Cholesterol Reduction by Chitosan ϩ Glucomannan
would favor bile acid binding, with subsequent micelle disrup-
tion and decreased cholesterol solubilization, as the mechanism
of cholesterol lowering in the present study. However, gluco-
mannan is a highly viscous dietary fiber and increasing intes-
tinal contents viscosity decreases cholesterol absorption [41]. It
would thus appear that a higher dietary concentration of chi-
tosan is required to decrease fat digestibility than to achieve
cholesterol lowering.
Hasegawa Y: A novel use of chitosan as a hypocholesterolemic
agent in rats. Am J Clin Nutr 33:787–793, 1980.
12. LeHoux J-G, Grondin F: Some effects of chitosan on liver function
in the rat. Endocrinology 132:1078–1084, 1993.
13. Razdan A, Pettersson D: Effect of chitin and chitosan on nutrient
digestibility and plasma lipid concentrations in broiler chickens.
Br J Nutr 72:277–288, 1994.
14. Maezaki Y, Tsuji K, Nakagawa Y, Kawai Y, Akimoto M: Hypo-
cholesterolemic effect of chitosan in adult males. Biosci Biotech
Biochem 57:1439–1444, 1993.
15. Fukada Y, Kimura K, Ayaki Y: Effect of chitosan feeding on
intestinal bile acid metabolism in rats. Lipids 26:395–399, 1991.
16. Gallaher CM, Munion J, Hesslink Jr R, Wise J, Gallaher DD:
Cholesterol reduction by glucomannan and chitosan is mediated by
changes in cholesterol absorption and bile acid and fat excretion in
rats. J Nutr 130:2753–2759, 2000.
CONCLUSIONS
The present study confirms the hypocholesterolemic effect
of a chitosan ϩ glucomannan supplement reported in rats [16]
and extends the finding to humans. The trend toward increased
steroid excretion with supplement consumption suggests this is
the primary mechanism for the effect. The failure to increase
fecal fat excretion and the lack of change in body weight after
28 days of consumption of the supplement suggests that, at the
dose used, this supplement would likely not be effective in
accelerating weight loss.
17. Sciutto AM, Colombo P: Lipid-lowering effect of chitosan dietary
integrator and hypocaloric diet in obese subjects. Acta Toxicol
Ther 16:215–230, 1995.
18. Veneroni G, Veneroni F, Contos S, Tripodi S, De Bernardi M,
Guarino C, Marletta M: Effect of a new chitosan dietary integrator
and hypocaloric diet on hyperlipidemia and overweight in obese
patients. Acta Toxicol Ther 17:53–70, 1996.
19. Locket PL, Gallaher DD: An improved procedure for bile acid
isolation and purification and tissue distribution in the rat. Lipids
24:221–223, 1989.
REFERENCES
20. Sheltawy MJ, Lowowsky MS: Determination of fecal bile acids by
an enzymatic method. Clin Chim Acta 64:127–132, 1975.
21. Schneider CL, Cowles RL, Stuefer-Powell CL, Carr TP: Dietary
stearic acid reduces cholesterol absorption and increases endoge-
nous cholesterol excretion in hamsters fed cereal-based diets. J
Nutr 130:1232–1238, 2000.
1. Manson JE, Tosteson H, Ridker PM, Satterfield S, Hebert P,
O’Connor GT, Buring JE, Hennekens CH: The primary prevention
of myocardial infarction. N Engl J Med 326:1406–1416, 1992.
2. Anderson JW, Deakins DA, Floore TL, Smith BM, Whitis SE:
Dietary fiber and coronary heart disease. Crit Rev Food Sci Nutr
29:95–147, 1990.
22. Pittler MH, Abbot NC, Harkness EF, Ernst E: Randomized, dou-
ble-blind trial of chitosan for body weight reduction. Eur J Clin
Nutr 53:379–381, 1999.
3. Topping DL: Dietary fibre and cholesterol metabolism. Curr Opin
Lipidol 2:20–31, 1991.
23. Wuolijoki E, Hirvela¨ T, Ylitalo P: Decrease in serum LDL cho-
lesterol with microcrystalline chitosan. Methods Find Exp Clin
Pharmacol 21:357–361, 1999.
4. Marlett JA: Sites and mechanisms for the hypocholesterolemic
actions of soluble dietary fiber sources. Adv Exp Med Biol 427:
109–121, 1997.
24. Brown L, Rosner B, Willett WW, Sacks FM: Cholesterol-lowering
effects of dietary fiber: a meta-analysis. Am J Clin Nutr 69:30–42,
1999.
5. Shimizu H, Yamauchi M, Kuramoto T, Kubota N, Matsuda M,
Hoshita T: Effects of dietary Konjac mannan on serum and liver
cholesterol levels and biliary bile acid composition in hamsters.
J Pharmacobio-Dyn 14:371–375, 1991.
25. Jansen S, Lopez-Miranda J, Salas J, Castro P, Paniagua J, Lopez-
Segura F, Ordovas J, Jimenez-Pereperez J, Blanco A, Perez-
Jimenez F: Plasma lipid response to hypolipidemic diets in young
healthy non-obese men varies with body mass index. J Nutr 128:
1144–1149, 1998.
6. Yun-Hua H, Li-Shi Z, Hong-Ming Z, Rui-Shu W, Yin-Zhu Z:
Influences of refined konjac meal on the levels of tissue lipids and
the absorption of four minerals in rats. Biomed Environ Sci 3:306–
314, 1990.
26. Bronsgeest-Schoute DC, Hermus RJJ, Dallinga-Thie GM, Haut-
vast JG: Dependence of the effects of dietary cholesterol and
experimental conditions on serum lipids in man. III. The effect on
serum cholesterol of removal of eggs from the diet of free-living
habitually egg-eating people. Am J Clin Nutr 32:2193–2197, 1979.
27. Muls E, Van Gaal LV, Autier P, Vansant G: Effects of initial BMI
and on-treatment weight change on the lipid-lowering efficacy of
fibrates. Int J Obes 21:155–158, 1997.
7. Walsh DE, Yaghoubian V, Behforooz A: Effect of glucomannan
on obese patients: A clinical study. Int J Obesity 8:289–93, 1984.
8. Arvill A, Bodin L: Effect of short-term ingestion of konjac gluco-
mannan on serum cholesterol in healthy men. Am J Clin Nutr
61:585–589, 1995.
9. Furda I: Aminopolysaccharides—their potential as dietary fiber. In
Furda I (ed): “Unconventional Sources of Dietary Fiber.” ACS
Symposium Series: 214:105–122, 1983.
28. Cole TG, Bowen PE, Schmeisser D, Prewitt TE, Aye P, Langen-
berg P, Dolecek TA, Brace LD, Kamath S: Differential reduction
of plasma cholesterol by the American Heart Association Phase 3
Diet in moderately hypercholesterolemic, premenopausal women
10. Sugano M, Fujikawa T, Hiratsuji Y, Hasegawa Y: Hypocholester-
olemic effects of chitosan in cholesterol-fed rats. Nutr Rep Int
18:531–537, 1978.
11. Sugano M, Fujikawa Y, Hiratsuji K, Nakashima N, Fukuda N,
432
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