Unveiling of dietary and gut-microbiota derived B vitamins: Metabolism patterns and their synergistic functions in gut-brain homeostasis.
Level 5 - mechanism / opinion, no new human data
Narrative review of mechanistic literature with no primary human data or systematic search
PubMed 36271691 · doi:10.1080/10408398.2022.2138263
What was done
This narrative review synthesizes literature on dietary and microbiota-derived B-vitamin metabolism. The authors describe the division between prototrophic and auxotrophic gut bacteria, mechanisms of syntrophic B-vitamin cross-feeding, transport and absorption across the proximal and distal gastrointestinal tract, and proposed roles of B vitamins as psychobiotics influencing brain energy metabolism and the kynurenine/tryptophan pathway.
What was found
The abstract reports no quantitative measurements, effect sizes, or numerical data. It presents conceptual models regarding bacterial B-vitamin exchange, community-level microbiome dynamics, intestinal absorption pathways, and the neurological consequences of B-vitamin deficiencies.
Why it matters
The review maps how commensal microbes and dietary inputs jointly supply B vitamins, framing bacterial micronutrient exchange as a potential modifier of microbiome composition and gut-brain metabolic communication.
Limits
The paper is a narrative overview rather than a systematic review or clinical trial, with no systematic search criteria reported. The abstract provides only mechanistic concepts without primary human data, sample sizes, or empirical effect estimates.