Cross-category comparison
Wegovy vs Gastric Bypass
Different categories, normalised only where comparison is meaningful.
Wegovy injection
STEP 1: mean -14.9% at 68 weeks with 2.4 mg; 7.2 mg is now a licensed maintenance option for adults with obesity if needed
Roux-en-Y gastric bypass
Long-term evidence is extensive; ASMBS reports strong durable weight loss and 2024 long-term data show substantial maintenance out to 10–20 years
How to use this comparison
Compare the factual differences below. We do not assign numerical treatment rankings: outcomes depend on the specific treatment, population, follow-up and your clinical circumstances.
Category-specific detail
| Issue | Wegovy injection | Roux-en-Y gastric bypass |
|---|---|---|
| Anatomical change | Not covered in this row | Small stomach pouch connected to a lower segment of small intestine, bypassing part of the stomach and small bowel |
| Diabetes / metabolic | Not covered in this row | Very strong metabolic/diabetes evidence |
| Evidence anchor | STEP 1: mean -14.9% at 68 weeks with 2.4 mg; 7.2 mg is now a licensed maintenance option for adults with obesity if needed | Not covered in this row |
| How it works | GLP-1 receptor agonist | Not covered in this row |
| How taken | Weekly injection — Once weekly | Not covered in this row |
| Main trade-offs | Injection; GI effects; The new 7.2 mg option should not be compared using old 2.4 mg-only trial assumptions; NHS access remains pathway-limited | Not covered in this row |
| Maintenance | Long-term support/treatment matters; weight regain after stopping has been demonstrated | Not covered in this row |
| NHS context | NICE-recommended in specialist weight-management pathways; access depends on pathway | Established NHS bariatric procedure |
| Nutrition burden | Not covered in this row | Higher long-term micronutrient burden than sleeve; lifelong supplements and blood monitoring are important |
| Procedure type | Not covered in this row | Laparoscopic surgery |
| Reflux | Not covered in this row | Often considered favourable where significant reflux is a major issue |
| Reversible | Not covered in this row | Technically revisable but not treated as a simply reversible procedure |
| Revision | Not covered in this row | Revision is possible but complex and specialist |
| UK licence | UK weight management licence | Not covered in this row |
A detail omitted from one column is not evidence that it is irrelevant to that treatment. Use the full guides and discuss clinical suitability with your treating team.
Want support putting this into practice?
The Shift Programme is being built to combine evidence-led education, decision support, practical tools, progress tracking and long-term maintenance.
Sources & evidence
Check the underlying guidance directly: