Research

Mixed

Dietary modulation of the gut microbiota, specifically through the intake of prebiotics, probiotics, and polyphenols, can alter microbial composition and metabolic activity to confer health benefits, although human clinical efficacy remains ambiguous compared to animal models.

Focus on diverse plant-based foods (prebiotics) and fermented foods (polyphenols/probiotics) rather than relying on specific supplement brands. Human evidence for specific probiotic strains is mixed, so consistency in dietary fiber intake is likely more impactful than isolated supplements.

ModerateQualifiesMEDIUM confidence
A number of dietary strategies are available for modulating either the composition or metabolic/immunological activity of the human gut microbiota: probiotics, prebiotics and polyphenols are among the most well established... However, there is also a persistent lack of understanding as to the very nature of probiotics... the data in humans remain ambiguous.
Julian R. Marchesi et al. · Gut · 2015

Why this rating

The paper is a review highlighting strong animal data but equivocal/ambiguous human clinical trials.

Source

The gut microbiota and host health: a new clinical frontier

Julian R. Marchesi et al. · Gut · 2015

DOI 10.1136/gutjnl-2015-309990

narrative_reviewCited 2,301×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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