Metabolic & Cardiometabolic · Gut & Microbiome
Does a bile acid taken by mouth boost an appetite hormone in people?
The claim, precisely: oral bile acid (CDCA) increases GLP-1
Probably yes for the bile acid itself, but whether ordinary diet can do the same is unproven.
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: Human trials (RCT / n-of-1)
How the studies fall
What the evidence shows
Direct chenodeoxycholic acid raises GLP-1 in humans (intragastric, and post-RYGB), but bile-acid SEQUESTRANTS do not raise GLP-1 in humans despite lowering glucose — so the human glucose benefit of sequestrants is not GLP-1-mediated. Bile acids CAN drive human GLP-1; whether diet can is unproven.
The evidence (4)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| (colesevelam RCT) 2013 · (human RCT) | RCT | tested-null | moderate | n=38 RCT 12wk: improved glycemia but postprandial GLP-1 UNCHANGED (mechanism = glucose sequestration) |
| (CDCA post-RYGB) 2017 · (human crossover) | RCT | supports | moderate | Oral CDCA raised GLP-1/PYY/FGF19 in post-RYGB (n=11); UDCA did not |
| Hansen M, et al. (Knop) 2016 · (human crossover) | RCT | supports | moderate | Intragastric CDCA increased plasma GLP-1 (human crossover) |
| (Knop, colesevelam) 2024 · (human crossover) | RCT | tested-null | moderate | Single-dose colesevelam: no acute postprandial GLP-1 rise |
Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.