrated that obesity is associated with the risk of a variety of cancers. In recent years, an increasing number of experimental and clinical studies have unraveled the complex relationship between obesity and cancer risk and the underlying mechanisms. Obesity-induced abnormalities in immunity and biochemical metabolism, including chronic inflammation, hormonal disorders, dysregulation of adipokines, and microbial dysbiosis, may be important contributors to cancer development and progression. These contributors play different roles in cancer development and progression at different sites. Lifestyle changes, weight loss medications, and bariatric surgery are key approaches for weight-centered, obesity-related cancer prevention. Treatment of obesity-related inflammation and hormonal or metabolic dysregulation with medications has also shown promise in preventing obesity-related cancers. In this review, we summarize the mechanisms through which obesity affects the risk of cancer at different sites and explore intervention strategies for the prevention of obesity-associated cancers, concluding with unresolved questions and future directions regarding the link between obesity and cancer. The aim is to provide valuable theoretical foundations and insights for the in-depth exploration of the complex relationship between obesity and cancer risk and its clinical applications.
Humans ; Adipokines/metabolism* ; Bariatric Surgery ; Inflammation/therapy* ; Neoplasms/prevention & control* ; Obesity/therapy* ; Risk Factors

Roux-en-Y gastric bypass and laparoscopic sleeve gastrectomy characterized by simple operation and few postoperative complications have gradually become the two most commonly used surgical methods in clinical practice.A series of complications often occur after bariatric surgery,including gallstone disease,anemia,malnutrition,gastroesophageal reflux disease,kidney stones,and birth defects in offspring of women of childbearing age.There are controversies regarding the causes and countermeasures of these complications.This article mainly reviews the risk factors and countermeasures for the complications after bariatric surgery.
Humans ; Female ; Bariatric Surgery/methods* ; Gastric Bypass/methods* ; Gastroesophageal Reflux/surgery* ; Postoperative Complications/prevention & control* ; Risk Factors ; Gastrectomy/methods* ; Laparoscopy/methods* ; Obesity, Morbid/surgery* ; Retrospective Studies

With the increasing number of obese patients worldwide, metabolic and bariatric surgery (MBS) has quickly become an effective way to treat obesity and related metabolic diseases such as type 2 diabetes, hypertension, lipid abnormalities, etc. Although MBS has become an important part of general surgery, there is still controversy regarding the indications for MBS. In 1991, the National Institutes of Health (NIH) issued a statement on the surgical treatment of severe obesity and other related issues, which continues to be the standard for insurance companies, health care systems, and hospital selection of patients. The standard no longer reflects the best practice data and lacks relevance to today's modern surgeries and patient populations. After 31 years, in October 2022, the American Society for Metabolic and Bariatric Surgery (ASMBS) and the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO), the world's leading authorities on weight loss and metabolic surgery, jointly released new guidelines for MBS indications, based on increasing awareness of obesity and its comorbidities and the accumulation of evidence of obesity metabolic diseases. In a series of recommendations, the eligibility of patients for bariatric surgery has been expanded. Specific key updates include the following: (1) MBS is recommended for individuals with BMI≥35 kg/m², regardless of the presence, absence, or severity of co-morbidities; (2) MBS should be considered for individuals with metabolic diseases and BMI 30.0-34.9 kg/m²; (3) the BMI threshold should be adjusted for the Asian population:: BMI≥25 kg/m² suggest clinical obesity, and BMI ≥ 27.5 kg/m² population should consider MBS; (4) Appropriately selected children and adolescents should be considered for MBS.
Adolescent ; Child ; Humans ; Diabetes Mellitus, Type 2/surgery* ; Bariatric Surgery ; Obesity/surgery* ; Obesity, Morbid/surgery* ; Weight Loss

Objective: Obesity is known to be associated with left ventricular diastolic dysfunction due to its effect on blood pressure and glucose tolerance. We aimed to investigate whether weight loss after bariatric surgery might improve diastolic dysfunction through in-depth echocardiographic examination. Methodology: We recruited twenty-eight patients who were about to undergo bariatric surgery by purposive sampling. They underwent echocardiography at baseline and 6 months after surgery with a focus on diastolic function measurements and global longitudinal strain (GLS). They also had fasting serum lipid and glucose measurements pre- and post-surgery. Results: The mean weight loss after surgery was 24.1 kg. Out of the 28 subjects, fifteen (54%) initially had diastolic dysfunction before surgery. Only two had persistent diastolic dysfunction 6 months after surgery. The mean indexed left atrial volume 6 months post-surgery was 27.1 from 32 ml/m2 prior to surgery. The average E/e’ is 11.78 post-surgery from 13.43 pre-surgery. The left ventricular GLS became (-)25.7% after surgery from (-)21.2% prior to surgery. Their post-surgery fasting serum lipid and glucose levels also showed significant improvement. Conclusion Our study reinforced the existing evidence that bariatric surgery significantly improved echocardiographic parameters of diastolic function and left ventricular global longitudinal strain, along with various metabolic profiles.
Bariatric Surgery ; Obesity

The rising prevalence of obesity in Singapore is a harbinger for a corresponding increase in obesity-related complications such as type 2 diabetes mellitus (T2DM) and coronary heart disease. Obesity is a complex disease driven by multiple factors, and hence, treatment cannot follow a 'one-size-fits-all' approach. Lifestyle modifications involving dietary interventions, physical activity and behavioural changes remain the cornerstone of obesity management. However, similar to other chronic diseases such as T2DM and hypertension, lifestyle modifications are often insufficient on their own, hence the importance of other treatment modalities including pharmacotherapy, endoscopic bariatric therapy and metabolic-bariatric surgery. Weight loss medications currently approved in Singapore include phentermine, orlistat, liraglutide and naltrexone-bupropion. In recent years, endoscopic bariatric therapies have evolved as an effective, minimally invasive and durable therapeutic option for obesity. Metabolic-bariatric surgery remains the most effective and durable treatment for patients with severe obesity, with an average weight loss of 25%-30% after one year.
Humans ; Singapore ; Diabetes Mellitus, Type 2 ; Obesity ; Obesity, Morbid ; Bariatric Surgery

Gut microbiota have been validated to play a pivotal role in metabolic regulation. As the most effective treatment for obesity and related comorbidities, bariatric surgery has been shown to result in significant alterations to the gut microbiota. Literature have recently suggested temporal and spatial features of alterations to the intestinal bacteria following bariatric surgery, which is possibly attributed to the gut adaptation to the surgical modification on the gastrointestinal tract. More importantly, the gut microbiota have been appreciated as a critical contributor to the metabolic improvements following bariatric surgery. Although not fully elucidated, the underlying mechanisms are associated with the molecular pathways mediating the crosstalk between gut microbiota and host . On the other hand, change of the gut microbiota has been found to be related to the prognosis of patients receiving bariatric surgery. Some studies even point out negative effects of the gut microbiota on certain surgical complications . In this review, we summarize the characteristics of alterations to the gut microbiota following bariatric surgery as well as its relevant impacts to better understand the role of gut microbiota in bariatric surgery.
Bariatric Surgery ; Gastrointestinal Microbiome/physiology* ; Gastrointestinal Tract ; Humans ; Obesity/surgery* ; Treatment Outcome

Bariatric-metabolic surgery (BMS) has the potential of decreasing body weight and improving obesity-related metabolic syndrome by restricting food intake and malabsorption. Laparoscopic sleeve gastrectomy, Roux-en-Y gastric bypass, adjustable gastric banding, biliopancreatic diversion with duodenal switch are four major BMS procedures. Sleeve plus surgery, one-anastomosis gastric bypass, intragastric balloon and endoscopic surgery are also arising and gaining popularity due to their specific efficacy. Currently, BMS is now experiencing an era with deeply integrated interdisciplinarity, optimizing and innovating of surgeries and well-illustrated clinical efficacy, as a result, more obese patients would benefit from BMS.
Bariatric Surgery ; Gastrectomy ; Gastric Balloon ; Gastric Bypass ; Humans ; Laparoscopy ; Morbidity ; Obesity/surgery* ; Obesity, Morbid/surgery*

With the increasing prevalence of obesity and the popularity of bariatric surgery, more and more patients with obesity are undergoing bariatric surgery. "Precision Medicine" is a new generation of medical concepts. We introduce the concept of "precision medicine" into precision bariatric and metabolic surgery, in order to optimize and integrate modern surgical theory and technology with traditional surgical methods under the requirements of high precision and high efficiency standards, so as to achieve minimal trauma and invasion, maximal organ protection, minimal medical cost and best weight loss effect. Chinese Society for Metabolic and Bariatric Surgery (CSMBS) organized some domestic bariatric surgery experts to conduct four relevant problem-oriented and 36 clinically practical problems, including precise preoperative assessment, precise perioperative management, precise surgical operation, and precise postoperative management. Based on domestic and foreign literature evidence and combined with Chinese conditions and clinical experience, CSMBS has formulated a Chinese expert consensus on precision obesity metabolic surgery, aiming to provide guidance for the clinical practice of precision obesity metabolic surgery in our country.
Bariatric Surgery ; China ; Consensus ; Humans ; Obesity/surgery* ; Weight Loss

The quantity of cases of metabolic and obesity-related diseases including obesity and type 2 diabetes in China are increasing each year. The total numbers of both existing patients and new patients each year are rated as the highest in the world. A large amount of evidence-based medical reports have shown that bariatric surgery can effectively reduce excessive body weight in patients with morbid obesity, and alleviate the effects of a series of obesity-related metabolic comorbidities, including type 2 diabetes. Laparoscopic one anastomosis gastric bypass (OAGB) is currently one of the most widely practiced bariatric surgeries procedures in the world. Although this procedure has been carried out on patients in China for more than 15 years, the standard surgical operation for OAGB has not been subject to relevant guidelines or consensus. In light of this, Chinese Society for Metabolic & Bariatric Surgery (CSMBS) recently initiated the compilation of the first edition of the "Procedural guideline for laparoscopic one anastomosis gastric bypass (2022 Edition)", aiming to provide a unified specifications for this procedure. It will provide a reference for surgical operating standards for clinicians in the field of obesity-related metabolic surgery to reduce or avoid complications caused by irregular surgery, and will ultimately benefit more patients.
Bariatric Surgery ; Diabetes Mellitus, Type 2/surgery* ; Gastric Bypass/adverse effects* ; Humans ; Laparoscopy ; Obesity, Morbid/surgery* ; Retrospective Studies

Due to the complexity and heterogeneity of obesity, the diagnosis and treatment of obesity vary greatly. Five to 10 percent of body weight can be lost through lifestyle modifications, nutritional and behavioral counseling, and the use of approved weight reduction medicines for obesity and diabetes; however, these non-surgical treatments are not effective for all patients. Compared to medical therapy, bariatric surgery is associated with higher rates of type 2 diabetes remission, lower mortality from vascular complications, and long-term, sustained weight loss. With the advent of precision medicine in surgical therapy, bariatric surgeons' fundamental understanding of laparoscopic Roux-en-Y gastric bypass surgery has evolved in recent years. The objective of surgery has shifted from short-term weight loss to the safe and successful long-term management of patient weight and comorbidities. In laparoscopic Roux-en-Y gastric bypass surgery, the concept of precision bariatric and metabolic surgery is mainly reflected in three aspects: accurate preoperative assessment, precise intraoperative operation, and comprehensive postoperative management. A new direction for the future development of precision laparoscopic Roux-en-Y gastric bypass surgery and obesity metabolic surgery is to formulate precise and individualized surgical treatment plans for patients and to use artificial intelligence and big data technology to improve the standardization of specialist data.
Artificial Intelligence ; Bariatric Surgery ; Diabetes Mellitus, Type 2/surgery* ; Gastric Bypass/adverse effects* ; Humans ; Laparoscopy ; Obesity/surgery* ; Obesity, Morbid/surgery* ; Treatment Outcome ; Weight Loss