While all the procedures enable speedy weight loss, it is studied and concluded that after 1 year, the LRYGB has a higher percentage of excess weight loss when compared to laparoscopic sleeve gastrectomy (LSG), 84.2 % vs. 66.1 %. At the 5-year mark, patients were able to maintain 65–70 % of excess weight loss [1]. LRYGB is effective for patients with a higher BMI due to the higher percentage of weight loss. Meta-analysis also demonstrates that LRYGB is more effective than LSG for the treatment of type 2 diabetes mellitus and metabolic syndrome [2]. Studies have shown that 90 % of patients see an improvement in their DM and high blood pressure. Patients also note that their sleep apnea no longer poses a problem, and their use of CPAP had significantly reduced [1]. There were also significant improvements in their gastric reflux and osteoarthritis. The LRYGB is also more effective for people who crave foods that are high in sugar or fat. This is directly related to dumping syndrome that occurs when such foods are consumed. This then discourages patients from eating unhealthy [3].

Although the abovementioned facts make the LRYGB appealing to many patients, the complications or disadvantages of this procedure are more severe in nature as well. Unlike gastric banding, this procedure results in permanent disruption of the anatomy. Once a patient undergoes a LRYGB, it is rarely reversed. The procedure itself is more technically challenging, which leads to longer operative time as well as longer hospital course [3]. Studies have also shown that the rates of readmission were higher in LRYGB compared to LSG. It was also noted that the initial length of stay in the hospital immediately post-op had a correlation to the readmission rate as well [4].

With multiple areas of anastomoses, the chance of a leak is increased. The anastomotic areas are also at risk for developing marginal ulcers, particularly at the jejunal side. Patients also develop strictures at their sites of anastomoses. When compared to the other weight loss procedures, LRYGB has a higher risk of internal hernias – three areas in particular are potential sites. Due to the malabsorptive nature of the procedure, patients are also at a higher risk of nutritional deficiencies such as deficit in iron, vitamin B12, iron, calcium, and folate [3]. Patients will require lifelong supplementation of vitamin and minerals as well as long-term follow-up with their surgeon and dietitian. When compared to gastric banding or sleeve gastrectomy, patients that undergo a LRYGB may experience dumping syndrome which is described in detail elsewhere.