What does Chitosan do?
dietary fiber, chitosan is not digestible but may have beneficial effects
on the gastrointestinal tract. Chitosan may reduce the absorption of bile acids
or cholesterol, either of which may cause a lowering of blood cholesterol.1 This effect has been repeatedly
demonstrated in animals, and a preliminary human study showed that 36 grams
per day of chitosan taken for two weeks resulted in a 6% drop in cholesterol and
a 10% increase in HDL (the good) cholesterol.2 Another preliminary study showed a
43% lowering of total cholesterol in people being treated for kidney failure
with dialysis who took 4 grams per day of chitosan for twelve weeks. This group
also appeared to have improved kidney function and less severe anemia after
Chitosan in large amounts given with vitamin C has been shown to reduce
dietary fat absorption in animals fed a high-fat diet.4 5
6 Unfortunately, mineral and
fat-soluble vitamin absorption is also reduced by feeding animals large amounts
of chitosan.7 No studies have been done on the
effects of chitosan on dietary fat absorption in humans.
Animal and preliminary human research suggests that chitosan may prevent the
blood pressure-elevating effects of a high-salt meal, possibly by reducing the
absorption of chloride. A small study showed that men taking 5 grams of chitosan
with a meal resulted in no elevation in blood pressure, while the
same meal without chitosan significantly elevated systolic blood pressure.8
Chitosan may also have an effect on bacteria in the intestines. A small human
study found that taking 36 grams per day of chitosan for two weeks reduced
indicators of putrefaction in the intestines,9 a change that might help prevent
diseases, such as colon cancer.10
Where is it found?
Chitosan is a supplement commonly extracted from the
shells of crustaceans, such as shrimp and crab.
Chitosan has been used in connection with the following conditions
(refer to the individual health concern for complete information):
Click Here For The Best New Chitosan Fat Blocker
Who is likely to be deficient? Chitosan is not an essential nutrient, so
deficiencies do not occur.
How much is usually taken? Most human research has used 36
grams per day with meals.
any side effects or interactions? While no long-term studies of the effects
of chitosan on human health have been done, animal studies suggest that harmful
effects on mineral and fat-soluble vitamin absorption, on maintenance of normal
intestinal flora, and on normal growth in children and during pregnancy are
possible.11 People with intestinal malabsorption
syndromes should not use chitosan. At the time of writing, there were no well-known drug interactions with
1. Koide SS. Chitin-chitosan:
properties, benefits and risks. Nutr Res 1998;18:1091101 [review].
2. Maezaki Y, Tsuji K, Nakagawa Y, et al. Hypocholesterolemic effect of chitosan
in adult males. Biosci Biotech Biochem 1993;57:143944.
3. Jing SB, Li L, Ji D, et al. Effect of chitosan on renal function in patients
with chronic renal failure. J Pharm Pharmacol 1997;49:72123.
4. Deuchi K, Kanauchi O, Imasato Y, et al. Effect of the viscosity or
deacetylation degree of chitosan on fecal fat excreted from rats fed on a
high-fat diet. Biosci Biotech Biochem 1995;59:78185.
5. Deuchi K, Kanauchi O, Imasato Y, et al. Decreasing effect of chitosan on the
apparent fat digestibility by rats fed on a high-fat diet. Biosci Biotech
6. Kanauchi O, Deuchi K, Imasato Y, et al. Increasing effect of a chitosan and
ascorbic acid mixture on fecal dietary fat excretion. Biosci Biotech Biochem
7. Deuchi K, Kanauchi O, Shizukuishi M, et al. Continuous and massive intake of
chitosan affects mineral and fat-soluble vitamin status in rats fed on a
high-fat diet. Biosci Biotech Biochem 1995;59:121116.
8. Kato H, Taguchi T, Okuda H, et al. Antihypertensive effect of chitosan in
rats and humans. J Trad Medicinen 1994;11:198205.
9. Terada A, Hara H, Sato D, et al. Effect of dietary chitosan on faecal
microbiota and faecal metabolites of humans. Microb Ecol Health Dis
10. Bone E, Tamm A, Hill M. The production of urinary phenols by gut bacteria
and their possible role in the causation of large bowel cancer. Am J Clin
11. Koide SS. Chitin-chitosan: properties, benefits and risks. Nutr Res