Supplements · Metabolic & Cardiometabolic
Does psyllium fibre lower the blood-sugar rise after meals?
The claim, precisely: psyllium attenuates postprandial glucose
Strong support Supplements
RefutedContestedStrong support
consensus score 1.00
Yes — strongly in people with diabetes, but barely at all in those with normal blood sugar.
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: All trials, pooled (Meta-analysis)
MechanismIn-vitroAnimalObservationalRCTMeta-analysis
How the studies fall
3 support 0 contradict 0 tested null 0 mixed · 3 sources, 3 independent groups
What the evidence shows
Psyllium attenuates glucose, with effect proportional to baseline dysglycemia — meaningful in T2D, near-null in euglycemic eaters.
The evidence (3)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Gibb RD, et al. 2015 · Am J Clin Nutr | meta-analysis | supports | moderate | FBG/HbA1c improvement greatest in T2D; negligible in euglycemics (Metamucil-maker funding) |
| Pastors 1991 · Am J Clin Nutr | RCT | supports | moderate | Psyllium with meals cut peak postprandial glucose rise 14-20% in NIDDM; insulin also lower |
| Anderson 1999 · Am J Clin Nutr | RCT | supports | moderate | RCT 34 T2D men: 5.1g psyllium twice daily cut postlunch glucose 19.2% and all-day glucose 11% |
Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.