Mixed
Roux-en-Y gastric bypass (RYGB) surgery induces rapid, persistent, and distinct alterations in gut microbiota composition and function, including increased diversity and specific taxonomic shifts, which occur largely within the first 3 months and are maintained for at least one year.
If you undergo RYGB surgery, expect your gut bacteria to change significantly within the first 3 months. These changes include increased diversity and shifts in specific bacteria (like increased E. coli and decreased F. prausnitzii). These changes are linked to metabolic improvements and are maintained for at least a year. You must take prescribed supplements (B12, Calcium, etc.) as your anatomy has changed, affecting nutrient absorption. Dietary choices should support this new microbial environment, potentially favoring foods that support the observed shifts (e.g., proteins, fibers that support transport systems).
In parallel with the weight loss and metabolic improvements, gut microbial diversity increased within the first 3 months after RYGB and remained high 1 year later. RYGB led to altered relative abundances of 31 species... within the first 3 months... Sixteen of these species maintained their altered relative abundances during the following 9 months.
Why this rating
Longitudinal study with small sample size (n=13) and lenient statistical thresholds (q < 0.15-0.22) to detect low-abundance changes.
Source
Roux-en-Y gastric bypass surgery of morbidly obese patients induces swift and persistent changes of the individual gut microbiota
Albert Pallejá et al. · Genome Medicine · 2016
DOI 10.1186/s13073-016-0312-1
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
- Severely protein-deficient diets (2–3% energy) induce lean body mass loss and metabolic imbalance, whereas adequate protein intake (0.66 g/kg/d minimum) is a prerequisite for maintaining muscle, bone, and physiological function.Strong
- For patients with Class III obesity (BMI >39.9 kg/m2), metabolic bariatric surgery (MBS) is significantly more effective than any currently approved medication, with BilioPancreatic Diversion (BPD) showing the highest estimated weight loss.Strong
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