Literature on Mannan and the Glucose Response

Glycemic and lipid responses to glucomannan in Thais with type 2 diabetes mellitus.

J Med Assoc Thai. 2007 Oct;90(10):2150-7.Chearskul S, Sangurai S, Nitiyanant W, Kriengsinyos W, Kooptiwut S, Harindhanavudhi T.
Department of Physiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand. sisch@mahidol.ac.th

Abstract

OBJECTIVE: To evaluate the benefits of glucomannan supplement on glycemic and lipid controls in type 2 diabetic patients. MATERIAL AND METHOD: A single-blind, placebo-controlled, crossover trial with two treatments separated by a 2-week washout period was performed in 10 men and 10 women with type 2 diabetes mellitus. Two separated protocols of experiments were sequentially followed. Initially, purified glucomannan (1 g) or placebo was ingested 30 min before 75-g glucose load to evaluate their effects on glucose absorption and insulin secretion in oral glucose tolerance test (OGTT). Later, the glycemic and lipid changes after 4-week intervention with 3 g/day glucomannan comparing to the placebo were determined. The standard OGTT was performed before and after ending of each intervention. RESULTS: Glucomannan taken before performing the OGTT can lower the rise of blood glucose and insulin from 1 to 2 hour in comparison with the placebo, though a statistically significance of insulin was not achieved. Long-term glucomannan supplement significantly reduced the 120-min glucose area under the curve of OGTT. Glucomannan also decreased the rise of low-density lipoprotein cholesterol (LDL-C). Reductions of HOMA-insulin resistance index and body mass index were detected in glucomannan-treated group though the former was shown only in females. No within- and between-group differences of insulin, fructosamine, and other lipids were observed in glucomannan- nor placebo- treated groups. CONCLUSION: In type 2 diabetes, pre-prandial glucomannan ingestion attenuated a rise of blood glucose without significantly affecting insulin levels. Long-term supplement of glucomannan to the regular diabetic regimen lessened post challenge glucose AUC and impeded the rise of LDL-C. Supplement of glucomannan may be beneficial to the glycemic and lipid controls in type 2 diabetes mellitus.

PMID: 18041436 [PubMed - indexed for MEDLINE]

Dietary fibres, fibre analogues, and glucose tolerance: importance of viscosity.

1978 May 27;1(6124):1392-4. Jenkins Et al.,
Jenkins DJ, Wolever TM, Leeds AR, Gassull MA, Haisman P, Dilawari J, Goff DV, Metz GL, Alberti KG. Br Med J.

To define the type of dietary fiber of fiber analogue with the greatest potential use in diabetic treatment, groups of four to six volunteers underwent 50-g glucose tolerance tests (GTT) with and without the addition of either guar, pectin, gum tragacanth, methylcellulose, wheat bran, or cholestyramine equivalent to 12 g fiber. The addition of each substance significantly reduced blood glucose concentration at one or more points during the GTT and generally reduced serum insulin concentrations. The greatest flattening of the glucose response was seen with guar, but this effect was abolished when hydrolysed non-viscous guar was used. The reduction in the mean peak rise in blood glucose concentration for each substance correlated positively with its viscosity (r = 0.926; P less than 0.01), as did delay in mouth-to-caecum transit time (r = 0.885; P less than 0.02). Viscous types of dietary fiber are therefore most likely to be therapeutically useful in modifying postprandial hyperglycaemia.

Publication Types:

• Clinical Trial
• Randomized Controlled Trial

PMID: 647304 [PubMed - indexed for MEDLINE]

 

Hydrolyzed guar gum decreases postprandial blood glucose and glucose absorption in the rat small intestine.

Takahashi T, Yokawa T, Ishihara N, Okubo T, Chu DC, Nishigaki E, Kawada Y, Kato M, Raj Juneja L.

Faculty of Human Life Science, Mimasaka University, Tsuyama, Okayama 708 8511, Japan. takahashitoru71@nifty.com

Abstract

We hypothesized that infusing partially hydrolyzed guar gum (PHGG) into the duodenum would reduce increases in postprandial plasma glucose by decreasing the rate of glucose diffusion from the small intestine luminal digesta of the rat. The postprandial plasma glucose and apparent glucose disappearance from the small intestine were measured after infusing artificial digesta containing 0 (control), 3.0, or 6.0 g/L PHGG into the duodenum via a cannula under anesthesia in experiments 1 and 2. The diffusion of glucose in the artificial digesta was estimated using dialysis tubing, filled with the same artificial digesta, soaked in a buffer in experiment 3. In experiment 1, the plasma glucose concentration was lower in the digesta containing 3.0 and 6.0 g/L PHGG than in the control digesta at 120 minutes (P < .05). The plasma insulin concentration was lower for the digesta containing 6.0 g/L PHGG than for the control digesta at 60 minutes (P < .05) and lower for the digesta containing 6.0 g/L PHGG than for that containing 3.0 g/L PHGG at 120 minutes (P < .05).The area under the curve of plasma glucose and insulin (experiment 1), apparent disappearance of glucose in the lumen of the small intestine (experiment 2), and net disappearance of glucose in the dialysis tube depended negatively on the viscosity of the artificial digesta (P < .05, .05, .001, and .05), which was increased by adding PHGG. Therefore, PHGG can decrease the postprandial blood glucose by lowering the rate of absorption from the small intestine in the rat by reducing the diffusion of glucose in the lumen.

PMID: 19628109 [PubMed - indexed for MEDLINE]

New sources of dietary fibre.

Int J Obes. 1987;11 Suppl 1:57-65
Madar Z.

Two sources of dietary fibre were discussed in this presentation: soybean and fenugreek. Soybean dietary fibre (SDF) was found to be effective in reducing plasma glucose levels in diabetic and fa/fa rats, ob/ob mice and in non-insulin dependent diabetes mellitus (NIDDM) subjects. Supplementation of SDF in bread was more effective in glucose reduction than powder. SDF was also found to be more effective in subjects with fasting blood glucose levels above 7.2 mmol/l. SDF had no effect on insulin levels in rats or NIDDM subjects although the insulin levels in ob/ob mice were lower after 180 d feeding. SDF had no effect on body weight or lipid levels in rats and human subjects. However, in diabetic rats with high levels of blood cholesterol, SDF feeding decreased the cholesterol levels after 45 d SDF administration. Addition of powdered fenugreek to an oral glucose tolerance test significantly reduced the subsequent postprandial blood glucose level in diabetic rats. Inclusion of fenugreek to the meal tolerance test given to NIDDM also decreased the postprandial blood glucose levels. Fenugreek was found to reduce the rate of gastric emptying and to inhibit glucose transport, indicating the blood modulating effect of fenugreek to be due mainly to delayed gastric emptying with direct interference with intestinal glucose absorption. Soybean and fenugreek dietary fibres reveal a potential benefit for the control of glucose metabolism in diabetes with additional advantages resulting from their ease in usage either in a mixture of water or milk products or in cooking.

Publication Types:

• Review

PMID: 3032826 [PubMed - indexed for MEDLINE]

Guar gum: a miracle therapy for hypercholesterolemia, hyperglycemia and obesity. 

Crit Rev Food Sci Nutr. 2007;47(4):389-96.Butt MS, Shahzadi N, Sharif MK, Nasir M. Institute of Food Science and Technology, University of Agriculture, Faisalabad 38040, Pakistan.

Abstract

The number of hypercholesterolemic and hyperglycemic people is increasing rapidly in the world. The prevention against these health problems is related to a complex management of conventional and non-conventional risk factors. The inclusion of dietary fiber in the diet is the right approach to reduce these risks. Cholesterol and glucose lowering effects are most often associated with gelling, mucilaginous, and viscous fibers such as guar gum, an edible thickening agent. It has widespread applications in the food industry due to its ability to hydrate without heating. The demand for guar gum is still growing rapidly because in addition to its indispensable role in lowering serum cholesterol and glucose levels, it is also considered helpful in weight loss programs. The main thrust of therapeutic and medicinal properties lies in the soluble dietary fiber content of guar gum to improve the serum biochemical profile of human and non-human primates, reducing total serum cholesterol, triglycerides, increasing the high density lipoprotein cholesterol level, and the management of glycemic indices and obesity. Among the various intervention strategies, diet diversification is the right approach to overcome these problems. Composite flours containing wheat and legumes have proven practical uses and are being utilized in many parts of the world to improve the nutritional and functional properties of flour. The main focus of this manuscript is to review the available information on various aspects of guar gum with special reference to its effectiveness in reducing the cardiovascular disease risk, diabetes and weight loss programs.

PMID: 17457723 [PubMed - indexed for MEDLINE]

Effect of Trigonella foenum-graecum (fenugreek) seeds on glycaemic control and insulin resistance in type 2 diabetes mellitus: a double blind placebo controlled study.

J Assoc Physicians India. 2001 Nov;49:1057-61. Comment in:
Gupta A, Gupta R, Lal B.
Jaipur Diabetes and Research Centre.

OBJECTIVES: To evaluate the effects of Trigonella foenum-graecum (fenugreek) seeds on glycemic control and insulin resistance, determined by HOMA model, in mild to moderate type 2 diabetes mellitus we performed a double blind placebo controlled study. METHODS: Twenty five newly diagnosed patients with type 2 diabetes (fasting glucose < 200 mg/dl) were randomly divided into two groups. Group I (n=12) received 1 gm/day hydroalcoholic extract of fenugreek seeds and Group II (n=13) received usual care (dietary control, exercise) and placebo capsules for two months. RESULTS: At baseline both the groups were similar in anthropometric and clinical variables. Oral glucose tolerance test, lipid levels, fasting C-peptide, glycosylated haemoglobin, and HOMA-model insulin resistance were also similar at baseline. In group 1 as compared to group 2 at the end of two months, fasting blood glucose (148.3 +/- 44.1 to 119.9 +/- 25 vs. 137.5 +/- 41.1 to 113.0 +/- 36.0) and two hour postglucose blood glucose (210.6 +/- 79.0 to 181.1 +/- 69 vs. 219.9 +/- 41.0 to 241.6 +/- 43) were not different. But area under curve (AUC) of blood glucose (2375 +/- 574 vs 27597 +/- 274) as well as insulin (2492 +/- 2536 vs. 5631 +/- 2428) was significantly lower (p < 0.001). HOMA model derived insulin resistance showed a decrease in percent beta-cell secretion in group 1 as compared to group 2 (86.3 +/- 32 vs. 70.1 +/- 52) and increase in percent insulin sensitivity (112.9 +/- 67 vs 92.2 +/- 57) (p < 0.05). Serum triglycerides decreased and HDL cholesterol increased significantly in group 1 as compared to group 2 (p < 0.05). CONCLUSIONS: Adjunct use of fenugreek seeds improves glycemic control and decreases insulin resistance in mild type-2 diabetic patients. There is also a favourable effect on hypertriglyceridemia.

Publication Types:

• Clinical Trial
• Comparative Study
• Randomized Controlled Trial

PMID: 11868855 [PubMed - indexed for MEDLINE]

Effects of Locust Bean Gum on Glucose Tolerance, Sugar Digestion, and Gastric Motility in Rats

ALAN C. TSAI ANDBECKY PENG
Human Nutrition Program, School of Public Health,
University of Michigan, Ann Arbor, MI 48109

ABSTRACT

Effects of selected indigestible gel-forming complex carbohydrates, including locust bean gum, guar gum, and pectin, on glucose tolerance and food motility were studied in rats. Addition of 2.5% of guar gum or locust bean gum to an oral glucose tolerance test solution significantly altered the postprandial serum glucose response. Although all three complex carbohydrates tested did not reduce the initial rise in serum glucose, locust bean gum and guar gum significantly reduced its subsequent rebound hypoglycemia. Further tests with locust bean gum showed that these effects were dependent on the concentration of the gum added to the test solution or diet. Addition of locust bean gum to test diets reduced the rate of gastric emptying and thus slowed down the passage of food from the stomach into the upper small intestine. The study suggests that addition of locust bean gum to the diet can flatten the post prandial serum glucose curve by slowing the rate of food passage from the stomach into the small intestine. It is probable that locust bean gum and other similar materials may be useful as an adjunct dietary treatment of diabetes mellitus in humans. J. Nutr. Ill: 2152-2156, 1981.

Immediate and long-term effects of glucomannan on total ghrelin and leptin in type 2 diabetes mellitus. 

Diabetes Res Clin Pract. 2009 Feb;83(2):e40-2. Epub 2008 Dec 23.Chearskul S, Kriengsinyos W, Kooptiwut S, Sangurai S, Onreabroi S, Churintaraphan M, Semprasert N, Nitiyanant W.Department of Physiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand. sisch@mahidol.ac.th

Abstract

Effects of glucomannan as a supplementary treatment in type 2 diabetes mellitus were investigated by measuring ghrelin, leptin and insulin responses to OGTT. Glucomannan enhanced prandial ghrelin reduction when given before glucose load and impeded the rise of fasting ghrelin after 4-week supplement. Ghrelin-induced feeding may be attenuated by glucomannan.

PMID: 19108925 [PubMed - indexed for MEDLINE]