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.
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
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.