As the national body for bariatric and metabolic surgeons in India, OSSI is committed to advancing standards of care. These revised guidelines supersede the 2023 edition and align with the 2022 ASMBS/IFSO Guidelines and IFSO-APC Consensus Statements. They acknowledge the unique South Asian phenotype, where obesity-related complications occur at lower BMI levels than in Western populations.
Obesity is a chronic, progressive, relapsing disease.
Bariatric and metabolic surgery (MBS) is an effective treatment for obesity and related diseases.
MBS is a life-altering, potentially life-saving intervention, not cosmetic surgery.
Indian patients require lower BMI thresholds for intervention due to higher metabolic risk.
Current MBS procedures act through restriction, malabsorption and metabolic modulation.
Metabolic surgery improves diabetes independent of weight loss.
Anti-obesity medications (AOMs) complement but do not replace MBS in appropriate candidates.
OSSI adopts the 2022 ASMBS/IFSO criteria adapted for Asians as per IFSO-APC recommendations. In Asian individuals, BMI ≥25 kg/m² represents clinical obesity, with lower surgical thresholds reflecting increased metabolic risk.
| BMI Threshold | Indication | Comorbidity Requirement |
|---|---|---|
| ≥ 27.5 kg/m² | MBS may be recommended | Life-threatening disorders like T2DM, OSA or cardiomyopathy |
| ≥ 30 kg/m² | MBS may be recommended | T2DM or metabolic syndrome inadequately controlled |
| ≥ 32.5 kg/m² | MBS recommended | Presence of at least one significant obesity-related comorbidity |
| ≥ 35 kg/m² | MBS highly recommended | With or without obesity-related comorbidities |
| ≥ 37.5 kg/m² | MBS strongly recommended | Comorbidities not required for consideration |
Active alcohol or substance use disorder (psychiatric clearance required).
Uncontrolled psychiatric illness impairing consent or compliance.
Pregnancy and breastfeeding.
Inability to adhere to nutritional supplementation or follow-up.
Malignancy with life expectancy <5 years, unless indicated for palliation or quality of life.
The following minimal access procedures are endorsed by OSSI, ASMBS, IFSO, and IFSO-APC:
Sleeve Gastrectomy (VSG)
Roux-en-Y Gastric Bypass (RYGB)
One Anastomosis Gastric Bypass (OAGB)
Biliopancreatic Diversion with Duodenal Switch (BPD-DS)
Single Anastomosis Duodeno Ileal Bypass (SADI)
Procedures published by Indian authors in peer-reviewed journals may be considered non-standard procedures, but can be performed under accepted procedures.
Unpublished procedures remain experimental and should be performed only within approved clinical trials registered with CTRI or ClinicalTrials.gov.
EBTs such as ESG, ESR, and IGB may be considered:
For patients below surgical BMI criteria.
As a bridge to surgery in super-obese patients.
For patients unfit for or unwilling to undergo surgery.
EBT procedures should be performed by appropriately credentialed endoscopist / surgeon.
Refer to OSSI guidelines on Bariatric and Metabolic Surgery for detailed guidance.
AOMs are prescribed in line with the 2024 IFSO and 2026 OSSI-ESI consensus:
GLP-1 receptor agonists and newer incretin therapies may be used pre-operatively to reduce risk and improve metabolic control.
AOMs can be used after MBS for inadequate weight loss or weight regain.
AOMs are not a substitute for MBS in eligible surgical candidates.
Combined AOM-MBS therapy may be considered on an individual MDT basis.
Refer to the OSSI Position Statement on Anti-Obesity Medications for detailed guidance.
These guidelines represent the current consensus of the OSSI Executive Committee and provide a framework for clinical decision-making. They do not replace individualized clinical judgment and will be updated as new evidence emerges.
