Research

Mixed

Bariatric surgical procedures (Roux-en-Y gastric bypass, laparoscopic adjustable gastric banding, and biliopancreatic diversion/duodenal switch) provide substantial and durable weight loss (>45% excess weight loss) that persists for 10 to 20 years, significantly outperforming non-surgical medical therapy.

If you are considering bariatric surgery, understand that modern procedures like gastric bypass and banding are not short-term fixes. They provide substantial, durable weight loss (often 45-75% of excess weight) that lasts for 10-20 years. While reoperation rates exist, they have decreased with better techniques. Compared to lifestyle changes alone, which rarely maintain significant weight loss beyond a few years, surgery offers a significantly more effective long-term solution for obesity.

ModerateSupportsMEDIUM confidence
The meta-analysis of published long-term outcomes shows the principal bariatric surgical procedures provide substantial and durable weight loss... The results shown would appear to confirm the greater effectiveness and durability of bariatric surgery compared to optimal medical therapy.
Paul E. O’Brien et al. · Obesity Surgery · 2018

Why this rating

The study is a systematic review and meta-analysis of observational data and two RCTs, but the authors note 'low quality' of most studies due to lack of control data and high heterogeneity.

Source

Long-Term Outcomes After Bariatric Surgery: a Systematic Review and Meta-analysis of Weight Loss at 10 or More Years for All Bariatric Procedures and a Single-Centre Review of 20-Year Outcomes After Adjustable Gastric Banding

Paul E. O’Brien et al. · Obesity Surgery · 2018

DOI 10.1007/s11695-018-3525-0

Meta-analysis · 57 studiesCited 790×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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