Research
Mixed
A low-fat vegan diet increases the relative abundance of Faecalibacterium prausnitzii and preserves Bacteroides fragilis levels compared to a control diet, and these microbial shifts correlate with greater weight loss and improved insulin sensitivity.
Eating a low-fat vegan diet changes your gut bacteria in ways that support weight loss. Specifically, it increases Faecalibacterium prausnitzii and helps maintain Bacteroides fragilis, both of which are linked to better insulin sensitivity and fat loss.
GoodSupportsHIGH confidence
The relative abundance of Faecalibacterium prausnitzii increased in the vegan group (+5.1% [95% CI, +2.4 to +7.9%]; p < 0.001) and correlated negatively with changes in weight (r = −0.24; p = 0.01)... The relative abundance of Bacteroides fragilis decreased in both groups, but less in the vegan group, making the treatment effect positive (+18.9% [95% CI, +14.2 to +23.7%]; p < 0.001)... a smaller reduction in Bacteroides fragilis was associated with a greater loss of body weight... and a greater increase in insulin sensitivity.
Why this rating
Randomized clinical trial with microbiome sequencing.
Source
Effects of a Low-Fat Vegan Diet on Gut Microbiota in Overweight Individuals and Relationships with Body Weight, Body Composition, and Insulin Sensitivity. A Randomized Clinical Trial
Hana Kahleová et al. · Nutrients · 2020
DOI 10.3390/nu12102917
rct · n=168Cited 116×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
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
This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →