Supplement
Fiber Supplement (Psyllium)
Useful when whole-food fiber falls short. Psyllium is the studied form.
What it does
Whole-food fiber is the default; psyllium is the fallback when intake stalls. Solid evidence for lipid lowering, glucose modulation, and regularity — a hedge against falling short, not a vegetable replacement.
Psyllium forms a viscous gel that binds bile acids (forcing the liver to spend cholesterol replacing them), slows carbohydrate absorption, and bulks stool.
What the evidence shows
Overall evidence strength: Moderate certainty
Who it's for, who should skip
When whole-food fiber falls short. Take with plenty of water and away from medications.
Running it
- Form
- oral
- Dose
- 5–15 g · daily · with plenty of water; separate from medications by 2 hr
Stacking & alternatives
Pair it with
- adequate water — Psyllium must be taken with plenty of water to form its gel safely and avoid obstruction.
Access & cost
Available over the counter. Look for: psyllium husk.
Last reviewed 27 August 2026.