We use essential cookies (authentication, your saved goals/stack) by default. With your permission we'll also enable privacy-respecting analytics (Vercel Web Analytics, anonymous load-time metrics) and error-replay diagnostics (Sentry — DOM snapshots only when an error fires) so we can fix bugs faster. Learn more
Glucomannan (Konjac Root Fiber)
Absorbs up to 50x its weight in water, creating strong satiety — supports weight loss, blood sugar regulation, and cholesterol reduction.
What the evidence says
Glucomannan appears to help in 12 of 13 studies with measurable effects — the evidence leans clearly favourable.
Most evidence is from high-quality meta-analyses and randomised trials published 2005–2026 with a typical study size of 53 participants.
Based on 39 studies · 9 meta-analyses · 24 RCTs · 9,737 total participants
Confidence
HighWhat the studies found
By outcome
Glucomannan has an evidence score of 8.5/10 — very strong evidence based on 39 indexed studies, including 9 meta-analyses. Absorbs up to 50x its weight in water, creating strong satiety — supports weight loss, blood sugar regulation, and cholesterol reduction.
The commonly studied dose of Glucomannan is 1g three times daily before meals (3g total). Research points to an estimated optimal dose around 3g, with a minimum effective dose near 2g. Individual response varies — start low and adjust.
The best time to take Glucomannan is between meals. It can be taken on an empty stomach. Glucomannan is a highly viscous soluble fiber from konjac root that expands dramatically in the stomach, promoting satiety.
Green Tea Extract
Likely helpsConcentrated catechins from green tea that support metabolism, fat oxidation, brain health, and antioxidant defense.
Resistant Starch
Likely helpsBypasses small intestine digestion to feed colon bacteria that produce butyrate — supports blood sugar, gut integrity, and metabolic health.
Last reviewed May 2026 · evidence from 39 studies · how we score
This information is for educational purposes only. It is not a substitute for professional medical advice. Always consult a qualified healthcare provider before starting, stopping, or changing any supplement or medication.
Glucomannan is a water-soluble dietary fiber extracted from the root of the konjac plant (Amorphophallus konjac). It has an exceptional ability to absorb water - up to 50 times its weight - forming a thick gel in the stomach. This creates a strong sense of fullness, making it one of the most effective natural appetite suppressants. It also helps lower cholesterol and blood sugar by slowing nutrient absorption.
Absorbs water to form viscous gel
Slows carb and fat absorption
Feeds beneficial gut bacteria
How Glucomannan works — from molecular targets to health outcomes. Click an edge to see supporting research.This visualization is in beta — pathways are being refined and expanded.
1g three times daily before meals (3g total)
Loading: Not required; consistent pre-meal dosing is key
Can be taken without food
| Form | Type |
|---|---|
| 💊Capsules (safest) | Recommended |
| 🧪Powder (must mix thoroughly) | Alternative |
| 💊Konjac noodles (food form) | Alternative |
Capsules are safest to avoid choking. If using powder, mix well in water and drink immediately before it gels. Never take dry.
Minimum: 4 weeks
Optimal: 12 weeks
Cycling: Not required
Note: MUST be taken with plenty of water. Taking before meals creates satiety. Never take dry or with insufficient liquid.
Meta-analysis of 6 RCTs (n=225) showed modest but significant weight reduction vs placebo. Effects appear greater in females. Limited long-term data available.
Strong feeling of fullness
Modest but consistent weight reduction
Lowered LDL and total cholesterol
Can expand and block throat if not taken properly
One of the few supplements with proven weight loss effects
May enhance blood sugar lowering; monitor
May reduce absorption; take medications 1 hour before or 4 hours after
Tip: Start with lower dose; increase gradually
Tip: Reduce dose
Tip: ALWAYS take with plenty of water; never take dry
Glucomannan is generally safe at recommended doses, with a few precautions worth noting. The most commonly reported side effects are bloating and gas, loose stools, esophageal obstruction. Use caution if any of these apply to you: Esophageal stricture or swallowing difficulties; GI obstruction.
Spirulina
Likely helpsBlue-green algae with 60-70% complete protein and unique phycocyanin antioxidant — lowers cholesterol, blood pressure, and blood sugar.
Tap node to isolate • Pinch to zoom • Tap edge for research