Metabolic & Cardiometabolic · Gut & Microbiome
Do gut-bacteria bile acids boost your appetite hormone?
The claim, precisely: secondary bile acids stimulates GLP-1
Yes as a mechanism, but only shown in animals so far — human evidence is correlational.
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 (6)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Zheng X, et al. 2021 · (HCA) | animal | supports | moderate | [FT-verified] Zheng 2021 CellMetab hyocholic acids via TGR5+FXR mouse+human corr. ANIMAL/MECHANISM |
| Zheng X, et al. 2021 · (HCA) | animal | supports | moderate | Hyocholic acid species dual TGR5-agonist/FXR-antagonist raise GLP-1; low serum HCA assoc. with human diabetes |
| Pathak P, et al. 2018 · (FXR/TauroLCA) | animal | supports | moderate | Intestinal FXR agonist + microbiota -> tauroLCA -> TGR5 -> GLP-1; antibiotics reversed it |
| 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 |
| 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 |
| Brighton CA, et al. 2015 · Endocrinology | animal | supports | high | TDCA>TCA via basolateral GPBAR1; abolished in GPBAR1-KO; luminal needs ASBT |
Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.