Research

Mixed

Dietary fiber promotes the production of beneficial tryptophan metabolites, specifically indolelactic acid (ILA) and indolepropionic acid (IPA), by making more tryptophan available for Stickland fermentation.

To support gut health and potentially reduce the production of harmful metabolites like indole, incorporate fermentable fibers (such as pectin found in apples) into your diet. This encourages beneficial bacteria to produce protective metabolites (ILA, IPA) and suppresses the production of indole, which is linked to chronic kidney disease risk.

GoodSupportsHIGH confidence
Our findings explain why consumption of fermentable fibres suppresses indole production but promotes the generation of other tryptophan metabolites associated with health benefits.
Anurag Kumar Sinha et al. · Nature Microbiology · 2024

Why this rating

Strong evidence from in vitro, gnotobiotic mouse, and human fecal culture models, though direct long-term human clinical outcomes on CKD are inferred from metabolite levels.

Source

Dietary fibre directs microbial tryptophan metabolism via metabolic interactions in the gut microbiota

Anurag Kumar Sinha et al. · Nature Microbiology · 2024

DOI 10.1038/s41564-024-01737-3

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

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