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Fiber

Konjac Root Extract (Amorphophallus konjac)

Also known as: glucomannan, konjac glucomannan, konjac flour, elephant foot yam

B
Evidence

Konjac root extract is a soluble dietary fiber derived from the konjac plant, primarily composed of glucomannan, which absorbs water and forms a viscous gel in the digestive tract. Evidence supports its use for promoting digestive health, blood sugar management, and modest weight loss support.

Primary uses

  • Digestive health and regularity
  • Blood sugar management
  • Cholesterol support
  • Weight management support
  • Satiety and appetite control

How it works

  • High-viscosity soluble fiber that absorbs water and slows gastric emptying
  • Increases fecal bulk and promotes bowel regularity
  • Reduces glycemic response by slowing carbohydrate absorption
  • May lower cholesterol by binding bile acids
  • Promotes satiety through gastric distension

Dosage

Typical range
3-15 g daily (1.5-5 g per serving, 2-3 times daily)
Timing
Take with meals or separate doses throughout the day
With food
Must be taken with at least 8 oz (240 ml) of water or liquid; can be mixed into beverages
Duration
Safe for long-term daily use; effects on bowel regularity typically observed within 3-7 days
Special populations
Start with lower doses (3-5 g daily) and increase gradually to minimize gas and bloating; persons with difficulty swallowing should avoid or use with caution; inadequate fluid intake increases choking and obstruction risk

Forms

  • Powder· 70/100
  • Capsules· 70/100
  • Tablets· 70/100

Safety

Common side effects

  • Bloating and gas (dose-dependent, often transient)
  • Abdominal discomfort or cramping
  • Constipation if inadequate water intake

Contraindications

  • Dysphagia (difficulty swallowing)
  • Esophageal strictures or obstruction
  • Bowel obstruction or ileus
  • Acute abdominal conditions
  • Severe dehydration or inadequate fluid intake

Evidence notes

Multiple RCTs and systematic reviews support efficacy for bowel regularity, modest glycemic control, and cholesterol reduction. Evidence for weight loss is moderate but present. Well-established safety profile with decades of use in food applications.

Grade B: Some human trials support key claims; further confirmation needed.

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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider.