Last updated August 22, 2026
Key finding
Femoral neck aBMD decreased significantly more after RYGB than after SG (mean difference -2.8% [-4.7 to -0.8]).
This study compared Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) regarding their effects on bone health in patients with type 2 diabetes, finding significant differences in bone mineral density and biochemical markers.
Quick read
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EvidenceScore™
Moderate
Study type
RCTs
Follow-up
Long-Term (1–5 y)
Risk of bias
Some Concerns
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Plain-language summary
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Study focus
This study compared Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) regarding their effects on bone health in patients with type 2 diabetes, finding significant differences in bone mineral density and biochemical markers.
Understanding the impact of different bariatric surgeries on bone health is crucial for managing long-term outcomes in patients with type 2 diabetes. The findings suggest that RYGB may pose a higher risk for bone density loss, which could lead to increased fracture risk, highlighting the need for monitoring and potential interventions in this population.
Limited sample size may affect generalizability. Short follow-up period may not capture long-term effects. Potential confounding factors not fully controlled.
Published in
Publication details and source links for this paper.
Dag H, Thor OWH, Erling H, et al. Roux-en-Y Gastric Bypass vs Sleeve Gastrectomy: Effects on Bone Health in Patients with Type 2 Diabetes. The Journal of Clinical Endocrinology and Metabolism. 2021;106(2):501-511. doi:10.1210/clinem/dgaa808
Femoral neck aBMD decreased significantly more after RYGB than after SG (mean difference -2.8%, p < 0.001).
Total hip aBMD decreased significantly more after RYGB than after SG (mean difference -3.0%, p < 0.001).
Lumbar spine aBMD decreased significantly more after RYGB than after SG (mean difference -4.2%, p < 0.001).
Evidence network
Understand where this research contributes within the broader evidence network.
This study contributes evidence to Gastric bypass, Sleeve gastrectomy and Bone mineral density (BMD), Change in Areal Bone Mineral Density at Lumbar Spine, Change in Areal Bone Mineral Density at Total Hip, and 2 more.
This study contributes evidence to
Primary intervention
Gastric bypass
Primary outcomes
Evidence topics
Primary intervention
Intervention and outcome relationships this study adds to the evidence network.
Editorial context
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Evidence network role
This section describes how the study fits into the current evidence network. It does not determine whether an intervention works on its own.
1
Related topics
10
Evidence pairs
12
Related studies
Evidence topic
Contributes evidence
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Primary evidence
Evidence relationship
Related evidence
Evidence topic
Save evidence
Intervention
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Core evidence
The primary outcomes reported in this study.
Gastric bypass → Bone mineral density (BMD)
Gastric bypass → Bone mineral density (BMD)
Gastric bypass → Change in Areal Bone Mineral Density at Lumbar Spine
Gastric bypass → Change in Areal Bone Mineral Density at Lumbar Spine
Gastric bypass → Change in Areal Bone Mineral Density at Total Hip
Gastric bypass → Change in Areal Bone Mineral Density at Total Hip
Sleeve gastrectomy → Bone mineral density (BMD)
Sleeve gastrectomy → Bone mineral density (BMD)
Sleeve gastrectomy → Change in Areal Bone Mineral Density at Lumbar Spine
Sleeve gastrectomy → Change in Areal Bone Mineral Density at Lumbar Spine
Sleeve gastrectomy → Change in Areal Bone Mineral Density at Total Hip
Sleeve gastrectomy → Change in Areal Bone Mineral Density at Total Hip
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Relationships organized using the Dediabetes Evidence Intelligence™ framework.
This study contributes to evidence on Bariatric Procedures and Change in Areal Bone Mineral Density at Lumbar Spine, Bariatric Procedures and Change in Areal Bone Mineral Density at Total Hip.
This study contributes to the evidence on the following intervention-outcome relationships.
Curated evidence collections and hubs this study is part of.
All studies on Bariatric Procedures
Contributes to Bariatric Procedures evidence base.
All studies measuring Change in Areal Bone Mineral Density at Lumbar Spine
Measures Change in Areal Bone Mineral Density at Lumbar Spine as a key outcome.
All studies measuring Change in Areal Bone Mineral Density at Total Hip
Measures Change in Areal Bone Mineral Density at Total Hip as a key outcome.
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1 results
1 results
1 results
1 results
1 results
Generated from the study's connected evidence using Evidence Intelligence™.
Bariatric Procedures may worsen Bone Mineral Density or be associated with harm.
ConsistencyScore™: Consistency cannot yet be determined from the available evidence.
Ranked evidence signals
Bone mineral density (BMD)
EvidenceScore™ Emerging | EvidenceScore™ 59.0 | moderate negative | ConsistencyScore™ Unclear | 1 study
Why this answer: This answer is based on a single supporting study.
Limitations
Gastric bypass appears to improve Serum P1NP.
ConsistencyScore™: Consistency cannot yet be determined from the available evidence.
Ranked evidence signals
Serum P1NP
EvidenceScore™ Emerging | EvidenceScore™ 59.0 | strong positive | ConsistencyScore™ Unclear | 1 study
Why this answer: This answer is based on a single supporting study.
Limitations
Gastric bypass appears to improve Type IV collagen.
ConsistencyScore™: Consistency cannot yet be determined from the available evidence.
Ranked evidence signals
Type IV collagen
EvidenceScore™ Emerging | EvidenceScore™ 59.0 | strong positive | ConsistencyScore™ Unclear | 1 study
Why this answer: This answer is based on a single supporting study.
Limitations
Sleeve gastrectomy appears to improve Serum P1NP.
ConsistencyScore™: Consistency cannot yet be determined from the available evidence.
Ranked evidence signals
Serum P1NP
EvidenceScore™ Emerging | EvidenceScore™ 59.0 | strong positive | ConsistencyScore™ Unclear | 1 study
Why this answer: This answer is based on a single supporting study.
Limitations
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