Metabolic & Cardiometabolic · Gut & Microbiome
secondary bile acids stimulates GLP-1
In plain terms: Do gut-bacteria bile acids boost your appetite-suppressing hormone GLP-1?
Yes as a mechanism, but only shown in animals so far — human evidence is correlational.
📅 Last reviewed: 2026-07-15 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: Animal studies (Animal)
How the studies fall
What the evidence shows
Microbe-generated secondary bile acids (DCA/LCA, taurine-conjugated) activate basolateral TGR5/GPBAR1 on L-cells to stimulate GLP-1 — robust in animal/ex-vivo models; the diet->microbe->secondary-BA->GLP-1 chain is causal in mice, human evidence is correlational only.
The evidence (16)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Meng Y et al 2026 · study_type: animal | animal | mixed | medium | Oat β-glucan raised gut secondary bile acids (LCA, DCA) in obese mice, which the authors show promote GLP-1 secretion 'via inhibiting FXR' — TGR5 is not invoked as the mediating receptor for the GLP-1 rise in this study. |
| Zhu 2024 · Altern Ther Health Med | animal | supports | moderate | Bile acid injection lowered glucose in T2DM rats via TGR5/GLP-1 rather than the FXR/FGF15 pathway. |
| Lv J et al 2026 · study_type: animal | animal | supports | medium | L. salivarius XA1416 raised UDCA in mice, improving glucose/GLP-1. Oral UDCA replicated effect: acts as intestinal FXR antagonist + TGR5 (GPBAR1) agonist to stimulate GLP-1. HepG2 cells + molecular dynamics show UDCA directly activates GLP- |
| Wang 2026 · J Pharm Biomed Anal | animal | supports | moderate | Liuwei Dihuang upregulated ileal TGR5 and enhanced GLP-1/PYY secretion via gut-microbiota-bile-acid axis in T2DM rats. |
| Zheng X, et al. 2021 · (HCA) | animal | supports | moderate | [FT-verified] Zheng 2021 CellMetab hyocholic acids via TGR5+FXR mouse+human corr. ANIMAL/MECHANISM |
| Sun 2024 · J Agric Food Chem | animal | supports | moderate | Mushroom polysaccharide raised conjugated ileal bile acids that stimulated TGR5, inducing GLP-1 release and better glucose metabolism. |
| Sun YH et al 2026 · study_type: animal | animal | supports | low | Herbal formula LGZG in HFD mice enriched non-12α-OH secondary bile acids (hyocholic acid, 7-ketoLCA) — known TGR5 agonists/FXR antagonists — which elevated serum GLP-1 and activated adipose TGR5-cAMP/PKA/CREB signaling and thermogenesis. |
| Yue 2024 · Food & Function | animal | supports | moderate | TGR5 agonist INT-777 restored ileal TGR5/proglucagon expression and serum GLP-1 suppressed by acrylamide in mice. |
| Stefela 2025 · Pharmacol Res | animal | supports | moderate | Dual FXR-antagonist/TGR5-agonist bile-acid analogue enhanced GLP-1 secretion and improved glucose homeostasis in Western-diet mice. |
| Zhang 2025 · Sci Transl Med | animal | supports | high | Intestinal TGR5-targeted deoxycholic-acid conjugate boosted GLP-1 secretion and glycemic control in mice and pigs. |
| Wang 2023 · Gut Microbes | animal | supports | high | Gut-microbiota-derived ileal bile acids (wMCA, HCA) drive postprandial GLP-1 via TGR5, not FXR, in mice. |
| Yu 2023 · Endocrine Journal | mechanism | supports | moderate | Review: intestinal GPBAR1/TGR5 activation by bile acids stimulates GLP-1, linking bile-acid signaling to glucose homeostasis. |
| Pathak P, et al. 2018 · (FXR/TauroLCA) | animal | supports | moderate | [FT-verified] Pathak/Chiang 2018 mouse microbiota+FXR activate TGR5 to improve metabolism. ANIMAL-only |
| Hui 2020 · FASEB J | animal | supports | moderate | Capsaicin raised lithocholic acid (LCA) via microbiota remodeling, an endogenous TGR5 agonist enhancing L-cell GLP-1 secretion. |
| Brighton CA, et al. 2015 · Endocrinology | mechanism | supports | moderate | [FT-verified] Brighton/Gribble 2015 murine/ex-vivo L-cell BA->GLP-1 via basolateral TGR5. ANIMAL/MECHANISM-only |
| Ma H et al 2026 · study_type: animal | animal | supports | high | Obesity-prone humans/mice show depleted GDCA (secondary bile acid). GDCA supplementation in obese mice improved weight/steatosis and stimulated ileal GLP-1 secretion by activating TGR5 signaling, alongside BAT thermogenesis; FMT recapitulat |
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