Evidence map›Paper›PMID 42514458›Full record

ReviewNutrients2026

Supplementation of γ-Aminobutyric Acid as a Functional Nutrient.

Wei-Yang Lu

Abstract readReview
In one paragraph

Review in Nutrients, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

1 author.

Wei-Yang LuDepartment of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON N6A 5B7, Canada.ORCID 0009-0006-2208-6660

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

γ-Aminobutyric acid (GABA) is an endogenous metabolite and signaling molecule that is widely distributed across plants, microorganisms, and mammalian tissues. Although classically viewed as the principal inhibitory neurotransmitter in the central nervous system, GABA also functions in peripheral organs, where it participates in receptor-mediated signaling, intermediary metabolism, epithelial barrier regulation, endocrine control, immune modulation, and host-microbiota communication. These features have renewed interest in oral GABA supplementation and in dietary or microbial strategies designed to increase luminal or circulating GABA availability. Despite increasing interest in oral GABA supplementation and microbiota-derived GABA, evidence remains fragmented across multiple disciplines and the translational relevance of peripheral GABA biology remains incompletely defined. This review considers GABA within a functional nutrient framework: not as an essential nutrient required to prevent deficiency, but as a nonessential bioactive metabolite whose exogenous availability may modulate physiological regulation under specific conditions. The literature was identified through structured PubMed searches of studies published from 2000 onward. This review summarizes current knowledge regarding exogenous sources of GABA, intestinal absorption, hepatic uptake, and metabolic fate, receptor-mediated and metabolite-mediated signaling mechanisms in peripheral tissues, and findings from experimental, preclinical, and clinical studies examining GABA supplementation in immune-, endocrine-, and metabolic-related contexts. The findings support GABA as a biologically active functional nutrient with potential roles in immune, endocrine, epithelial, hepatic, and metabolic regulation. While experimental studies consistently report beneficial effects on inflammatory and metabolic outcomes, human studies remain limited and have not yet established definitive clinical efficacy. Future studies should prioritize well-powered randomized controlled trials, dose-response analyses, long-term safety assessments, and biomarkers of tissue-specific GABA exposure and target engagement.

Indexed as

Dietary Supplementsgamma-Aminobutyric AcidNutrientsAnimalsHumansIntestinal AbsorptionLiverSignal Transductiongamma-Aminobutyric Acidfunctional nutrientGABA shuntgut microbiotahepatic metabolismimmune regulationintestinal absorptionmetabolic regulationγ-aminobutyric acid

Identifiers

PMID42514458
PMCPMC13414921

What OpenQuestion holds

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LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.