Metabolic & Cardiometabolic
Does the prebiotic fiber GOS help control blood sugar?
The claim, precisely: galacto-oligosaccharides improves insulin sensitivity
Insufficient Metabolic & Cardiometabolic 🔬 Includes disconfirming
RefutedContestedStrong support
consensus score 0.29
Too early to say — it feeds good gut bacteria but the best trial showed no benefit.
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)
MechanismIn-vitroAnimalObservationalRCTMeta-analysis
How the studies fall
1 support 0 contradict 1 tested null 1 mixed · 3 sources, 1 independent group
What the evidence shows
GOS robustly raises bifidobacteria but does NOT improve insulin sensitivity, energy metabolism or plasma metabolites in obese prediabetics — a microbiome-claim ingredient, not a metabolic one.
The evidence (3)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Vulevic 2013 2013 · J Nutr | RCT | supports | moderate | B-GOS reduced fasting insulin, TC and TG in overweight adults |
| Canfora EE, et al. (Blaak) 2017 · Gastroenterology | RCT | tested-null | high | 12-wk GOS: null on insulin sensitivity/energy metabolism despite bifidobacteria rise |
| Vulevic 2015 2015 · Br J Nutr | RCT | mixed | moderate | B-GOS shifted microbiota/immune markers but no insulin-sensitivity improvement |
Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.