Highest Quality Supplements Since 1980

Life Extension Magazine

Block Absorption of Killer Carbohydrates

February 2010

By Julius Goepp, MD

Seaweed Extracts

Extracts from several seaweed species (actually the complex algae known as kelp) are potent inhibitors of amylase and another digestive enzyme called alpha-glucosidase. They have proven to be cost-effective means of preventing the progression of diabetes in pre-clinical models.41 In particular, extracts of Fucus vesiculosus and Ascophyllum nodosum are known to help lower blood glucose in normal and diabetic animals.42,43

A recent detailed study of a seaweed compound containing extracts from both Fucus and Ascophyllum offers insights into their mechanisms and benefits. The combination was given to laboratory rats prior to a meal with a high glycemic index.44 Such meals typically produce a rapid rise in both glucose and insulin levels in the blood, with an equally rapid drop within 60 minutes. The glucose spike contributes to excessive formation of dangerous advanced glycation end-products (AGEs). The insulin spike contributes to paradoxically low blood sugar at about 90 minutes, which can create a sensation of hunger, prompting excess food consumption.

The seaweed combination cut postprandial sugar spikes by 90% compared with untreated animals.44 That in turn reduced the insulin spike by 40%, which completely eliminated the period of low blood sugar that followed the meal in untreated rats.

In response to this seaweed combination, postprandial glucose and insulin profiles were modified to levels resembling meals with a much lower glycemic load. Blood sugar rose more slowly, achieved a shorter and more modest peak level, and then declined more gradually without ever “bottoming out” at an abnormally low level.

A recently completed human clinical trial produced similarly promising results. In this randomized, crossover, placebo-controlled, double-blind study conducted at Laval University, 23 healthy volunteers consumed 500 mg of a Fucus-Ascophyllum combination along with a high-glycemic index meal of white bread. The seaweed combination produced a 44% reduction in the glycemic response that normally follows ingestion of such a meal. The seaweed combination also produced a 22% reduction in the initial insulin production following the meal, and an overall 5.9% reduction in the area under the curve of the insulin response. The study results will be presented at the Experimental Biology meeting in Anaheim in April, 2010.45

The findings suggest that in humans, the Fucus-Ascophyllum compound may lead to earlier satiety, longer intervals between meals, fewer urges to snack, and lower total calorie intake.

Green Tea Extract

Raising basal metabolic rate is another effective mechanism for offsetting excess carbohydrate intake. Green tea extract boosts the “resting” metabolism by inhibiting an enzyme called catechol-O-methyl transferase or COMT that breaks down noradrenaline, an adrenaline-like hormone that sustains energy production.55 The resulting higher levels of metabolic activity help to burn off excess calories.56

In a large clinical trial, a patented green tea phytosome extract produced exceptional weight loss in obese individuals. Supplemented subjects lost almost 31 lbs over 3 months, while controls lost just 11 pounds!57 Both groups followed a low calorie diet. Multiple studies of overweight and obese adults indicate that green tea extracts can reduce abdominal fat as well as total cholesterol, LDL, and fasting triglyceride levels.58,59

Green tea provides another benefit in helping to alleviate the metabolic burden imposed by excess calorie ingestion. It has been shown to inhibit the lipase digestive enzyme that breaks down dietary fats for absorption into the blood.60


Roughly 1 in 5 Americans are pre-diabetic, a result of excess calorie consumption and normal aging. Sucrase, amylase, and glucosidase are digestive enzymes that break down carbohydrates, and lipase is a digestive enzyme that breaks down fat, facilitating absorption of excess calories into the blood.

As humans age, the impact of chronic caloric overload enabled by these digestive enzymes can lead to an array of life-threatening conditions ranging from high blood sugar and insulin to type 2 diabetes, obesity, and metabolic syndrome.

Natural compounds have been shown to effectively inhibit these digestive enzymes and impede the absorption of excess carbohydrate. L-arabinose neutralizes sucrase, reducing uptake of sugar (as sucrose) into the blood. Extracts of white bean, Irvingia gabonensis, and certain seaweeds block amylase and glucosidase activity, further reducing the number of ingested carbohydrate calories that are absorbed. Green or black tea extract can help reduce the activity of lipase, a digestive enzyme that helps break down fat in the gastrointestinal tract.

These natural compounds have been shown to effectively lower excess calorie absorption while reducing postprandial (post-meal) blood sugar and blood fat (triglyceride) spikes.

If you have any questions on the scientific content of this article, please call a Life Extension® Health Advisor at 1-866-864-3027.


1. Available at: http://diabetes.niddk.nih.gov/DM/PUBS/statistics/#youngpeople. Accessed November 30, 2009.

2. Bischoff H. Pharmacology of alpha-glucosidase inhibition. Eur J Clin Invest. 1994 Aug;24 Suppl 3:3-10.

3. Erkkola M, Kronberg-Kippila C, Kyttala P, et al. Sucrose in the diet of 3-year-old Finnish children: sources, determinants and impact on food and nutrient intake. Br J Nutr. 2009 Apr;101(8):1209-17.

4. Ruottinen S, Niinikoski H, Lagstrom H, et al. High sucrose intake is associated with poor quality of diet and growth between 13 months and 9 years of age: the special Turku Coronary Risk Factor Intervention Project. Pediatrics.2008 Jun;121(6):e1676-85.

5. Vorster HH, van Tonder E, Kotze JP, Walker AR. Effects of graded sucrose additions on taste preference, acceptability, glycemic index, and insulin response to butter beans. Am J Clin Nutr. 1987 Mar;45(3):575-9.

6. Ludwig DS, Majzoub JA, Al-Zahrani A, Dallal GE, Blanco I, Roberts SB. High glycemic index foods, overeating, and obesity. Pediatrics.1999 Mar;103(3):E26.

7. Van Wymelbeke V, Beridot-Therond ME, de La Gueronniere V, Fantino M. Influence of repeated consumption of beverages containing sucrose or intense sweeteners on food intake. Eur J Clin Nutr. 2004 Jan;58(1):154-61.

8. Striegel-Moore RH, Thompson D, Affenito SG, et al. Correlates of beverage intake in adolescent girls: the National Heart, Lung, and Blood Institute Growth and Health Study. J Pediatr. 2006 Feb;148(2):183-7.

9. Palmer JR, Boggs DA, Krishnan S, Hu FB, Singer M, Rosenberg L. Sugar-sweetened beverages and incidence of type 2 diabetes mellitus in African American women. Arch Intern Med. 2008 Jul 28;168(14):1487-92.

10. Culling KS, Neil HA, Gilbert M, Frayn KN. Effects of short-term low- and high-carbohydrate diets on postprandial metabolism in non-diabetic and diabetic subjects. Nutr Metab Cardiovasc Dis. 2009 Jun;19(5):345-51.

11. Seri K, Sanai K, Matsuo N, Kawakubo K, Xue C, Inoue S. L-arabinose selectively inhibits intestinal sucrase in an uncompetitive manner and suppresses glycemic response after sucrose ingestion in animals. Metabolism. 1996 Nov;45(11):1368-74.

12. Osaki S, Kimura T, Sugimoto T, Hizukuri S, Iritani N. L-arabinose feeding prevents increases due to dietary sucrose in lipogenic enzymes and triacylglycerol levels in rats. J Nutr. 2001 Mar;131(3):796-9.

13. Preuss HG, Echard B, Bagchi D, Stohs S. Inhibition by natural dietary substances of gastrointestinal absorption of starch and sucrose in rats and pigs: 1. Acute studies. Int J Med Sci. 2007;4(4):196-202.

14. Preuss HG, Echard B, Bagchi D, Stohs S. Inhibition by natural dietary substances of gastrointestinal absorption of starch and sucrose in rats 2. Subchronic studies. Int J Med Sci. 2007;4(4):209-15.

15. Terpilowska S, Zaporowska H. The role of chromium in cell biology and medicine. Przegl Lek. 2004;61 Suppl 3:51-4.

16. Broadhurst CL, Domenico P. Clinical studies on chromium picolinate supplementation in diabetes mellitus—a review. Diabetes Technol Ther. Dec 2006 Dec;8(6):677-87.

17. Balk EM, Tatsioni A, Lichtenstein AH, Lau J, Pittas AG. Effect of chromium supplementation on glucose metabolism and lipids: a systematic review of randomized controlled trials. Diabetes Care. 2007 Aug;30(8):2154-63.

18. Mosca M, Boniglia C, Carratu B, Giammarioli S, Nera V, Sanzini E. Determination of alpha-amylase inhibitor activity of phaseolamin from kidney bean (Phaseolus vulgaris) in dietary supplements by HPAEC-PAD. Anal Chim Acta. 2008 Jun 9;617(1-2):192-5.

19. Obiro WC, Zhang T, Jiang B. The nutraceutical role of the Phaseolus vulgaris alpha-amylase inhibitor. Br J Nutr. 2008 Jul;100(1):1-12.

20. Layer P, Zinsmeister AR, DiMagno EP. Effects of decreasing intraluminal amylase activity on starch digestion and postprandial gastrointestinal function in humans. Gastroenterology.1986 Jul;91(1):41-8.

21. Santoro LG, Grant G, Pusztai A. Effects of short-term feeding of rats with a highly purified phaseolin preparation. Plant Foods Hum Nutr. 1997;51(1):61-70.

22. Pusztai A, Grant G, Buchan WC, Bardocz S, de Carvalho AF, Ewen SW. Lipid accumulation in obese Zucker rats is reduced by inclusion of raw kidney bean (Phaseolus vulgaris) in the diet.

Br J Nutr. 1998 Feb;79(2):213-21.

23. Tormo MA, Gil-Exojo I, Romero de Tejada A, Campillo JE. White bean amylase inhibitor administered orally reduces glycaemia in type 2 diabetic rats. Br J Nutr. 2006 Sep;96(3):539-44.

24. Fantini N, Cabras C, Lobina C, et al. Reducing effect of a Phaseolus vulgaris dry extract on food intake, body weight, and glycemia in rats. J Agric Food Chem. 2009 Oct 14;57(19):9316-23.

25. Udani JK, Singh BB, Barrett ML, Preuss HG. Lowering the glycemic index of white bread using a white bean extract. Nutr J. 2009;8:52.

26. Udani J, Hardy M, Madsen DC. Blocking carbohydrate absorption and weight loss: a clinical trial using Phase 2 brand proprietary fractionated white bean extract. Altern Med Rev. 2004 Mar;9(1):63-9.

27. Celleno L, Tolaini MV, D’Amore A, Perricone NV, Preuss HG. A Dietary supplement containing standardized Phaseolus vulgaris extract influences body composition of overweight men and women. Int J Med Sci. 2007;4(1):45-52.

28. Udani J, Singh BB. Blocking carbohydrate absorption and weight loss: a clinical trial using a proprietary fractionated white bean extract. Altern Ther Health Med. 2007 Jul-Aug;13(4):32-7.

29. Chokshi D. Toxicity studies of Blockal, a dietary supplement containing Phase 2 Starch Neutralizer (Phase 2), a standardized extract of the common white kidney bean (Phaseolus vulgaris). Int J Toxicol. 2006 Sep-Oct;25(5):361-71.

30. Deglaire A, Moughan PJ, Bos C, Tome D. Commercial Phaseolus vulgaris extract (starch stopper) increases ileal endogenous amino acid and crude protein losses in the growing rat. J Agric Food Chem. 2006 Jul 12;54(14):5197-202.

31. Omoruyi F, Adamson I. Digestive and hepatic enzymes in streptozotocin-induced diabetic rats fed supplements of dikanut (Irvingia gabonensis) and cellulose. Ann Nutr Metab. 1993;37(1):14-23.

32. Adamson I, Okafor C, Abu-Bakare A. Erythrocyte membrane ATPases in diabetes: effect of dikanut (Irvingia gabonensis). Enzyme. 1986;36(3):212-5.

33. Adamson I, Okafor C, Abu-Bakare A. A supplement of Dikanut (Irvingia gabonesis) improves treatment of type II diabetics. West Afr J Med. 1990 Apr-Jun;9(2):108-15.

34. Ngondi JL, Oben JE, Minka SR. The effect of Irvingia gabonensis seeds on body weight and blood lipids of obese subjects in Cameroon. Lipids Health Dis. 2005;4:12.

35. Oben JE, Ngondi JL, Momo CN, Agbor GA, Sobgui CS. The use of a Cissus quadrangularis/Irvingia gabonensis combination in the management of weight loss: a double-blind placebo-controlled study. Lipids Health Dis. 2008;7:12.

36. Ngondi JL, Etoundi BC, Nyangono CB, Mbofung CM, Oben JE. IGOB131, a novel seed extract of the West African plant Irvingia gabonensis, significantly reduces body weight and improves metabolic parameters in overweight humans in a randomized double-blind placebo controlled investigation. Lipids Health Dis. 2009;8:7.

37. Oben JE, Ngondi JL, Blum K. Inhibition of Irvingia gabonensis seed extract (OB131) on adipogenesis as mediated via down regulation of the PPARgamma and leptin genes and up-regulation of the adiponectin gene. Lipids Health Dis. 2008;7:44.

38. Cetinalp-Demircan P, Bekpinar S, Gurdol F, Orhan Y. Adiponectin is a link among inflammation, insulin resistance, and high-density lipoprotein cholesterol but is not associated with paraoxonase activity in premenopausal women. J Clin Hypertens (Greenwich). 2009 Nov;11(11):672-7.

39. Fontana L, Klein S, Holloszy JO. Effects of long-term calorie restriction and endurance exercise on glucose tolerance, insulin action, and adipokine production. Age (Dordr). 2009 Nov 11.

40. Stenholm S, Koster A, Alley DE, et al. Adipocytokines and the metabolic syndrome among older persons with and without obesity - the InCHIANTI Study. Clin Endocrinol (Oxf). 2009 Oct 31.

41. Iwai K. Antidiabetic and antioxidant effects of polyphenols in brown alga Ecklonia stolonifera in genetically diabetic KK-A(y) mice. Plant Foods Hum Nutr. 2008 Dec;63(4):163-9.

42. Lamela M, Anca J, Villar R, Otero J, Calleja JM. Hypoglycemic activity of several seaweed extracts. J Ethnopharmacol. 1989 Nov;27(1-2):35-43.

43. Zhang J, Tiller C, Shen J, et al. Antidiabetic properties of polysaccharide- and polyphenolic-enriched fractions from the brown seaweed Ascophyllum nodosum. Can J Physiol Pharmacol. 2007 Nov;85(11):1116-23.

44. InnoVactiv, Inc. Data on file.

45. Available at: http://www.naturalproductsinsider.com/news/2009/12/insea2-reduces-glycemic-response.aspx#. Accessed December 2, 2009.

46. Stulc T, Cecka R. Lipid-lowering treatment in metabolic syndrome. Vnitr Lek. 2009 Jul-Aug;55(7-8):626-30.

47. Andel M, Polák J, Kraml P, Dlouhý P, Stich V. Chronic mild inflammation links obesity, metabolic syndrome, atherosclerosis and diabetes. Vnitr Lek. 2009 Jul-Aug;55(7-8):659-65.

48. Hano T, Nishio I. Treatment of hypertension in the patients with obesity. Nippon Rinsho. 2001 May;59(5):973-7.

49. Kopf D, Muhlen I, Kroning G, Sendzik I, Huschke B, Lehnert H. Insulin sensitivity and sodium excretion in normotensive off- spring and hypertensive patients. Metabolism. 2001 Aug;50(8):929-35.

50. Noda M, Matsuo T, Nagano-Tsuge H, et al. Involvement of angiotensin II in progression of renal injury in rats with genetic non- insulin-dependent diabetes mellitus (Wistar fatty rats). Jpn J Pharmacol. 2001 Apr;85(4):416-22.

51. Hegele RA. Premature atherosclerosis associated with monogenic insulin resistance. Circulation. 2001 May 8;103(18):2225-9.

52. Katz AS, Goff DC, Feldman SR. Acanthosis nigricans in obese patients: Presentations and implications for prevention of atherosclerotic vascular disease. Dermatol Online J. 2000 Sep;6(1):1.

53. Kaaks R. Plasma insulin, IGF-I and breast cancer. Gynecol Obstet Fertil. 2001 Mar;29(3):185-91.

54. Nilsen TI, Vatten LJ. Prospective study of colorectal cancer risk and physical activity, diabetes, blood glucose and BMI: exploring the hyperinsulinaemia hypothesis. Br J Cancer. 2001 Feb 2;84(3):417-22.

55. Dulloo AG, Seydoux J, Girardier L, Chantre P, Vandermander J. Green tea and thermogenesis: interactions between catechin-polyphenols, caffeine and sympathetic activity. Int J Obes Relat Metab Disord. 2000 Feb;24(2):252-8.

56. Diepvens K, Westerterp K R, Westerterp-Plantenga MS. Obesity and thermogenesis related to the consumption of caffeine, ephedrine, capsaicin, and green tea. Am J Physiol Regul Integr Comp Physiol. 2007 Jan;292(1):R77-85.

57. Di Pierro F, Menghi AB, Barreca A, Lucarelli M, Calandrelli A. Greenselect Phytosome as an adjunct to a low-calorie diet for treatment of obesity: a clinical trial. Altern Med Rev. 2009 Jun;14(2):154-60.

58. Maki KC, Reeves MS, Farmer M, et al. Green tea catechin consumption enhances exercise-induced abdominal fat loss in overweight and obese adults. J Nutr. 2009 Feb;139(2):264-70.

59. Tsai CH, Chiu WC, Yang NC, Ouyang CM, Yen YH. A novel green tea meal replacement formula for weight loss among obese individuals: a randomized controlled clinica J Nutr Biochem. 2000 Jan;11(1):45-51.

60. Juhel C, Armand M, Pafumi Y, Rosier C, Vandermander J, Lairon D. Green tea extract (AR25) inhibits lipolysis of triglycerides in gastric and duodenal medium in vitro. Int J Food Sci Nutr. 2009 Sep 7:1-9.