Glucomannan (konjac root)
What it is
A highly viscous soluble fibre from the konjac root that expands dramatically in water, promoting fullness. EFSA approved a weight loss health claim for glucomannan at 3 grams per day alongside a calorie-controlled diet. The Sood et al. 2008 AJCN meta-analysis (14 studies) found glucomannan significantly reduces body weight, LDL cholesterol, and fasting glucose. Must be taken with plenty of water to avoid choking or oesophageal blockage.
Dose
1 g × 3 daily 30 min before meals with 250 mL water; EFSA-approved weight loss claim at 3 g/day
Time of day & tips
Take with a large glass of water (at least 250 mL) 30 min before meals. Do not take at bedtime or without water — choking risk. Separate from medications by 1 hour.
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