Research

Mixed

Bariatric surgery (RYGB, SG, BPD/DS) is the most effective long-term treatment for severe obesity, achieving 15-30% total weight loss, but carries significant risks of micronutrient deficiencies and lean body mass loss due to anatomical malabsorption.

Bariatric surgery is the most effective long-term weight loss option for severe obesity, but it is not a simple fix. It requires lifelong commitment to high-dose nutritional supplementation and regular medical monitoring to prevent serious deficiencies in iron, B12, and calcium, as well as loss of muscle mass. The procedure works through complex metabolic changes, not just stomach size reduction.

GoodQualifiesHIGH confidence
Currently, the most effective long-term weight loss treatment for severe obesity is bariatric surgery (BS), which is associated with a total weight loss of 15–30%, mostly sustained over time... Risk factors for poor nutritional status and excessive loss of lean body mass and bone include reduced dietary quality and inadequate intake, altered nutrient absorption, and poor patient compliance with nutrient supplementation.
Violeta Moizé et al. · Annual Review of Nutrition · 2024

Why this rating

Based on a comprehensive review of multiple studies and large patient networks, though individual variability exists.

Source

Nutritional Challenges and Treatment After Bariatric Surgery

Violeta Moizé et al. · Annual Review of Nutrition · 2024

DOI 10.1146/annurev-nutr-061121-101547

narrative_reviewCited 17×
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DOI resolved against Crossref · corpus check 2026-06-10

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