Glucomannan (Konjac Fibre)

Weight lossCholesterolConstipation

A soluble fibre that swells in the stomach to ~50x its dry volume. The most evidence-backed natural appetite-suppressant fibre.

EvidenceStrong

Strong for modest weight loss in calorie-restricted diets, LDL cholesterol reduction (~10%), constipation, and blood sugar smoothing. Effects: 4–12 weeks.

Glucomannan is the soluble fibre extracted from the konjac plant root (same plant as shirataki noodles). When mixed with water it swells dramatically, producing satiety, slowing gastric emptying, and binding cholesterol and bile acids in the gut. EFSA-approved health claims for cholesterol reduction and weight loss in calorie-restricted diets. Important safety note: take with plenty of water — dry capsules can swell and obstruct the esophagus.

Form
Glucomannan powder (mix in water) or capsules.
Dose
1 g 3x daily, taken with a full glass of water before each main meal.
Timing
15–30 min before meals, with at least 240 mL water.
Schedule
Daily.
Side effects
Gas, bloating, mild GI upset (first 1–2 weeks). Esophageal obstruction if taken without enough water — never dry-swallow capsules.
Interactions
Reduces absorption of many oral medications (diabetes meds, levothyroxine, statins, etc.) — separate by 2 hours.
Contraindications
Difficulty swallowing. Esophageal strictures or motility disorders. GI obstruction history.
Lab markers
Lipid panel, weight tracking.
Food sources
Shirataki noodles (konjac noodles) deliver similar fibre as food.

Pairs with

Berberine, bergamot (metabolic stack). Caloric-restricted diet.