Cheng · Carbohydrate polymers 2025 · Narrative review · n=?

The mutual effect of dietary fiber and polyphenol on gut microbiota: Implications for the metabolic and microbial modulation and associated health benefits.

Level 5 - mechanism / opinion, no new human data

Narrative review summarizing mechanistic interactions with no primary trial data or systematic review methodology reported

PubMed 40383597 · doi:10.1016/j.carbpol.2025.123541 · record verified 2026-08-26

What was done

The authors reviewed literature examining the synergistic interactions between dietary fiber and polyphenols, focusing on their joint impact on gut microbiota composition, short-chain fatty acid (SCFA) generation, gut barrier integrity, and metabolic regulation.

What was found

The abstract reports no numerical data, sample sizes, or effect estimates. It qualitatively describes that dietary fiber provides fermentable substrates for SCFA production while polyphenols modulate bacterial populations, with their combination exerting synergistic benefits on microbial diversity and intestinal barrier function dependent on fiber structure, polyphenol source and dose, and individual baseline microbiome profiles.

Why it matters

Clarifying how fibers and polyphenols interact provides a mechanistic basis for designing targeted functional foods and personalized nutritional interventions for metabolic health.

Limits

The abstract does not report a systematic search strategy, study counts, quality appraisal, or quantitative outcome measures. Clinical applicability is limited by reliance on broad narrative synthesis and high inter-individual microbiome variability.