IngredientsKonjac glucomannan (KGM) is a dietary fiber hydrocolloid derived from Amorphophallus konjac tubers and is widely utilized as a food additive and dietary supplement. The plant carries the scientific names Amorphophallus konjac Koch. and Amorphophallus rivieri Durieu ex Rivière. Common names include glucomannan, gonyak, konjac, konjac mannan, and konnyaku.
Konjac is a perennial herbaceous plant belonging to the genus Amorphophallus in the family Araceae, which mainly originated in the Indochina Peninsula and southern Yunnan in China, and its underground corms are rich in konjac glucomannan (KGM). The plant is native to Southeast Asia and prefers warm subtropical to tropical climates, requiring well-drained, nutrient-rich soils that retain moisture without becoming waterlogged.
Konjac glucomannan is a high molecular weight polysaccharide made up of blocks of mannose and glucose residues that are connected by Ξ²-(1β4) glycosidic bonds, with a ratio of 1.6:1.0 mannose to glucose residues within the polysaccharide in a random order. This linear structure is generally interspersed with branches on C3 of the sugar residues, connected via a Ξ²-(1β3) linkage, at approximately every tenth hexose unit, with an esterified acetyl group at approximately every nineteenth residue, contributing to a high solubility of the glucomannan in water.
Glucomannan is mainly a straight-chain polymer, with a small amount of branching. The component sugars are Ξ²-(1β4)-linked D-mannose and D-glucose in a ratio of 1.6:1. The degree of branching is about 8% through Ξ²-(1β6)-glucosyl linkages.
Konjac glucomannans are high molecular weight polymers where the molecular weight typically exceeds 1Γ106 daltons. In general, the natural gum has a high molecular weight and forms a viscous mixture or gel upon contact with water or an aqueous solution. The molecular weight distribution of natural gums can range from about 200,000 to about 20,000,000.
Glucomannan is not exclusively sourced from konjac. Glucomannans can be isolated from a variety of natural sources including eastern white pine (Pinus strobus), higanbana (Lycoris radiata), konjac (Amorphophallus konjac), lily (Lilium auratum), orchid (Tubera salep), ramie (Boehmeria nivea), and redwood (Sequoia sempervirens). However, most commonly, glucomannan is isolated from konjac root.
The content of konjac glucomannan (KGM) in konjac is up to 60%; konjac glucomannan is a high-viscosity, nutrient-low, water-soluble polysaccharide that exhibits swelling. While glucomannan and konjac flour are often used to mean the same thing, strictly speaking konjac flour is the raw, ground-up powder of the root, while glucomannan is the purified, active compound extracted from the root.
Processing typically involves washing, slicing, and drying the corms to obtain the soluble fiber used in various applications, including food products and dietary supplements. Konjac flour exhibits culinary versatility, being crafted into noodles, tofu, and vegetarian meat for human consumption. Glucomannan is available as a supplement in capsules and powder form and is added to some diet foods such as very low-carb pastas and noodles.
As a food additive, the flour produced from konjac corms is used as a gelling and thickening agent and is a permitted food ingredient in Europe as E425. KGM produces a heat-stable gel with an alkaline coagulant, a culinary tradition rooted in Japanese cuisine. At low concentrations, KGM is capable of forming a strong gel (KGM-gel) that is approximately 97% water when in the presence of a coagulant, representing one of the lowest energy-density foods available.
Traditionally, KGM has been utilized in Chinese medicine for over 2,000 years, serving various health purposes such as detoxification, tumor suppression, and treatment of respiratory and skin disorders. Amorphophallus konjac has a rich cultural and medical history, particularly in East Asia.
Its historical significance is underscored by its first documentation in the 'Shen Nong Materia Medica' during the Western Han Dynasty, which highlights its longstanding role in ancient Chinese medicine. Konjac glucomannan was first used and studied by the Chinese, and its medicinal properties were first described in the Shen Nong Materia Medica during the Western Han Dynasty (ca. 206 BC to 08 AD).
Glucomannan has been used in Asia, particularly in China, for over 2,000 years in applications for detoxification, tumor suppression, blood stasis alleviation, and to treat ailments such as asthma, cough, hernia, breast pain, burns, as well as hematological and skin disorders.
Konjac flour has been traditionally produced through processing corms, the underground storage organs. After boiling with plant ash, the flour is consumed as cake or gel. In the 6th century AD, konjac glucomannan was introduced to Japan as a medicinal product.
This historical context underscores the significance of konjac in both dietary and medicinal practices, highlighting its role as a staple food source in countries like China and Japan. Konjac corms have been grown as food for centuries in Asia, where they have provided a source of food with very interesting physical characteristics.
Konjac has been widely used as a culinary ingredient and traditional Chinese medicine in Asian countries for thousands of years. The main component of the konjac tuber is konjac glucomannan (KGM), a kind of hydrocolloid dietary fiber. The corm also contains alkaloids, starch, proteins, soluble sugars, and special substances such as Ξ²-carotene.
Glucomannan forms a highly viscous sol when constituted with water at concentrations of pure glucomannan above 1.0% w/w. It is the only biopolymer currently known to form an aqueous gel at room temperature. The gel forms within a few minutes of mixing with water. KGM has the highest hydrated volume at the lowest concentration of any dietary fiber. Therefore, oral KGM can instill a feeling of fullness at a lower dose than other fiber supplements.
Gastric expansion and satiety signaling: KGM slows gastric emptying by forming a viscous gel of large volume, which increases the feeling of satiety. Appetite reduction may be through increasing gastric retention and delaying gastric emptying by the "mass effect" of a gel-like viscous mass forming in the stomach that triggers afferent vagal signals of fullness.
Gut hormone regulation: Dietary fiber induces greater satiety compared to simple sugars, potentially due to its physical properties, such as bulking and alteration of the viscosity of gastric contents. This effect may delay gastric emptying, blunt postprandial glucose and insulin responses, and influence the secretion of gut peptide hormones that regulate satiation. High-viscosity KGM more effectively stimulates enteroendocrine cells to release glucagon-like peptide-1 (GLP-1) and reduces ghrelin production, thereby activating hypothalamic neurons and moderating short-term satiety.
Bile acid binding: Glucomannan binds bile acids in the intestine, preventing their reabsorption in the terminal ileum and increasing fecal bile acid excretion. The liver synthesizes new bile acids from cholesterol, reducing circulating LDL.
Carbohydrate hydrolase inhibition: A second mechanism is the inhibition of carbohydrate hydrolases (Ξ±-amylase and Ξ±-glucosidase) in the small intestine. The dissolved KGM, in a gel state, can wrap nutrients, slow down the flow of food in the digestive tract, prolong the residence time of food paste in the gastric cavity, form a protective membrane barrier, and effectively inhibit the value of postprandial blood glucose.
Colonic fermentation and prebiotic activity: Fermentable fibers are consumed by intestinal bacteria, producing short-chain fatty acids that impact gene expression, including genes associated with obesity and metabolic health. Konjac gum and konjac glucomannan are unlikely to be absorbed intact and are significantly fermented by intestinal microbiota.
Inflammatory pathway modulation: Effects are mediated through inhibition of inflammatory pathways (e.g., NF-ΞΊB, MAPK), modulation of lipid metabolism genes (e.g., CD36), and regulation of neurotransmitters (e.g., GABA, 5-HT).
Body weight reduction is the area with the most clinical trials and the most regulatory attention, but the evidence remains mixed and contested depending on how studies are pooled and interpreted.
Meta-analysis evidence (Sood et al., 2008 β American Journal of Clinical Nutrition): Fourteen studies (n = 531) met the inclusion criteria. The use of glucomannan significantly lowered total cholesterol (WMD: β19.28 mg/dL; 95% CI: β24.30, β14.26), LDL cholesterol (WMD: β15.99 mg/dL; 95% CI: β21.31, β10.67), triglycerides (WMD: β11.08 mg/dL; 95% CI: β22.07, β0.09), body weight (WMD: β0.79 kg; 95% CI: β1.53, β0.05), and fasting blood glucose (WMD: β7.44 mg/dL; 95% CI: β14.16, β0.72). The use of glucomannan did not appear to significantly alter any other study endpoints.
Meta-analysis evidence (Onakpoya et al., 2014 β Journal of the American College of Nutrition): A separate systematic review and meta-analysis searching Medline, Embase, AMED, and the Cochrane Library reached a more negative conclusion. The evidence from available RCTs does not show that glucomannan intake generates statistically significant weight loss. A meta-analysis (random effect model) of 8 RCTs revealed a non-statistically significant difference in weight loss between glucomannan and placebo (mean difference: β0.22 kg; 95% CI: β0.62, 0.19; IΒ² = 65%).
Meta-analysis evidence (Keithley et al., 2020 β systematic review in overweight/obese adults): Out of 134 citations, 6 trials that enrolled 225 subjects were included. Glucomannan resulted in significant reduction in weight (WMD: β0.96 kg; 95% CI: β1.81 to β0.11, P = 0.02) (IΒ² = 88.1%, P < 0.001). There are conflicting reports about the effect of glucomannan in weight control, which may be due to the variations in the intervention dose, participants, sample sizes, study durations and overall methodological quality.
Systematic review evidence (Zalewski et al., 2015): In otherwise healthy overweight or obese adults, there is some evidence that in the short term, glucomannan may help to reduce body weight, but not BMI. Data in children are too limited to draw any conclusions.
Children: An expert panel sponsored by the U.S. National Heart, Lung, and Blood Institute stated that "glucomannan does not significantly improve weight loss" in children.
EFSA regulatory position: The EFSA NDA Panel concluded that a cause-and-effect relationship has been established between the consumption of glucomannan and the reduction of body weight. In order to obtain the claimed effect of reduction of body weight, at least 3 g of glucomannan should be consumed daily in three doses of at least 1 g each, together with 1β2 glasses of water before meals, in the context of an energy-restricted diet. The target population is overweight adults.
Evidence strength: The overall evidence is mixed and modest. The largest and most recent meta-analyses show statistically significant but very small weight reductions (less than 1 kg on average), with considerable heterogeneity across trials. EFSA has authorized a qualified health claim, but independent meta-analyses disagree on whether the effect is statistically significant. Effects in children are not established.
Meta-analytic evidence (Sood et al., 2008): The use of glucomannan significantly lowered total cholesterol (WMD: β19.28 mg/dL; 95% CI: β24.30, β14.26), LDL cholesterol (WMD: β15.99 mg/dL; 95% CI: β21.31, β10.67), and triglycerides (WMD: β11.08 mg/dL; 95% CI: β22.07, β0.09).
EFSA regulatory position: Cause-and-effect relationships have also been established between the consumption of glucomannan (konjac mannan) and maintenance of normal blood cholesterol concentrations. To obtain this effect, a food should provide at least 4 g/day of glucomannan in one or more servings. The conditions and restrictions of use for the health claims for glucomannan to contribute to weight loss and to the maintenance of normal blood cholesterol concentrations are authorized by Commission Regulation (EU) No 432/2012.
Evidence strength: Moderate to good. The cholesterol-lowering effect of glucomannan is the best-supported of its clinical applications, underpinned by a meta-analysis of 14 RCTs and an authorized EU health claim. The bile acid binding mechanism is well described and consistent with observed outcomes.
Meta-analytic evidence in type 2 diabetes (2023, PMC): Glucomannan not only reduced total cholesterol (MD β0.38 [95% CI: β0.61, β0.15], p = 0.001) and LDL levels (MD β0.35 [95% CI: β0.52, β0.17], p < 0.0001) compared with the control group, but also reduced fasting blood glucose (MD β1.08 [95% CI: β1.65, β0.50], p = 0.0002), 2-hour postprandial blood glucose (MD β1.92 [95% CI: β3.19, β0.65], p = 0.003), fasting insulin (MD β1.59 [95% CI: β2.69, β0.50], p = 0.004), and serum fructosamine levels (SMD β1.19 [95% CI: β1.74, β0.64], p < 0.0001). The analysis indicates that glucomannan is an effective nutritional intervention for type 2 diabetes.
Konjac glucomannan intake 30 minutes before performing the oral glucose tolerance test could lower the rise of blood glucose in comparison with the placebo. Some mechanisms described for soluble dietary fiber action include the increase in chyme viscosity to the production of short-chain fatty acids resulting from fermentation, which stimulates gastrointestinal motility and the release of GLP-1 and PYY hormones.
EFSA review: A cause-and-effect relationship has not been established between the consumption of glucomannan and claims relating to reduction of post-prandial glycaemic responses, maintenance of normal blood glucose concentrations, or maintenance of normal fasting blood concentrations of triglycerides β these claims were assessed by EFSA as not supported at the time of their 2010 opinion, though subsequent RCT data (reviewed above) has shown statistically significant effects in specific diabetic populations.
Evidence strength: Moderate. Several RCTs and a recent meta-analysis support meaningful reductions in fasting and postprandial glucose in type 2 diabetics. However, clinical effect sizes are modest, most trials have small sample sizes, and EFSA's 2010 assessment did not support glucose-related health claims. More recent pooled data are more favorable.
Soluble fibers, particularly konjac glucomannan (KGM), have shown potential in alleviating constipation, but clinical evidence, especially in specific populations, is limited. A 2025 double-blind RCT examined KGM's effects in elite Taekwondo athletes with functional constipation diagnosed by Rome IV criteria. Konjac glucomannan significantly ameliorated gastrointestinal symptoms in elite athletes with functional constipation, potentially via modulation of the gut microbiota.
In 2010, the EFSA NDA Panel prepared a scientific opinion on the substantiation of health claims in relation to glucomannan and, among other effects, maintenance of normal bowel function and decreasing potentially pathogenic gastrointestinal microorganisms. A cause-and-effect relationship has not been established between the consumption of glucomannan and these claimed effects under EFSA's criteria for authorized claims.
Evidence strength: Preliminary to moderate. Some individual RCTs and mechanistic evidence support a laxative/bulking effect, consistent with the general fiber literature. EFSA declined to authorize a bowel function health claim at the time of its assessment, though newer research continues to emerge.
KGM is a highly effective prebiotic that exerts a pivotal influence on regulating the composition and structure of gut microbiota. An increasing body of evidence underscores the robust correlation between gut microbial diversity and human health, encompassing its significance in a wide array of diseases.
Recent evidence indicates that KGM supplementation positively influences the structure of gut microbiota, altering important microbial populations linked to obesity. The intestinal microbiome has a role in host metabolism, and some bacterial taxa, such as Bacteroidetes and Akkermansia muciniphila, alter the production rate of short-chain fatty acids such as butyrate and propionate, which play a key role in metabolic regulation.
Current clinical use is limited by dose-dependent adverse effects and interindividual response variability, which stem from different microbial communities. This necessitates personalized dosage strategies.
Evidence strength: Preliminary. The mechanistic and preclinical evidence for prebiotic activity is consistent and compelling. However, direct human clinical evidence for specific prebiotic health outcomes from glucomannan remains limited, with most data extrapolated from animal models or indirect markers.
Glucomannan has been investigated for its effects on weight reduction, diabetes, constipation, cholesterol, lung cancer, and atopic diseases, as well as its use as a prebiotic. There are issues of quality concerning the evidence to support use for these indications.
Beyond its gastronomic applications, konjac gum and extract demonstrate therapeutic potential, serving as auxiliary treatments for conditions including hemostasis, tumors, cough, asthma, and diabetes. However, clinical evidence for these uses is either very limited or derived primarily from preclinical (animal/in-vitro) research and cannot be considered established based on current published RCT data.
Cancer prevention is currently speculative. Some preclinical evidence for cancer prevention via bile acid binding mechanisms exists, but clinical outcome translation is limited.
Clinical studies of glucomannan in diabetes, cholesterol control, and obesity have used dosages of 1 to 13 g daily.
EFSA-authorized doses:
Pediatric dosing in research protocols: In one pediatric RCT protocol, children aged 6β17 years were randomly assigned to receive glucomannan or placebo (maltodextrin), both at a dose of 3 g/day, for 3 months.
Precancerous marker study: KGM capsules at 4.5 g/day could significantly reduce the production of precancerous markers of colorectal cancer after four weeks of supplementation in subjects with a low-fiber diet.
Adverse effects at higher doses: After a daily dosage of 3,000 mg in adults for 12 weeks, several individuals experienced abdominal discomfort including diarrhea or constipation.
Dosage forms: Glucomannan is available as a supplement in capsules and powder, and is added to some diet foods such as very low-carb pastas and noodles. It is also a permitted food additive (Europe: E425) used as a gelling and thickening agent.
EFSA's Panel concluded that there was no need for a numerical acceptable daily intake (ADI) and that there was no safety concern for the general population at the refined exposure assessment for the reported uses of konjac gum (E 425 i) and konjac glucomannan (E 425 ii) as food additives under the current conditions of use of 10 g/kg.
The available database on toxicological studies was considered limited; however, no relevant adverse effects were seen in rats and dogs in 90-day feeding studies according to the SCF, the no-observed-effect level (NOEL) in rats being 1,250 mg konjac glucomannan/kg bw per day. Konjac gum and konjac glucomannan were of no concern with respect to genotoxicity.
Konjac flour (INS 425) was evaluated by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) in 1993 and 1996. In 1993, the Committee allocated a temporary ADI "not specified" for konjac flour. In 1996, an ADI "not specified" was allocated.
This is the most serious documented, non-theoretical safety concern for glucomannan supplements. A health advisory was released by Health Canada stating that natural health products containing the ingredient glucomannan in tablet, capsule or powder form have a potential for harm if taken without at least 250 ml (8 ounces) of water or other fluid. The risk includes choking and/or blockage of the throat, esophagus or intestine, according to international adverse reaction case reports. It is also important to note that these products should not be taken immediately before going to bed.
The obstruction is associated with the great capacity of konjac glucomannan to absorb water. The flour has been used in gums throughout the world but use for this purpose was recently banned in Europe because of the death of eighteen people as a consequence of choking.
The FDA considers konjac glucomannan a safe ingredient in dietary supplements but warns against using large tablets or capsules due to choking risk. When used in jelly candies for children, EFSA and FDA have noted a choking risk, so in some countries such products are restricted or prohibited.
Other adverse effects include diarrhea, belching, and bloating; in one study, people taking glucomannans had higher triglyceride levels. These effects are generally mild and transient, with more pronounced gastrointestinal discomfort reported at higher doses.
Glucomannan may affect the absorption of some medicines. The interactions between glucomannan and medicines are not fully understood. As with most dietary supplements, the research on drug interactions with glucomannan is incomplete.
Theoretically, taking glucomannan orally could hinder the absorption of medications, herbal products, other dietary supplements, or nutrients from foods consumed simultaneously. It is advisable not to take medications or herbal products within 2 hours of glucomannan.
Of particular note regarding blood glucose-lowering drugs: since glucomannan may lower blood sugar levels, combining it with other blood sugar-lowering herbal products could lead to hypoglycemia (excessively low blood sugar).
Glucomannan swells up when it absorbs the fluids in the mouth, throat, stomach, and intestines. If a person has an abnormal GI tract, there is a rare risk that glucomannan can block the throat, stomach, or intestines. Those with a GI condition that changes the shape of the stomach or intestines, or who have had GI surgery in the past, should exercise caution.
Pediatric patients, patients receiving dietary modification, and patients with impaired glucose metabolism did not benefit from glucomannan to the same degree as the overall study population in the Sood et al. meta-analysis.
Health conditions that Glucomannan may help support.
Glucomannan has been tested specifically for abdominal pain in children with functional GI disorders in a double-blind RCT (Horvath et al. 2013, World J Gastroenterol). Improved stool regularity and reduced bloating have been reported as secondary outcomes in IBS and constipation trials. However, glucomannan also commonly causes transient bloating, gas, and cramping as side effects during adaptation.
Konjac glucomannan hydrolysates (GMH) have been studied as a topical spray formulation for acne vulgaris in a human trial (Bateni et al. 2013, American Journal of Dermatology and Venereology). A 5% GMH spray applied to 26 female volunteers with active acne showed significant improvement in acne severity index at 20 and 40 days. In vitro, GMH in combination with probiotics significantly inhibited Propionibacterium acnes growth.
Glucomannan is a highly viscous soluble fiber from konjac that forms a large gel in the stomach, slowing gastric emptying and promoting satiety. Multiple RCTs and a systematic review confirm its appetite-suppressing and satiety-enhancing properties. EFSA has recognized glucomannan's contribution to weight management when taken before meals with water.
Evidence for glucomannan's effect on blood pressure is mixed. The Sood 2008 meta-analysis of 14 RCTs found no significant effect on blood pressure overall. However, the Vuksan et al. 1999 RCT in high-risk T2DM patients recorded a significant 6.9% reduction in systolic blood pressure with konjac-mannan fiber versus wheat bran placebo.
Multiple RCTs and meta-analyses demonstrate that glucomannan significantly lowers fasting blood glucose and postprandial glucose. A 2023 PMC meta-analysis of 6 RCTs (n=440 T2DM patients) found significant reductions in FBG (MD β1.08 mmol/L), 2-hour postprandial glucose, and fasting insulin. The primary mechanism is the formation of a highly viscous gel in the GI tract that slows gastric emptying and carbohydrate absorption.
Glucomannan has robust evidence from multiple meta-analyses for lowering total cholesterol, LDL cholesterol, and triglycerides. The Sood 2008 meta-analysis (14 RCTs, n=531) found WMDs of β19.28 mg/dL for total cholesterol and β15.99 mg/dL for LDL. A 2024 BMC Cardiovascular Disorders GRADE-assessed meta-analysis confirmed significant reductions. The mechanism involves bile acid sequestration in the intestine, forcing the liver to synthesize new bile acids from circulating cholesterol.
Glucomannan (from konjac root) is a viscous soluble fiber that expands in the colon, adding significant bulk to stool, softening feces, and accelerating transit. Multiple clinical RCTs confirm its efficacy as a laxative for constipation. Recognized by EFSA for its contribution to normal bowel function.
Glucomannan (from Konjac) is a soluble dietary fiber with evidence from multiple RCTs for constipation. A 2017 systematic review and meta-analysis (PMID 28429913; 3 RCTs) found glucomannan significantly increased defecation frequency in constipated children (MD=1.40/week, p=0.008). An Iranian RCT in 64 constipated pregnant women confirmed significant symptom improvement vs. control. EFSA recognizes glucomannan for normal bowel function.
Glucomannan's gel-forming and water-absorbing properties can add bulk to loose stools and slow transit, potentially reducing diarrhea severity. Konjac glucomannan hydrolysates have been studied in patients with IBD-related diarrhea, and IBS trials have reported improvements in both constipation and diarrhea subtypes.
Glucomannan (konjac fiber) is a highly viscous soluble dietary fiber positioned within the high-fiber dietary approach recommended for diverticular disease by major gastroenterological guidelines. As a bulk-forming and fermentable fiber, it reduces intraluminal colonic pressure, promotes beneficial microbiota, and contributes to SCFA production supporting colonocyte health.
Glucomannan (konjac) is a highly viscous soluble fiber that promotes satiety and has been studied in RCTs for its effects on GLP-1, weight loss, and glycemic control. A 2024 RCT found combined glucomannan/psyllium/inulin significantly reduced body weight and fat mass in obese adults.
Glucomannan (konjac glucomannan) is a highly viscous soluble fiber from konjac root that exhibits prebiotic properties by supporting gut microbiome diversity and SCFA production. Human RCTs confirm it increases butyrate-producing bacteria and Bifidobacterium, and it is recognized among dietary fibers with gut microbiota-modulating activity.
Glucomannan, a highly viscous soluble fiber from konjac root, absorbs water in the stomach to form a gel, slowing gastric emptying and promoting satiety. An 8-week double-blind RCT in 20 obese subjects found a mean weight loss of 5.5 lbs with 3 g/day versus placebo. A 2025 systematic review of RCTs found KGM supplementation (β₯5 g/day, β₯12 weeks) associated with mean reductions of 3.18 kg body weight and 1.49 kg/mΒ² BMI.
Glucomannan's documented reductions in LDL cholesterol, total cholesterol, triglycerides, and fasting blood glucose collectively address major cardiovascular risk factors. One controlled metabolic trial in T2DM patients also showed a 6.9% reduction in systolic blood pressure. These lipid and glycemic effects are considered indirectly cardioprotective.
Clinical trials have investigated glucomannan for IBS-related symptoms including abdominal pain, bloating, constipation, and diarrhea. A double-blind RCT (Horvath et al. 2013, World J Gastroenterol, n=children with abdominal pain-related FGIDs) assessed glucomannan at 2.52 g/day vs. placebo, evaluating pain and bowel outcomes. A study by Al-Ghazzewi explored konjac glucomannan hydrolysates in IBD-spectrum patients including IBS.
Glucomannan reduces postprandial insulin surges and has been shown to lower HOMA-IR in clinical trials in T2DM patients. By slowing gastric emptying and carbohydrate absorption, it attenuates insulin demand, and the resulting lower chronic hyperinsulinemia may improve peripheral insulin sensitivity over time.
A published clinical study (Chearskul et al. 2008, Diabetes Research and Clinical Practice) examined immediate and long-term effects of glucomannan on total ghrelin and leptin in type 2 diabetic patients, finding that glucomannan enhanced prandial ghrelin reduction and impeded the rise of fasting ghrelin after 4-week supplementation. This provides direct human evidence for modulation of appetite-regulating hormones.
Glucomannan addresses several components of metabolic syndrome simultaneously β elevated fasting glucose, dyslipidemia (high LDL, high triglycerides), and body weight β as confirmed in meta-analyses and RCTs. A controlled metabolic trial (Vuksan 2000, Diabetes Care) in subjects with insulin resistance syndrome showed significant improvements in multiple MetS-related markers.
Glucomannan, a highly viscous soluble fiber from Amorphophallus konjac, has robust clinical evidence supporting its role in metabolic regulation. Multiple RCTs and meta-analyses demonstrate significant reductions in fasting blood glucose, LDL cholesterol, total cholesterol, and triglycerides, alongside modest weight loss. Its primary mechanism involves gel formation in the GI tract, slowing gastric emptying and blunting postprandial glucose and insulin responses. Evidence is strongest in adults with dyslipidemia, overweight/obesity, or type 2 diabetes.
Glucomannan (konjac fiber) is a water-soluble dietary fiber that reduces postprandial glucose, insulin, and cholesterol. Multiple clinical trials confirm its insulin-sensitizing effects relevant to PCOS. Systematic reviews of PCOS supplements include dietary fiber interventions showing metabolic benefits.
Glucomannan, a viscous soluble fiber from Konjac root, has been shown in a meta-analysis of 14 RCTs (n=531 patients) to significantly reduce LDL-C and triglycerides. Unlike other soluble fibers, its TG-lowering is particularly notable, attributed to its high viscosity and modulation of hepatic lipoprotein metabolism.
Body systems that Glucomannan may help support.
Go back