Mostly true True only under certain conditions Certainty of evidence: moderate provisional C-BAR-06

Bariatric surgery causes measurable hip and spine bone loss (and fracture risk).

In short: This claim is mostly correct for gastric bypass-type operations, which reduce bone density and raise fracture risk by roughly 25-70%; after sleeve gastrectomy hip bone density falls modestly, but large studies have not shown more fractures.

Conclusion: Mostly correct for gastric bypass-type operations; after sleeve, hip bone density falls modestly but large studies have not shown more fractures.

Original statement
Scientific assessment
Scientific evidence in detail
In plain language
Studies on this claim
Regional context
What applies in my country?
References

Original statement

يُضاف إلى ذلك خسارة عظمية مؤكدة

verbatim according to source. Translation by the project; the Arabic wording is authoritative.

Translation

Bariatric surgery causes measurable hip and spine bone loss (and fracture risk).

Origin

Source status: Archive editors
Attribution: Archive editors (eltayebat.com); not necessarily Elawady's own words
Origin: https://eltayebat.com/rule/bariatric-surgery/
Attribution uncertainty: Editorial summary/narrative and study selection written by the archive operators; the archive states that the cited research documents harm independently of Dr. Diaa's words.

Claimed mechanism: Weight loss, malabsorption, hormonal change.
Claimed health effect: Bone loss, fractures.
Population concerned: Bariatric patients
Geographic restriction by Elawady: not applicable

Scientific assessment

Mostly true – Correct at its core, but with limitations or minor inaccuracies.

Certainty of evidence: moderate – Further research may still affect the assessment.

1. What was claimed?

Hip and spine bone loss.

2. What is demonstrably correct?

Spine bone loss in the first year after RYGB (about -3.3%) is confirmed by two methods (A-BAR-18); lower hip BMD and poorer microarchitecture 10+ years after RYGB vs BMI-matched controls (A-BAR-19); fracture risk increased: RR 1.38 (I-BAR-07), HR 1.26-1.32 after bypass (I-BAR-08); more fractures in ARMMS-T2D (I-BAR-02).

3. What is wrong or exaggerated?

Hip loss on DXA in the first year was not confirmed by QCT (A-BAR-18); the archive-cited UK study found no significant fracture increase at 2.2 years (A-BAR-17); procedure-specific (banding no effect; sleeve inconclusive in I-BAR-07).

4. What remains unclear?

Sleeve-specific long-term fracture risk. Current data: no increase in major osteoporotic fractures after sleeve in a French national cohort (I-BAR-123) and after restrictive procedures in a meta-analysis (I-BAR-124); hip BMD falls after sleeve (I-BAR-125); less bone loss after sleeve than bypass in an RCT (I-BAR-126).

5. Which studies support it?

A-BAR-18, A-BAR-19, I-BAR-07, I-BAR-08.

6. Which studies contradict it?

A-BAR-17; for sleeve: I-BAR-123, I-BAR-124, I-BAR-126.

7. What applies to Germany and Europe?

Most key data are European (Sweden SOS/SOReg, Finland SLEEVEPASS, Switzerland SM-BOSS). European and international society guidelines consider bariatric surgery for severe obesity with lifelong follow-up.

8. What is known about Egypt?

No Egypt-specific outcome data were identified in this review. Elawady states in a transcript that sleeve gastrectomy is very widely performed in Egypt ('مصر كلها بتعملها'); the procedure-specific risks (reflux, deficiencies) apply wherever it is performed, and follow-up quality (supplements, endoscopy, mental-health screening) determines part of the risk.

9. What practical conclusion is appropriate?

Bone health monitoring is part of bariatric aftercare, especially after bypass.

Assessment details

Rationale for certainty of evidence: Consistent for RYGB/BPD; uncertain for sleeve; DXA measurement artifacts complicate hip data.
Source quality: Cohorts and imaging studies.
Regional transferability: European registries included.
Individual exceptions: Evidence strongest for bypass and biliopancreatic diversion; banding shows little effect.
Regional scope of the claim: general (biological/medical)
Last reviewed: 26 October 2026 provisional

Scientific evidence in detail

True only under certain conditions – The claim holds only for certain doses, groups of people, preparations or circumstances.

Research question: Does bariatric surgery (including sleeve) cause measurable hip and spine bone loss and increased fracture risk?

Research question in detail (PICO)

Population

Adults after bariatric surgery

Intervention or exposure

RYGB, sleeve, banding

Comparison

Obese non-operated controls; between procedures

Geographic scope

universal biology

Outcomes

BMD hip/spine
Fracture incidence

Study results as reported by the authors. Our assessment follows below.

What speaks for the claim?

Fractures after weight-loss surgery in Quebec

Rousseau C et al.. BMJ 2016 · PMID 27814663 · DOI 10.1136/bmj.i3794 Case-control studyfull text, structured risk-of-bias assessment

Nested case-control: fractures increased after bariatric surgery vs obese controls.

Actual result
Adjusted RR 1.38 (1.23-1.55).
Methodological quality
moderate
Relevance
direct (mostly bypass)
Limitations
Observational

Original publication
Meta-analysis: bone density after sleeve

Jaruvongvanich et al.. Surg Obes Relat Dis 2019 · PMID 31311755 · DOI 10.1016/j.soard.2019.06.006 Meta-analysisabstract checkednewly added

Sleeve-specific meta-analysis: hip and femoral-neck BMD fall after sleeve.

Actual result
Total hip -0.06 g/cm2 (-0.09 to -0.03); spine NS.
Methodological quality
moderate
Relevance
direct for sleeve BMD
Limitations
DXA artefact, no controls

Original publication

What speaks against the claim?

French study: broken bones after obesity surgery

Paccou et al.. J Bone Miner Res 2020 · PMID 32187759 · DOI 10.1002/jbmr.4012 Cohort studyabstract checkednewly added

French national cohort: major osteoporotic fractures increased after bypass but not after sleeve.

Actual result
Bypass HR 1.70 (1.46-1.98); sleeve not increased.
Methodological quality
moderate
Relevance
direct, sleeve-specific
Limitations
Age 40-65 only

Original publication
Meta-analysis: fractures by type of operation

Saad et al.. Osteoporos Int 2022 · PMID 34988627 · DOI 10.1007/s00198-021-06206-9 Meta-analysisabstract checkednewly added

Meta-analysis: fracture risk increased after malabsorptive but not restrictive procedures.

Actual result
+45% malabsorptive; restrictive not increased.
Methodological quality
moderate
Relevance
direct
Limitations
Heterogeneity

Original publication

What does the overall evidence say?

Editorial assessment based on the studies above – not itself a study result.

Which position is better supported?

Bone loss and higher fracture risk are well documented after gastric bypass-type operations; after sleeve, hip BMD falls modestly but fracture risk has not been shown to increase.

Why some studies weigh more

Procedure-specific cohorts and an RCT (Oseberg) carry most weight.

Is a causal relationship established? Probable For bypass: consistent, with plausible mechanisms (calcium/vitamin D malabsorption, unloading).

Remaining uncertainty

Long-term sleeve fracture risk in older patients.

Justified conclusion

Mostly correct for bariatric surgery as a whole, conditional on procedure.

Why do studies seem to disagree?

Hip DXA loss vs no QCT change (A-BAR-18) reflects DXA artefacts with fat loss. Sleeve BMD loss without fracture increase may reflect smaller effect or insufficient follow-up.

Does this depend on the country?

General biological effects: Universal.
Eating habits: Calcium/vitamin D intake affects risk.
Origin of the food: Not applicable (surgical procedure, not a food).
Contaminants: Not applicable (surgical procedure, not a food).
National production conditions: Not studied.
Legal rules: Not applicable.
Actual monitoring data: No Egyptian national bariatric registry data were found; one Egyptian single-surgeon series (I-BAR-105) and one Egyptian RCT (I-BAR-136) were identified.

A regional difference that changes the conclusion is not supported by robust data.

Statistical re-check

CI symmetry and absolute rate difference – HRs log-symmetric; 0.37 extra major osteoporotic fractures per 1000 patient-years overall. recalculated

Certainty of the overall evidence (GRADE, simplified)

Main outcome

Fracture risk after bariatric surgery (procedure-specific)

Starting level

low (observational studies)

Reasons for downgrading

inconsistency between procedures

Reasons for upgrading

dose-response by malabsorptive component

Result

moderate

Simplified assessment by a single reviewer, following the GRADE approach; not a formal GRADE panel. GRADE rates the body of evidence for one outcome, not individual studies.

Clinical guidelines and official statements checked

AACE/TOS/ASMBS/OMA/ASA: Clinical Practice Guidelines for Perioperative Nutrition, Metabolic and Nonsurgical Support (I-BAR-09) (2019) · Original publication
Executive summary: bariatric procedures remain a safe and effective intervention for higher-risk patients with obesity; a team approach to perioperative care is mandatory, with special attention to nutritional and metabolic issues (abstract).

Search strategy

Documented literature searches for this review (search strings in the original database syntax).

Database	Date	Search	Looking for	Hits	Included
Europe PMC	26 October 2026	`(TITLE:"fracture*" OR TITLE:"bone mineral density" OR TITLE:"bone loss") AND (TITLE:"sleeve gastrectomy" OR TITLE:"bariatric") AND (PUB_TYPE:"Meta-Analysis" OR TITLE:"meta-analysis" OR TITLE:"nationwide" OR TITLE:"population-based") AND PUB_YEAR:[2019 TO 2026]`	both directions	11
PubMed	26 October 2026	`(Oseberg OR Hofso D[au]) AND gastric bypass AND sleeve gastrectomy AND diabetes remission AND randomised`	both directions	12

Open questions

Sleeve fracture risk beyond 10 years.

How deeply was this checked?

10 linked studies: 1 checked in full text (1 of them with a structured risk-of-bias assessment), 9 on the basis of the abstract, 0 bibliographically only. No formal assessment with two independent reviewers and no independent human expert review has taken place yet.

Last scientific review: 26 October 2026

History of the verdict

25 October 2026 · Phase 1 · Initial assessment: Mostly true (moderate)
26 October 2026 · Phase 4 (systematic evidence review) · Re-examined with extended evidence; verdict unchanged: Mostly true (moderate)
Unchanged. New sleeve-specific data make the procedure dependence explicit; bottom line sharpened.
New sources: I-BAR-125 I-BAR-123 I-BAR-124 I-BAR-126

In plain language

The archive says weight-loss surgery causes bone loss. This is largely correct for gastric bypass and similar operations: bone density falls and fractures become more frequent (about 25-40% more in large studies). For banding there was little effect, and for sleeve gastrectomy the evidence is still unclear. One study cited by the archive itself found no increase in fractures in the first two years.

Studies on this claim

Studies supporting the claim (5)

Bone after gastric bypass: depends on the scanner

Yu EW et al.. J Bone Miner Res 2014 · PMID 23929784 · DOI 10.1002/jbmr.2063

Cohort studycited by the Tayebat archiveabstract checked

Spine bone density fell about 3% in one year; hip loss seen on DXA was not confirmed by CT.

Bariatric surgery causes measurable hip and spine bone loss (and fracture risk).

Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim

Original publication · Scientific details

Study explained simply
What did the researchers want to find out?
Bone loss
How was the study done?
Prospective controlled
How many people, animals or samples were studied?
50
What was actually found?
Spine loss; hip uncertain
How large was the observed effect?
-3.3% spine
What do the results mean in everyday life?
Some bone loss is real
What are the study's limitations?
Small
What does it say about Elawady's specific claim?
Partly supports
Do the results apply to Germany and Europe?
Applicable
What can explicitly not be concluded from this study?
Fracture risk
Scientific details →
Bones 10 years after bypass

Lindeman KG et al.. J Bone Miner Res 2020 · PMID 32663365 · DOI 10.1002/jbmr.4112

Cross-sectional studycited by the Tayebat archiveabstract checked

Bypass patients had weaker bone structure than people of the same weight; band patients did not.

Bariatric surgery causes measurable hip and spine bone loss (and fracture risk).

Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim

Original publication · Scientific details

Study explained simply
What did the researchers want to find out?
Long-term bone
How was the study done?
Cross-sectional
How many people, animals or samples were studied?
100
What was actually found?
RYGB deficits
How large was the observed effect?
see results
What do the results mean in everyday life?
Bypass may harm bone long-term
What are the study's limitations?
Small
What does it say about Elawady's specific claim?
Partly supports
Do the results apply to Germany and Europe?
Applicable
What can explicitly not be concluded from this study?
Sleeve effect
Scientific details →
Fractures after weight-loss surgery in Quebec

Rousseau C et al.. BMJ 2016 · PMID 27814663 · DOI 10.1136/bmj.i3794

Case-control studyindependent cross-checkfull text, structured risk-of-bias assessment★ key study

Fractures were about 38% more frequent than in obese controls, clearly so only after biliopancreatic diversion.

Bariatric surgery causes measurable hip and spine bone loss (and fracture risk).

Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim

Original publication · Scientific details

Study explained simply
What did the researchers want to find out?
Fracture
How was the study done?
Nested case-control
How many people, animals or samples were studied?
177,464
What was actually found?
Higher risk
How large was the observed effect?
RR 1.38
What do the results mean in everyday life?
Bone health needs follow-up
What are the study's limitations?
Administrative data; controls not BMI-matched; short follow-up for sleeve; few bypass patients
What does it say about Elawady's specific claim?
Partly supports
Do the results apply to Germany and Europe?
Applicable
What can explicitly not be concluded from this study?
Sleeve-specific risk
Scientific details →
Swedish study: fractures after gastric bypass

Axelsson KF et al.. J Bone Miner Res 2018 · PMID 30011091 · DOI 10.1002/jbmr.3553

Cohort studyindependent cross-checkabstract checked

Fracture risk was about 26-32% higher than in similar people without surgery.

Bariatric surgery causes measurable hip and spine bone loss (and fracture risk).

Does the study support the specific claim? Yes · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim

Original publication · Scientific details

Study explained simply
What did the researchers want to find out?
Fracture
How was the study done?
Matched cohort
How many people, animals or samples were studied?
~78,000
What was actually found?
Higher risk
How large was the observed effect?
HR 1.26-1.32
What do the results mean in everyday life?
Bone protection is important after bypass
What are the study's limitations?
Short follow-up
What does it say about Elawady's specific claim?
Supports (bypass)
Do the results apply to Germany and Europe?
European
What can explicitly not be concluded from this study?
Sleeve risk
Scientific details →
Meta-analysis: bone density after sleeve

Jaruvongvanich et al.. Surg Obes Relat Dis 2019 · PMID 31311755 · DOI 10.1016/j.soard.2019.06.006

Meta-analysisindependent cross-checkabstract checked

Bone density at the hip fell after sleeve, while the spine did not change significantly.

Hip and femoral neck BMD fall after sleeve; spine unchanged.

Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim

Original publication · Scientific details

Study explained simply
What did the researchers want to find out?
BMD after SG
How was the study done?
Meta-analysis
How many people, animals or samples were studied?
1,905
What was actually found?
Hip -0.06 g/cm2
How large was the observed effect?
MD -0.06
What do the results mean in everyday life?
Some bone loss at the hip
What are the study's limitations?
No controls; DXA artefact
What does it say about Elawady's specific claim?
Supports hip part
Do the results apply to Germany and Europe?
Applicable
What can explicitly not be concluded from this study?
Fracture risk
Scientific details →

Studies contradicting or limiting the claim (2)

UK: fractures after weight-loss surgery

Lalmohamed A et al.. BMJ 2012 · PMID 22867649 · DOI 10.1136/bmj.e5085

Cohort studycited by the Tayebat archiveabstract checked

No significant increase in fractures in the first 2-3 years.

Bariatric surgery causes measurable hip and spine bone loss (and fracture risk).

Does the study support the specific claim? No · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim

Original publication · Scientific details

Study explained simply
What did the researchers want to find out?
Fracture
How was the study done?
Matched cohort
How many people, animals or samples were studied?
12,521
What was actually found?
No increase
How large was the observed effect?
RR 0.89
What do the results mean in everyday life?
Short-term reassuring
What are the study's limitations?
Short follow-up
What does it say about Elawady's specific claim?
Limits claim
Do the results apply to Germany and Europe?
European
What can explicitly not be concluded from this study?
Long-term risk
Scientific details →
French study: broken bones after obesity surgery

Paccou et al.. J Bone Miner Res 2020 · PMID 32187759 · DOI 10.1002/jbmr.4012

Cohort studyindependent cross-checkabstract checked★ key study

Serious osteoporotic fractures increased after gastric bypass (about 70% more) but not after sleeve.

No increase in major osteoporotic fractures after sleeve; increase after bypass (HR 1.70).

Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim

Original publication · Scientific details

Study explained simply
What did the researchers want to find out?
Fracture risk by operation
How was the study done?
National cohort
How many people, animals or samples were studied?
81,984
What was actually found?
Bypass HR 1.70; sleeve not increased
How large was the observed effect?
HR 1.22 overall
What do the results mean in everyday life?
Bone risk depends on operation
What are the study's limitations?
Administrative data
What does it say about Elawady's specific claim?
Limits the claim for sleeve
Do the results apply to Germany and Europe?
Directly European
What can explicitly not be concluded from this study?
Very long-term risk
Scientific details →

Studies with mixed or unclear results (3)

Diabetes 12 years after randomized surgery vs medicine

Courcoulas AP et al.. JAMA 2024 · PMID 38411644 · DOI 10.1001/jama.2024.0318

Randomised controlled trialindependent cross-checkabstract checked★ key study

Blood sugar control stayed better after surgery; full remission was uncommon in both groups but more frequent after surgery (12.7% vs 0%).

Bariatric surgery causes measurable hip and spine bone loss (and fracture risk).

Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim

Original publication · Scientific details

Study explained simply
What did the researchers want to find out?
Long-term T2D
How was the study done?
Pooled RCT follow-up
How many people, animals or samples were studied?
262
What was actually found?
Surgery better; remission declines
How large was the observed effect?
HbA1c -1.1% at 12 y
What do the results mean in everyday life?
Relapse is common, but surgery keeps an advantage
What are the study's limitations?
Crossover, small
What does it say about Elawady's specific claim?
Partly supports erosion; contradicts 'no benefit'
Do the results apply to Germany and Europe?
Applicable
What can explicitly not be concluded from this study?
Mortality
Scientific details →
Meta-analysis: fractures by type of operation

Saad et al.. Osteoporos Int 2022 · PMID 34988627 · DOI 10.1007/s00198-021-06206-9

Meta-analysisindependent cross-checkabstract checked

Fractures were about 45% more frequent after bypass-type operations, but not after restrictive ones such as sleeve.

Fractures increased after malabsorptive procedures (+45%), not after restrictive ones.

Does the study support the specific claim? Partly · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim

Original publication · Scientific details

Study explained simply
What did the researchers want to find out?
Fracture risk by type
How was the study done?
Meta-analysis
How many people, animals or samples were studied?
19 studies
What was actually found?
Malabsorptive +45%; restrictive no increase
How large was the observed effect?
RR ~1.45
What do the results mean in everyday life?
Bone risk depends on operation
What are the study's limitations?
Heterogeneous
What does it say about Elawady's specific claim?
Partly supports claim
Do the results apply to Germany and Europe?
Applicable
What can explicitly not be concluded from this study?
Sleeve-only long-term
Scientific details →
Trial: bone after bypass vs sleeve

Hofsø et al.. J Clin Endocrinol Metab 2021 · PMID 33150385 · DOI 10.1210/clinem/dgaa808

Randomised controlled trialindependent cross-checkabstract checked

Hip and spine bone density fell more after bypass than after sleeve.

Bone loss greater after bypass than sleeve (randomised).

Does the study support the specific claim? Partly · Methodological quality: high · Certainty of evidence: see overall assessment of the claim

Original publication · Scientific details

Study explained simply
What did the researchers want to find out?
Bone effects RYGB vs SG
How was the study done?
RCT
How many people, animals or samples were studied?
92
What was actually found?
More bone loss after bypass
How large was the observed effect?
Spine -4.2% difference
What do the results mean in everyday life?
Bypass is harder on bone
What are the study's limitations?
Small, short
What does it say about Elawady's specific claim?
Refines the claim
Do the results apply to Germany and Europe?
Directly European
What can explicitly not be concluded from this study?
Fracture risk
Scientific details →

Regional context

Germany / EU

Egypt

What applies in my country?

General scientific assessment

Mostly true Mostly correct for gastric bypass-type operations; after sleeve, hip bone density falls modestly but large studies have not shown more fractures.

This statement concerns biological or medical relationships. The scientific assessment above applies regardless of the country; country-specific food data do not change it.

References

Bone loss after bariatric surgery: discordant results between DXA and QCT bone density.. Yu EW et al.. J Bone Miner Res 2014 · PMID 23929784 · DOI 10.1002/jbmr.2063
Bone Density and Trabecular Morphology at Least 10 Years After Gastric Bypass and Gastric Banding.. Lindeman KG et al.. J Bone Miner Res 2020 · PMID 32663365 · DOI 10.1002/jbmr.4112
Change in fracture risk and fracture pattern after bariatric surgery: nested case-control study.. Rousseau C et al.. BMJ 2016 · PMID 27814663 · DOI 10.1136/bmj.i3794
Fracture Risk After Gastric Bypass Surgery: A Retrospective Cohort Study.. Axelsson KF et al.. J Bone Miner Res 2018 · PMID 30011091 · DOI 10.1002/jbmr.3553
Changes in bone mineral density and bone metabolism after sleeve gastrectomy: a systematic review and meta-analysis.. Jaruvongvanich et al.. Surg Obes Relat Dis 2019 · PMID 31311755 · DOI 10.1016/j.soard.2019.06.006
Risk of fracture after bariatric surgery in the United Kingdom: population based, retrospective cohort study.. Lalmohamed A et al.. BMJ 2012 · PMID 22867649 · DOI 10.1136/bmj.e5085
Gastric Bypass But Not Sleeve Gastrectomy Increases Risk of Major Osteoporotic Fracture: French Population-Based Cohort Study.. Paccou et al.. J Bone Miner Res 2020 · PMID 32187759 · DOI 10.1002/jbmr.4012
Long-Term Outcomes of Medical Management vs Bariatric Surgery in Type 2 Diabetes.. Courcoulas AP et al.. JAMA 2024 · PMID 38411644 · DOI 10.1001/jama.2024.0318
Fracture risk following bariatric surgery: a systematic review and meta-analysis.. Saad et al.. Osteoporos Int 2022 · PMID 34988627 · DOI 10.1007/s00198-021-06206-9
Bone Mineral Density and Turnover After Sleeve Gastrectomy and Gastric Bypass: A Randomized Controlled Trial (Oseberg).. Hofsø et al.. J Clin Endocrinol Metab 2021 · PMID 33150385 · DOI 10.1210/clinem/dgaa808

← Back to overview

Bariatric surgery causes measurable hip and spine bone loss (and fracture risk).

Original statement

Translation

Origin

Scientific assessment

1. What was claimed?

2. What is demonstrably correct?

3. What is wrong or exaggerated?

4. What remains unclear?

5. Which studies support it?

6. Which studies contradict it?

7. What applies to Germany and Europe?

8. What is known about Egypt?

9. What practical conclusion is appropriate?

Assessment details

Scientific evidence in detail

What speaks for the claim?

Fractures after weight-loss surgery in Quebec

Meta-analysis: bone density after sleeve

What speaks against the claim?

French study: broken bones after obesity surgery

Meta-analysis: fractures by type of operation

What does the overall evidence say?

Which position is better supported?

Why some studies weigh more

Remaining uncertainty

Justified conclusion

Open questions

How deeply was this checked?

In plain language

Studies on this claim

Studies supporting the claim (5)

Bone after gastric bypass: depends on the scanner

Bones 10 years after bypass

Fractures after weight-loss surgery in Quebec

Swedish study: fractures after gastric bypass

Meta-analysis: bone density after sleeve

Studies contradicting or limiting the claim (2)

UK: fractures after weight-loss surgery

French study: broken bones after obesity surgery

Studies with mixed or unclear results (3)

Diabetes 12 years after randomized surgery vs medicine

Meta-analysis: fractures by type of operation

Trial: bone after bypass vs sleeve

Regional context

Germany / EU

Egypt

What applies in my country?

General scientific assessment

References