Research

Energy balance

Weight loss interventions, regardless of macronutrient composition, consistently alter the ratio of Bacteroidetes to Firmicutes, often increasing microbial gene richness and improving metabolic parameters.

If you are overweight, losing weight will likely improve your gut microbiome diversity and metabolic health, regardless of whether you choose a high-fat or high-fiber diet to do it. The act of losing weight itself drives beneficial microbial shifts, such as an increase in Bacteroidetes and gene richness.

GoodSupportsHIGH confidence
Regardless of the macronutrient composition of the diet, individuals that lost a significant amount of body weight had a change in their ratio of Bacteroidetes to Firmicutes... Calorie restriction in obese and overweight individuals has also been shown to increase microbial gene richness, a parameter that was correlated to improved metabolic parameters.
Noah Voreades et al. · Frontiers in Microbiology · 2014

Why this rating

Supported by multiple studies (Ley et al., Faith et al., Cotillard et al.) showing consistent trends in B/F ratio and gene richness upon weight loss.

Source

Diet and the development of the human intestinal microbiome

Noah Voreades et al. · Frontiers in Microbiology · 2014

DOI 10.3389/fmicb.2014.00494

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DOI resolved against Crossref · corpus check 2026-06-10

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