Chitosan is produced commercially by deacetylation of chitin , which is the structural element in the exoskeleton of crustaceans (crabs, shrimp, etc.). Chitin is a polysaccharide found in the exoskeletons of shellfish and crustaceans. It is a unique dietary fiber that is indigestible, so it does not contribute to the amount of ingested carbohydrates. While various fibers perform this function, Chitosan seems to be the most effective. Recent research has started to uncover other roles for Chitosan as a healthful supplement, specifically for weight-loss and to help keep cholesterol levels in normal range. Chitosan is promoted as a remedy for obesity in the United States and other countries. While some studies have found that Chitosan significantly reduces weight in obese people, it is unclear whether the supplement itself, the low-calorie diet, or a combination of both led to the weight loss. More studies are needed to determine if Chitosan is a safe and effective treatment for obesity.
Chitosan is a 100% natural and acts as a super fiber. Thus, supplementing the diet with Chitosan, is part of creating a cleansing process which is said to be extremely vital to weight loss. It may have hypocholesterolemic activity in some and may be beneficial in renal disease in some. It is, at the pH of the gastrointestinal tract, a positively charged polymer and can bind to negatively charged substances. It is believed that Chitosan, similar to cholestryamine, has bile acid sequestration activity and that this may be the mechanism for its hypocholesterolemic effect. There is some evidence that Chitosan binds to bile acids and some evidence that the polymer affects the metabolism of intestinal bile acids. However, in contrast to cholestyramine, chitosan does not have consistent hypocholesterolemic activity. There is also evidence that Chitosan binds to fats in the intestine, blocking their absorption.
References:
University of Maryland Mecial Center. http://www.umm.edu/altmed/articles/obesity-000117.htm
PDR Health. http://www.pdrhealth.com/drug_info/nmdrugprofiles/nutsupdrugs/chi_0067.shtml
http://www.vanderbilt.edu/AnS/psychology/health_psychology/chitosan.htm
