Research
Mixed
Roux-en-Y gastric bypass (RYGB) surgery induces a profound shift in gut microbiota, specifically a 52-fold increase in Proteobacteria (notably Enterobacter hormaechei) and a decrease in Firmicutes, which correlates with weight loss and metabolic enhancement.
Roux-en-Y gastric bypass surgery significantly alters gut bacteria, increasing Proteobacteria and decreasing Firmicutes. This microbial shift is linked to improved metabolism and weight loss, suggesting that surgery's benefits extend beyond simple calorie restriction.
ModerateSupportsMEDIUM confidence
We show substantial shifts of the main gut phyla towards higher levels of Proteobacteria (52-fold) specifically Enterobacter hormaechei. We also find low levels of Firmicutes (4.5-fold) and Bacteroidetes (2-fold) in comparison to sham-operated rats.
Why this rating
Study is conducted on a non-obese rat model, not humans, limiting direct clinical applicability to morbid obesity.
Source
Metabolic surgery profoundly influences gut microbial–host metabolic cross-talk
Jia V. Li et al. · Gut · 2011
DOI 10.1136/gut.2010.234708
mechanism_only · n=29Cited 446×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
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Related findings · Mixed
- Bariatric surgery (VSG and RYGB) is the most effective and sustainable treatment for obesity, producing marked and sustained weight loss that non-surgical interventions cannot match.Strong
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