Bariatric Surgery Produces Greater Weight Loss and Changes Eating Habits

Dr. Neelam Pandey, Consultant Endocrinology, Pinnacle Superspecialty Centre, Gurgaon.

Bariatric surgery leads to greater weight loss than GLP-1 receptor agonists and appears to reduce food intake.

Bariatric surgery and obesity medicines are important treatment options for obesity, but they may affect weight and eating behavior in different ways. A review of eating behavior and a systematic review and meta-analysis comparing metabolic and bariatric surgery (MBS) with glucagon-like peptide-1 receptor agonists (GLP-1 RAs) provide insights into these differences.

Both Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) were linked to lower energy intake. This was mainly due to smaller meals and slower eating. However, studies did not show consistent changes in meal timing or the types of macronutrients people chose. Some studies found changes in food choices after surgery, but the findings were not consistent across all studies.

GLP-1-based therapies were also associated with lower energy intake and improvements in appetite-related behaviors. However, the review noted that objective evidence on how obesity medicines affect eating behavior remains more limited than the evidence available for bariatric surgery.

A separate systematic review and meta-analysis compared MBS with GLP-1 RA therapy and included 5 retrospective studies involving 5,944 participants. Of these, 3,489 underwent MBS and 2,455 received GLP-1 RA therapy. MBS was associated with greater total weight loss, with a mean difference of −18.15%, as well as a greater reduction in BMI, with a mean difference of 8.73 kg/m².

Overall, the available evidence suggests that bariatric surgery produces greater weight loss than GLP-1 RA therapy and reduces food intake through changes in satiety, meal size and eating rate. GLP-1-based medicines may produce some similar effects on appetite and food intake, but more objective research is needed to better understand how they influence eating behavior.

(Reference: Delgado LM, Barone G, Garcia G, Pilon G, Viana P, Marques FI, Bueno CB, Del Grande L, Theis C, Poli de Figueiredo S, Pompeu BF. Metabolic bariatric surgery versus GLP-1 receptor agonists for obesity management: A systematic review and meta-analysis. Obesity Surgery. 2026 Apr;36(4):1899-908, Contreras Hernández F, Villelabeitia I, Levine I, le Roux CW, Miras AD, Price RK. Effects of Bariatric Surgery and Obesity Medicines on Human Eating Behavior. Annual Review of Nutrition. 2026 May 15;46.);