Fiber
Glucomannan (Konjac)
Also known as: Glucomannan (Konjac Root), Konjac fiber, Konjac glucomannan, Konjac root
Highly viscous fiber from konjac root. Strong satiety effects and blood sugar support.
Last reviewed June 2026 · Evidence graded from peer-reviewed research, not editorial opinion. Educational only — not medical advice.
Common questions
How much Glucomannan (Konjac) should I take?
The typical range is 1-3 g before meals. Safe long-term
When should I take Glucomannan (Konjac)?
30 min before meals. Before meals with water.
Which form of Glucomannan (Konjac) is best?
Capsules — Take before meals. Other forms in the catalog: Powder.
Is Glucomannan (Konjac) safe?
Commonly reported: Bloating, Loose stools. Serious warnings: Choking if insufficient water. Safe
Which Glucomannan (Konjac) supplement scores highest?
Nutricost Glucomannan Capsules, at 71/100. Scored on dose accuracy, form, label transparency and third-party testing — no brand pays to be listed or ranked.
Primary uses
- Weight management
- Satiety
- Blood sugar
- Cholesterol
How it works
- Absorbs 50x its weight in water
- Forms thick gel
- Slows gastric emptying
Dosage
- Typical range
- 1-3 g before meals
- Timing
- 30 min before meals
- With food
- Before meals with water
- Duration
- Safe long-term
- Special populations
- Weight management
Forms
- Capsules
- Powder
Safety
Common side effects
- Bloating
- Loose stools
Contraindications
- Swallowing difficulties
Products containing Glucomannan (Konjac)
Top-scoring supplements in our catalog that list Glucomannan (Konjac) on the label. Each product is graded on Formulate's ingredient-level rubric — dose accuracy, form, transparency, and third-party testing.
Evidence notes
Satiety and metabolic benefits
Grade B: Some human trials support key claims; further confirmation needed.
Related in Fiber
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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider. Individual needs and risks vary — consult a professional before starting, stopping, or combining supplements, especially if you are pregnant or nursing, taking medication, or managing a health condition.