Research

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A high pre-treatment Prevotella-to-Bacteroides (P/B) ratio predicts significantly greater body weight and fat loss on energy-restricted diets, specifically when dietary fiber intake is high.

If you are struggling with weight loss on a standard calorie-restricted diet, your gut bacteria might be the missing variable. Specifically, if you have a high Prevotella-to-Bacteroides ratio, increasing your dietary fiber intake can significantly amplify your weight loss results. This suggests that personalized nutrition, based on gut microbiome testing, could be more effective than generic 'one-size-fits-all' diet advice.

GoodQualifiesHIGH confidence
Individuals with high P/B lost more body weight and body fat compared to individuals with low P/B, confirming that individuals with a high P/B are more susceptible to weight loss on a diet rich in fiber.
Mads F. Hjorth et al. · International Journal of Obesity · 2018

Why this rating

Randomized controlled trial design with post-hoc stratification; robust statistical adjustment for covariates.

Source

Prevotella-to-Bacteroides ratio predicts body weight and fat loss success on 24-week diets varying in macronutrient composition and dietary fiber: results from a post-hoc analysis

Mads F. Hjorth et al. · International Journal of Obesity · 2018

DOI 10.1038/s41366-018-0093-2

rct · n=80Cited 268×
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DOI resolved against Crossref · corpus check 2026-06-10

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