Prebiotics
Prebiotics are substances, mostly types of fiber such as inulin, that gut microbes selectively feed on.
Which benefit is well defined?
The EU permits a claim that native chicory inulin increases stool frequency, with 12 g daily specified for the effect. This concerns that particular ingredient and outcome, not every product labeled prebiotic. 1
Support is specific to increased stool frequency with native chicory inulin, not every cause of constipation. 1
Does the starting point matter?
Two small crossover trials tested 10 g inulin daily. One increased stool frequency and the other did not; combining participants with genuinely low baseline frequency showed an increase from about four to five bowel movements weekly. 2
Can prebiotics help an irritable bowel?
An analysis of 11 trials in 729 adults with functional bowel disorders found no overall improvement in symptoms or quality of life. Bifidobacteria increased, yet inulin-type fructans worsened flatulence; none of the trials had low risk of bias in every category. 3
Ingredient and dose affected tolerability; more bifidobacteria did not mean better symptom relief. 3
What does a microbiome change prove?
A review of human metabolic research describes substantial differences between people. A proposed fermentation pathway should therefore be distinguished from a demonstrated clinical benefit for a particular supplement. 4
Effects by health goal
Open an effect to see the studies behind its rating. Bars show the size of the effect; the letter grades the evidence.
Gut Health5 effects
No study is linked to this rating.
No study is linked to this rating.
Immune Support1 effect
Other effects2 effects
All studies
15 publications are linked to Prebiotics, newest first.
Sources
- Commission Regulation (EU) 2015/2314 European Commission, 2015
- Prebiotics in irritable bowel syndrome and other functional bowel disorders in adults: a systematic review and meta-analysis of randomized controlled trials American Journal of Clinical Nutrition, 2019