Metabolic & Cardiometabolic
gastric bypass (RYGB) increases alcohol use disorder risk
In plain terms: Does gastric bypass increase alcohol use disorder risk?
Strong support Metabolic & Cardiometabolic 🔬 Includes disconfirming
Part of: 🩺 bariatric / metabolic surgery
RefutedContestedStrong support
consensus score 0.89
Yes—RYGB (more than sleeve) raises new-onset AUD risk, with altered ethanol pharmacokinetics, higher AUD prevalence, and elevated alcohol-related liver disease/mortality.
📅 Last reviewed: 2026-07-15 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: All trials, pooled (Meta-analysis)
MechanismIn-vitroAnimalObservationalRCTMeta-analysis
How the studies fall
17 support 0 contradict 1 tested null 1 mixed · 19 sources, 17 independent groups
The evidence (19)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Williams TJ et al 2026 · study_type: observational | observational | supports | low | Retrospective cohort, n=30 (20 sleeve gastrectomy, 10 RYGB) among patients seeking alcohol-problem treatment; mean AUDIT rose from 10.2 to 18.1 post-surgery (p<0.001), alcohol-dependence cases rose from 9 to 29 of 30. |
| Fakhoury 2025 · JAMA Netw Open | observational | tested-null | moderate | Confirms elevated post-bariatric AUD risk; incretin therapies may attenuate it—reinforces surgery-specific signal. |
| Sharpe E et al 2026 · study_type: observational | observational | supports | low | Qualitative study, semi-structured interviews with 11 UK women (post-bariatric, mostly RYGB) who developed problematic alcohol use without formal AUD diagnosis; identifies altered ethanol metabolism plus psychosocial drivers (identity chang |
| Scheen 2025 · Diabetes Metab | observational | supports | moderate | Review: bariatric surgery increases addiction/AUD risk (contrasting reduced risk with GLP-1 RAs). |
| Riedel 2024 · Int J Obes | observational | supports | moderate | Linked claims+survey data: elevated AUD rates after bariatric surgery confirmed in an independent German cohort. |
| Leggio L et al 2025 · study_type: observational | observational | supports | low | Non-systematic critical review of AUD-obesity crosstalk; states 'growing evidence of changes in alcohol drinking in people who undergo bariatric surgery for obesity' and reviews mechanisms (GLP-1, gut-brain axis) linking bariatric surgery t |
| King 2012 · JAMA | observational | supports | high | LABS-2 landmark: AUD prevalence rose from 7.6% (yr1) to 9.6% (yr2) post-op; increase concentrated after RYGB. |
| Sjoholm 2025 · Br J Surg | observational | supports | high | SOS up to 35yr: bariatric surgery associated with higher AUD incidence and increased alcohol-related mortality. |
| van Reekum EA et al 2025 · study_type: meta-analysis | meta-analysis | supports | moderate | Systematic review and meta-analysis, 79 studies (75 NRS, 4 RCTs), 732,149 MBS patients vs 7,670,770 non-surgical controls; MBS associated with 4/100 more substance use disorders (low certainty) beyond 2 years post-surgery, alongside slightl |
| Nazmin F et al 2025 · study_type: meta-analysis | observational | supports | low | Systematic review (PRISMA) of 12 studies (2013-2024) on nutritional status of bariatric patients with AUD; reports 'higher incidence of AUD after bariatric surgery, especially after sleeve gastrectomy or RYGB' with elevated alcohol sensitiv |
| Adeniran 2025 · Obesity (Silver Spring) | observational | supports | moderate | Multicenter RYGB cohort: RYGB linked to increased alcohol-related outcomes; independent confirmation of the RYGB signal. |
| Ibrahim 2025 · Clin Obes | observational | supports | high | PSM (15,808 pairs): post-bariatric AUD patients had higher alcohol-hepatitis (OR 1.67), cirrhosis (OR 1.49), mortality (OR 1.13). |
| Strømmen 2026 · Int J Obes | observational | mixed | moderate | Nationwide registry found gastric bypass carried higher alcohol use disorder rates than sleeve gastrectomy, supporting a procedure-specific (RYGB) risk. |
| Nazmin F et al 2025 · study_type: observational | observational | supports | low | Narrative review (PRISMA-guided search, 11 studies, 2013-present) on AUD incidence after bariatric surgery; found elevated risk especially after sleeve gastrectomy or RYGB, with increased alcohol sensitivity and earlier symptom onset. |
| Cheloff 2026 · Surg Obes Relat Dis | meta-analysis | supports | moderate | Systematic review and meta-analysis found meaningful rates of de novo alcohol use disorder and high-risk drinking after RYGB and sleeve gastrectomy. |
| Er 2026 · Surg Obes Relat Dis | observational | supports | moderate | Prospective cohort: alcohol use and drinking motives increase early after bariatric surgery. |
| Mahmud 2023 · JAMA Surg | observational | supports | high | Veterans Affairs cohort controlling for BMI and alcohol-use trajectory found RYGB associated with increased alcohol-related hospitalization and mortality. |
| Strømmen M et al 2026 · study_type: observational | observational | supports | moderate | Prospective non-randomized study, n=33 (RYGB=14, SG=19), no baseline AUD; oral/IV ethanol challenge pre-op and at 3/12/36 months. Both procedures roughly doubled ethanol Cmax and AUC and halved Tmax, more pronounced after RYGB, authors conc |
| Campuzano-Donoso M et al 2026 · study_type: observational | observational | supports | low | Narrative review synthesizing epidemiological, pharmacokinetic and neurobiological drivers of postoperative AUD/SUD; describes RYGB eliminating ethanol first-pass metabolism and accelerating absorption, creating a 'reward gap' that raises A |
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