Glucomannan

Best for

Lose weight on the scale

Likely strong benefit · 1.2–15 g/day for 2–52 weeks · 1 meta-analysis , n=238

6 papers · 4 claims · 24 outcomes scored · 2 positive

Outcomes

What glucomannan actually does, by outcome

Each row is one outcome with effect size, evidence base, the dose that worked in trials, and time to first effect. Magnitude tiers come from native-unit MCID where available, Cohen's d otherwise.

Outcome Effect size Evidence Dose Weeks Rank

Lose weight on the scale Likely strong benefit

Less weight on your joints, better blood markers, easier movement.

3 meta-analyses n=238 1.2–15 g 2–52 wk #2/75

24490058·27891167·36771306

large

3 meta-analyses n=238 Meta-analyzed

1.2–15 g

2–52 wk

#2 /75

Lose body fat Faint early signal

Body fat percentage drops and the mirror shows it before the scale does.

2 RCTs n=68 3.99–15 g 8–52 wk

24490058·27891167

small

2 RCTs n=68

3.99–15 g

8–52 wk

—

Feel full longer and crave less Not enough research

Genuine satiety replaces the constant urge to snack or overeat.

1 RCT n=— 3.99 g 8 wk

24490058

—

1 RCT n=—

3.99 g

8 wk

—

Reduce belly and deep abdominal fat Not enough research

Targets the visceral fat that wraps around your organs and drives inflammation.

1 RCT n=— 3.99 g 8 wk

24490058

—

1 RCT n=—

3.99 g

8 wk

—

Outcome	Effect	Evidence	Dose	Weeks	Rank
Lose weight on the scale Likely strong benefit	large	3 meta-analyses n=238 Meta-analyzed	1.2–15 g	2–52 wk	#2/75
Lose body fat Faint early signal	small	2 RCTs n=68	3.99–15 g	8–52 wk	—
Feel full longer and crave less Not enough research		1 RCT n=—	3.99 g	8 wk	—
Reduce belly and deep abdominal fat Not enough research		1 RCT n=—	3.99 g	8 wk	—

Risk profile

Adverse events and known drug interactions

Safety events

esophageal_obstruction severe

oesophageal_perforation severe

esophageal obstruction severe

dysphagia moderate

belching mild

bloating mild

stomach fullness mild

Gastrointestinal adverse events (flatulence, diarrhoea) mild

Sources

Generated August 14, 2026

Glucomannan

What glucomannan actually does, by outcome

Adverse events and known drug interactions

More evidence for Glucomannan

Metabolic health: evidence map across 82 supplements

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Glucomannan

More evidence for Glucomannan

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NewBerberine

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NewChlorella

NewChlorogenic Acid

NewChromium

Metabolic health: evidence map across 82 supplements

Berberine

Chitosan

Chlorella

Chlorogenic Acid

Chromium