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Nutritional Supplement

Glucomannan

Where to Find It

Glucomannan is a purified fiber from konjac root that is available as a bulk powder to be taken in hard-gelatin capsules or used as an ingredient in food.

How to Use It

The amount of glucomannan shown to be effective as a laxative is 3–4 grams per day.29,30 Effective amounts for lowering blood cholesterol have been 4–13 grams per day.31,32,33 For controlling blood sugar, 500–700 mg of glucomannan per 100 calories in the diet has been used successfully in controlled research.32,33 For weight loss, 1 to 3 grams before each meal has been effective.36,37 When using glucomannan and other dietary fiber supplements, it is best to start out with a small amount and increase gradually. It is recommended to drink at least 8 ounces of water each time any bulk-forming laxative, including glucomannan, is taken.

References

1. Vuksan V, Sievenpiper J, Owen R, et al. Beneficial effects of viscous dietary fiber from Konjac-mannan in subjects with the insulin resistance syndrome: results of a controlled metabolic trial. Diabetes Care 2000;23:9–14.

2. Zheng J, Li H, Zhang X, et al. Prebiotic Mannan-Oligosaccharides Augment the Hypoglycemic Effects of Metformin in Correlation with Modulating Gut Microbiota. J Agric Food Chem 2018;66:5821–31.

3. Chearskul S, Sangurai S, Nitiyanant W, et al. Glycemic and lipid responses to glucomannan in Thais with type 2 diabetes mellitus. J Med Assoc Thai 2007;90:2150–7.

4. Chearskul S, Sangurai S, Nitiyanant W, et al. Glycemic and lipid responses to glucomannan in Thais with type 2 diabetes mellitus. J Med Assoc Thai 2007;90:2150–7.

5. Yoshida M, Vanstone C, Parsons W, et al. Effect of plant sterols and glucomannan on lipids in individuals with and without type II diabetes. Eur J Clin Nutr 2006;60:529–37.

6. Chen H, Sheu W, Tai T, et al. Konjac supplement alleviated hypercholesterolemia and hyperglycemia in type 2 diabetic subjects--a randomized double-blind trial. J Am Coll Nutr 2003;22:36–42.

7. Chen H, Nie Q, Hu J, et al. Glucomannans Alleviated the Progression of Diabetic Kidney Disease by Improving Kidney Metabolic Disturbance. Mol Nutr Food Res 2019;63:e1801008.

8. Hopman WP, Houben PG, Speth PA, Lamers CB. Glucomannan prevents postprandial hypoglycaemia in patients with previous gastric surgery. Gut 1988;29:930-4.

9. Kneepkens CM, Fernandes J, Vonk RJ. Dumping syndrome in children. Diagnosis and effect of glucomannan on glucose tolerance and absorption. Acta Paediatr Scand 1988;77:279-86.

10. Behera S, Ray R. Konjac glucomannan, a promising polysaccharide of Amorphophallus konjac K. Koch in health care. Int J Biol Macromol 2016;92:942–56.

11. Devaraj R, Reddy C, Xu B. Health-promoting effects of konjac glucomannan and its practical applications: A critical review. Int J Biol Macromol 2019;126:273–81.

12. Vuksan V, Jenkins DJ, Spadafora P, et al. Konjac-mannan (glucomannan) improves glycemia and other associated risk factors for coronary heart disease in type 2 diabetes. A randomized controlled metabolic trial. Diabetes Care 1999;22:913-9.

13. Zhang MY, Huang CY, Wang X, et al. The effect of foods containing refined Konjac meal on human lipid metabolism. Biomed Environ Sci 1990;3:99-105.

14. Arvill A, Bodin L. Effect of short-term ingestion of konjac glucomannan on serum cholesterol in healthy men. Am J Clin Nutr 1995;61:585-9.

15. Walsh DE, Yaghoubian V, Behforooz A. Effect of glucomannan on obese patients: a clinical study. Int J Obes 1984;8:289-93.

16. Passaretti S, Franzoni M, Comin U, et al. Action of glucomannans on complaints in patients affected with chronic constipation: a multicentric clinical evaluation. Ital J Gastroenterol 1991;23:421-5.

17. Marzio L, Del Bianco R, Donne M, et al. Mouth-to-cecum transit time in patients affected by chronic constipation: effect of glucomannan. Am J Gastroenterol 1989;84:888-91.

18. Marsicano LJ, Berrizbeitia ML, Mondelo A. Use of glucomannan dietary fiber in changes in intestinal habit. G E N 1995;49:7-14 [in Spanish].

19. Signorelli P, Croce P, Dede A. A clinical study of the use of a combination of glucomannan with lactulose in the constipation of pregnancy. Minerva Ginecol 1996;48:577-82 [in Italian].

20. Staianno A, Simeone D, Giudice ED, et al. Effect of the dietary fiber glucomannan on chronic constipation in neurologically impaired children. J Pediatr 2000;136:41-5.

21. Papi C, Ciaco A, Koch M, Capurso L. Efficacy of rifaximin in the treatment of symptomatic diverticular disease of the colon. A multicentre double-blind placebo-controlled trial. Aliment Pharmacol Ther 1995;9:33-9.

22. Biancardi G, Palmiero L, Ghirardi PE. Glucomannan in the treatment of overweight patients with osteoarthritis. Curr Ther Res 1989;46:908-12.

23. Vita PM, Restelli A, Caspani P, Klinger R. Chronic use of glucomannan in the dietary treatment of severe obesity. Minerva Med 1992;83:135-9 [in Italian].

24. Walsh DE, Yaghoubian V, Behforooz A. Effect of glucomannan on obese patients: a clinical study. Int J Obes 1984;8:289-93.

25. Livieri C, Novazi F, Lorini R. The use of highly purified glucomannan-based fibers in childhood obesity. Pediatr Med Chir 1992;14:195-8 [in Italian].

26. Kimm SY. The role of dietary fiber in the development and treatment of childhood obesity. Pediatrics 1995;96:1010-4.

27. Livieri C, Novazi F, Lorini R. The use of highly purified glucomannan-based fibers in childhood obesity. Pediatr Med Chir 1992;14:195-8 [in Italian].

28. Vido L, Facchin P, Antonello I, et al. Childhood obesity treatment: double blinded trial on dietary fibres (glucomannan) versus placebo. Padiatr Padol 1993;28:133-6.

29. Marsicano LJ, Berrizbeitia ML, Mondelo A. Use of glucomannan dietary fiber in changes in intestinal habit. G E N 1995;49:7-14 [in Spanish].

30. Passaretti S, Franzoni M, Comin U, et al. Action of glucomannans on complaints in patients affected with chronic constipation: a multicentric clinical evaluation. Ital J Gastroenterol 1991;23:421-5.

31. Arvill A, Bodin L. Effect of short-term ingestion of konjac glucomannan on serum cholesterol in healthy men. Am J Clin Nutr 1995;61:585-9.

32. Vuksan V, Jenkins DJ, Spadafora P, et al. Konjac-mannan (glucomannan) improves glycemia and other associated risk factors for coronary heart disease in type 2 diabetes. A randomized controlled metabolic trial. Diabetes Care 1999;22:913-9.

33. Vuksan V, Sievenpiper JL, Owen R, et al. Beneficial effects of viscous dietary fiber from Konjac-mannan in subjects with the insulin resistance syndrome: results of a controlled metabolic trial. Diabetes Care 2000;23:9-14.

34. Walsh DE, Yaghoubian V, Behforooz A. Effect of glucomannan on obese patients: a clinical study. Int J Obes 1984;8:289-93.

35. Vita PM, Restelli A, Caspani P, Klinger R. Chronic use of glucomannan in the dietary treatment of severe obesity. Minerva Med 1992;83:135-9 [in Italian].

36. Henry DA, Mitchell AS, Aylward J, et al. Glucomannan and risk of oesophageal obstruction. Br Med J 1986;292:591-2.

37. Werley MS, Burleigh-Flayer H, Mount EA, Kotkoskie LA. Respiratory sensitization to konjac flour in guinea pigs. Toxicology 1997;124:115-24.

Copyright © 2020 TraceGains, Inc. All rights reserved.

Learn more about TraceGains, the company.

The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2020.

Copyright © 2020 TraceGains, Inc. All rights reserved.

The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2020.