Glucomannan Root Extract
Also known as: Konjac mannan, Konjac fiber, Konjac glucomannan, Glucomannan
Overview
Glucomannan is a soluble dietary fiber derived from the root of the konjac plant (*Amorphophallus konjac*), traditionally used in Asian cuisine and medicine. This polysaccharide is known for its exceptional water-absorbing capacity, which contributes to its fibrous nature. Glucomannan is employed in various dietary applications, primarily to alleviate constipation, manage blood sugar levels, and improve cholesterol profiles. Additionally, it is marketed for weight loss, although evidence supporting this claim is less robust. As a soluble fiber, glucomannan can form a gel-like substance in the gut, which can help slow down the absorption of sugars and cholesterol, leading to various health benefits. The body does not absorb glucomannan but utilizes its effects locally within the gastrointestinal tract, making it effective for promoting bowel regularity and digestive health. Research on glucomannan has yielded moderate maturity, with several systematic reviews indicating its benefits, especially in constipation and lipid control, though findings on weight loss are inconsistent.
Benefits
Glucomannan has several evidence-based benefits: It significantly increases defecation frequency in children with constipation, as demonstrated in a meta-analysis showing a mean difference of 1.40 more defecations per week. Additionally, glucomannan may reduce cholesterol levels and improve glycemic control in individuals with diabetes, as reported in systematic reviews. However, while it is marketed for weight loss, a systematic review has not found statistically significant results regarding its efficacy in this regard. Other potential benefits include modest effects on blood pressure, though evidence is not robust. The most significant benefits appear within a few weeks of consistent usage, particularly for managing constipation and lipid profiles.
How it works
Glucomannan's primary mechanism involves its ability to absorb water in the gastrointestinal tract, forming a bulky gel that promotes satiety, slows digestion, and reduces the absorption of sugars and cholesterol. This bulking action also aids in fecal bulk formation, facilitating regular bowel movements. As a soluble fiber, it interacts primarily with the gut, impacting motility and nutrient absorption. While there are no specific molecular targets identified, its physiological effects are predominantly mechanical.
Side effects
Glucomannan is generally considered safe for most individuals when taken with adequate fluid to minimize choking risks. Common side effects (>5% incidence) include abdominal discomfort, diarrhea, and constipation. Less frequent adverse effects (1-5%) reported include gastroenteritis, vomiting, and pruritus, particularly in children. While no rare side effects (<1%) are documented, caution is advised in individuals with gastrointestinal disorders or swallowing difficulties. It may interact with medications by affecting their absorption due to its bulking properties. Special populations, including children and the elderly, should ensure sufficient fluid intake to avoid choking hazards, as these groups are more susceptible.
Dosage
For effective use, glucomannan is typically recommended at doses of 2-4 grams per day for managing constipation and lipid profiles. The minimum effective dose begins at around 2-3 grams. Despite its marketing for weight loss, there is insufficient evidence to endorse a specific dosage for this purpose. It is advisable to take glucomannan before meals to augment feelings of fullness and improve absorption. Common forms include capsules and powders, and it is crucial to consume ample water with glucomannan to prevent choking. Although doses exceeding 5 grams are not widely studied, there are currently no established maximum limits.
FAQs
Is glucomannan safe?
Yes, glucomannan is considered safe if taken with adequate fluids to prevent choking risks, particularly for children and the elderly.
What is the best time to take glucomannan?
It is recommended to take glucomannan before meals to aid satiety and nutrient absorption.
How long does it take to see results?
You may notice relief from constipation and improvements in lipid and glucose profiles within a few weeks of consistent use.
Does glucomannan aid in weight loss?
While marketed as a weight loss supplement, glucomannan lacks significant evidence for efficacy in promoting weight loss.
Research Sources
- https://pubmed.ncbi.nlm.nih.gov/24533610/ – This systematic review and meta-analysis included 9 RCTs focusing on weight loss involving glucomannan. It concluded that there is no statistically significant difference in weight loss outcomes when compared to placebo.
- https://www.mdpi.com/2304-8158/12/11/2122 – A systematic review and meta-analysis focusing on the impact of glucomannan on constipation in children. It found that glucomannan significantly increased defecation frequency, indicating its efficacy for this specific population.
- https://apjcn.nhri.org.tw/server/APJCN/26/3/471.pdf – This study examines various fiber supplements, including glucomannan, and their effects on metabolic syndrome. Results indicated that glucomannan effectively reduced BMI and body weight in participants following an energy-restricted diet.
Supplements Containing Glucomannan Root Extract
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