Chitosan has the unique ability to dissolve and bind to fats and cholesterol in the stomach. Because Chitosan is mostly indigestible, it can then prevent these lipids from being absorbed in the digestive tract. This can ultimately promote safe weight-loss and a reduction in cholesterol levels.
Scientists have intensively investigated the properties and uses of chitin, chitosan, and their derivatives – collectively they are the subjects of approximately 1,000 scientific studies and hundreds of patents.
Chitin (pronounced kite-in) and chitosan (kite-o-san) are fibers derived from marine animals. Chitin is a polysaccharide-a string of sugar molecules-that are derived from sources like crab, lobster and shrimp shells, and marine coral, that are not eaten as foods. Chitin is chemically similar to cellulose and starch, the abundant plant fibers. It is used to make various other substances, including chitosan, which is derived from chitin by heating it with a chemical solution.
There are no significant sources of chitin from other food sources.
Chitosan's primary mechanism of action is well-established. It is known to differ from other polysaccharides in that it has a strong positive charge that lets it chemically bond with certain compounds, especially fats and cholesterol. Other mechanisms of action in the body are still being investigated. The ability to bond with fats and other substances is also the reason for many of chitin and chitosan's industrial uses. For example, spread on water chitin absorbs grease and other potentially toxic substances, which is why it is prominent in wastewater treatment processes.
Chitosan has the advantage of being more soluble in water than chitin.
Chitin and chitosan are also now being taken like acidophilus, FOS, and other supplements to speed the transit of foods through the digestive system and to promote the growth of beneficial live bacteria in the intestines.
Weight loss was the most dramatic result from a Helsinki Chitosan clinical pilot study. The subjects lost an average of 8% of their body weight in a 4 week period. [ARS Medicina, Helsinki, Aug-Oct, 1994]
To prevent intestinal blockage, chitin and chitosan should always be taken with plenty of water. Also, these supplements can bind with essential fatty acids, fat-based vitamins, such as vitamins A, D, E, and certain drugs, thus reducing these substances' absorption and effectiveness. Chitin and chitosan should be taken separately from EFA supplements and vitamins, and before a high-fat or high-calorie meal.
The optimum dose is 1500 to 3000mg half an hour before a meal. Ascorbic acid (not buffered) seems to enhance its effects. Calorie restriction, especially fats, would have the same weight loss effect without the added cost.
Chitin and chitosan are nontoxic and free of side-effects, although they share the same precautions for safe use that apply to other types of fiber.
Check with your doctor if you are taking any fat-soluble medication. Although chitin and chitosan are considered non-allergenic, people with shellfish allergies should not take them, nor should pregnant or breastfeeding women.
In a study of patients with chronic renal failure undergoing long-term hemodialysis 450mg of chitosan 3 times a day for 12 weeks produced multiple benefits. Mean serum cholesterol went down 43% and mean serum hemoglobin increased from 5.8 to 6.8 g/dl in those patients who received the chitosan. Mean urea (from 75 to 45 mM) and creatinine (from 1. 001 to 0.875 mM) levels in serum showed significant reductions after 12 weeks of chitosan treatment. Compared with the control group, the treatment group reported significantly improved appetite, sleep and feeling of physical strength. No significant side effects were seen. (Jing SB. et al. J Pharm Pharmacol 1997;49:72 1-723.)