CHITOSAN

Revolutionizing Weight Loss?

Jamie Fritch

 

 

 
 

Just What They Want To Hear

    Everyone enjoys a good fatty meal from McDonald's, KFC, or any other fast food restaurant from time to time.  Or maybe just a bag of chips, a candy bar, or an ice cream cone.  All of these are food items which people consume on a regular basis and are full of fat.  For years, the public has worried about the intake of fat from items such as these and has almost obsessed over weight, figures, and fat.  With all the hype about liquid diets, diet pills, diet programs, etc. who wouldn't jump at the idea of an all natural solution.  The makers of this product has certainly done their share of work to create an image truly appealing to any and all that dream of losing that extra fat.  This probable solution is called chitosan and is simply a fat inhibitor which appears to work miracles for those in search of a safe way to lose that body fat.  The information surrounding this product is extremely impressive and appears to justify a revolutionary new discovery.  However, is this truly what it is dressed up to be or is it yet another gimmick?
 
Chitosan: Where did it come from?
 
    Regardless of chitosan's miraculous overview, it is a very simple substance which has been around for ages.  It is taken from chitin, a polysaccharide found in the exoskeletons of crustaceans.  It is processed by removing the shells from shellfish such as shrimp, lobster, and crabs.  The shells are then ground into a pulverous powder.  This powder is then deacetylated, or basically stripped of specific chemical groups which allows the compound to thus actively "soak up fats."  Or so this is what the producers claim.  It has been used in the past in the process of detoxifying water.  It was simply spread over the surface of water, where it would immediately absorb any toxic substances such as greases, oils, or dangerous heavy metals.  The process is so complete that a scum forms over the surface of water and is then easily removed.  For this reason, chitosan is extremely popular all over the world in water purification plants.  The present form of chitosan has just been introduced recently as a weight loss supplement. (Chitosan: The Fiberand Fat Buster)

How It Works

    Let's now take a look at exactly what is chitosan and how it is used for weight loss.  The allegations of how chitosan works are as follows.  However, note that there is no significant studies to thus back up this information or to explain exactly how such procedures take place. Basically stated, chitosan is a special fiber which is able to "soak up" or absorb anywhere from six to ten times its weight in fat and oils.  In substance, it is chemically similar to the plant fiber, cellulose. However, chitosan is able to significantly bind with fat molecules and convert them into a form which the human body does not absorb. (Revolutionary Discovery: Chitosan)  It claims to affect the fat prior to it reaching the stomach and thus the fat never has a chance to be metabolized.  It prevents the absorption and storage of fat by converting into a gel which "traps" the fat.  In some sort, it creates a "grease ball" from this excess fat, which is too large to be absorbed by the body.  It thus becomes an inert substance and is excreted in the stool. (Absorption of Fats)  Chitosan fiber is unlike other fibers in that it carries a positive ionic charge.  Since lipids, fats, and bile acids all possess negative charges, there is a chemical bond between the two and thus they attract naturally to one another. (Fat Magnet)  This unique ability is what makes chitosan so remarkable.  This amazingly "too good to be true" ability is also what causes suspicions to arise on the validity of these claims.  .

Benefiting Weight Loss
 
    Besides from the obvious effect that fat is not absorbed into the body with the presence of chitosan, it goes a lot deeper in benefiting weight loss.  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. Take note that these are again the simple declarations made by the producers of chitosan and are supported with no background studies or thus medical proof of any sort.  Another stated advantage of chitosan comes from the idea that the chitosan-bound fat leaves the intestinal tract without ever entering the bloodstream.  Exactly how this process takes place is not clear and seems to be somewhat far fetched.  If this indeed is possible, then the point is made that there would be no caloric value and no matter how much chitosan a person takes, the caloric count remains zero. (Revolutionary Discovery: Chitosan)  The producers of chitosan-based products also try to claim that since a person taking chitosan continues to eat some sort of fats and is able to continue eating these types of food, the body does not crave such fattening foods nor is it starving or feeling any added sense of hunger.  By supplementing chitosan into one's diet, there is less fat that the body accumulates.  With less fat entering the body, the body turns to previously stored body fat to burn up.  This shifts the energy source from your diet to your stored body fat and results in a net reduction in that fat - and in your weight. (Fat Zapper)   Obviously, the allegations are extremely pleasing, now whether or not they actually could be a reality is another side to these claims.

Additions to Increase Effects
 
    The benefits of chitosan in weight loss can be greatly boosted by the simple additions to go along with the chitosan supplements.  First, M.D. Labs have followed current research and clinical studies and have determined that by adding Vitamin C, one can enhance the absorption of lipids.  The producers claim that increased appetite suppression is obtained by the addition of citric acid, which boosts the swelling action of chitosan.  They claim that this addition could so much as double the effectiveness of chitosan. (Your Health Store - Chitosan)  Thus, many of the products on the market today which contain chitosan as a chief substance, also include the addition of some sort of vitamin C supplement.  One such product is the Fat Zapper, which contains 250 mg of chitosan, 240 mg of high quality grapefruit fiber, and 10 mg of vitamin C per capsule.

Administering Chitosan

  The instructions in which to properly administer the supplementation of chitosan are quite simple.  The most common advice is to follow some sort of simple plan such as the one that follows:  Take one or two capsules ten minutes before each of your three daily meals.  Here the chitosan will supposedly help bind excess fat from the meal or snack which has just been consumed.  It also serves as an added fiber intake, which aides in digestion, soothing the stomach lining and speeding up the process of elimination of undigested fats and wastes.  Also, drink about six to eight glasses of water daily.  This is common in any situation where there is an addition of fiber or a need for faster digestion.  Also, it is extremely advisable to include moderate exercise.  (Fat Zapper)  Simple exercises which contain any type of sustained aerobic activity can greatly enhance the results and the time in which physical results will appear.  These steps are fairly easy and create a setting in which one's body, with the added chitosan, can actively work to reduce the amount of body fat.

Other Claims to Fame

    There are many other benefits which chitosan claims to have other than weight loss.  It also inhibits LDL cholesterol and boosts HDL cholesterol.  It promotes the healing of ulcers and lesions, helps to control blood pressure, reduces blood levels of uric acid, helps prevent constipation, acts as an antacid, helps prevent irritable bowel syndrome, enhances calcium to strengthen bones, inhibits plaque/tooth decay, and offers anti-tumor action.  (Nutrient That Binds Fat)  All of these benefits are obviously significant within themselves.  However, note that there is not specific research to accompany these claims or any hard data which would classify their validity.  Weight loss is claimed to be the greatest effect of chitosan on the body and thus is where it seeks most of its alleged fame.

Specific Research Studies

    Specific studies which tested the effects of chitosan as a weight loss supplement on humans were near to impossible to find.  One study which apparently tested the effects of chitosan to the hypocholesterolaemic response of human subjects was published in 1993 by a group of Japanese doctors.  However, any copy of this report was not available and only references from this report were made.  The only other true scientific study that was done was on the effects on broiler chickens to chitosans of different viscosity.  In this prospective cohort study setup, broiler chickens were fed ad libitum on a control diet based on maize and maize starch diets containing low-, medium-, or high-viscosity chitosans at a level of 15 g/kg.  The diets began of the total 224 broiler chickens on the second day of their lives.  The groups were randomly allocated and divided into separate cages of mixed sex.  The cages contained raised wire floors in a windowless, light- and temperature-controlled room.  The birds all had free access to water and feed for the duration of the experiment.  Both were monitored specifically to observe if either was consumed more or less with the addition of chitosan to the diet.  After the 22 day experiment, many conclusions were drawn.  The 22 days consisted of regular check-ups including body weight testing, blood plasma tests, and feed intake records.  Feeding the high-viscosity-chitosan-containing diets reduced ileal fat digestibility by 8% on average.  However, increasing the viscosity of the chitosan fraction could not be correlated specifically with the increases in terminal ileal digesta viscosity.  Therefore, it could not be established that any necessary increases in chitosan are necessary to receive the few benefits accredited directly to the fiber itself.  Significant reductions in body weight, feed intake and plasma control concentrations were observed. (Razdan & Pettersson, 1994)

Discussion on Chitosan from Researchers

    With the unavailability of specific research studies to support the claims made on chitosan as a revolutionary weight loss supplements, one must be careful on what is fact and what is speculation.  The following are conclusions and specific discussion made from researchers, although take note that their specific studies were not given with precise accounts of their experimentation.  It is now generally accepted that soluble dietary fibers increase gastrointestinal lumen viscosity (Edwards, 1990) and delay gastric emptying (Chang, 1983).  Chitosans have specifically been shown to alter bile acid composition, increase neutral sterol excretion and reduce ileal fat digestibility (Fukada, 1991; Maezaki, 1993; Razdan & Pettersson, 1994).  The mechanisms by which chitosans achieve these effects are not fully established, although increased intestinal viscosity and increased bile acid-binding capacity are two proposals currently favored (Furda, 1990).  Since polyglucosamines are the second-most-ubiquitous dietary fiber after cellulose, it is reasonable to assume that much more research regarding the nutritional significance of these important dietary fibers is to be expected (Knorr, 1991).  Chitosan has such characteristics that are associated with a dietary fiber which are assumed to be related to the reductions in cholesterol as well as increases in the excretion of neutral steroids observed in animal experiments (Furda, 1990; Ikeda, 1993; Razdan & Pettersson, 1994).  Chitosan, which is largely deacetylated, contains cationic groups located on the polyglucosamine chain (Sugano, 1993).  Thus, chitosan may have a bile acid-binding capacity, causing entrapment or disintegration of mixed micelles in the duodenum and ileum (Furda, 1990).  This interruption in bile acid circulation would lead to reduced lipid absorption and increased sterol excretion.  Chitosan is relatively insoluble in water but is soluble in dilute acids, giving rise to highly-viscous dietary fibers (Furda, 1990).  It has been suggested that viscous dietary fibers such as chitosan inhibit uptake of dietary lipids by increasing the thickness of the intestinal lumen boundary layer, a proposal again supported by numerous animal experiments (Sugano, 1993; Ikeda, 1993).

Conclusions
 
     As far as one can see, chitosan appears to be virtually too good to be true.  There are no known side-effects and it appears to be extremely safe. (Revolutionary Discovery:Chitosan)  However, these claims are very difficult to take seriously with such a lack of true scientific evidence.  Perhaps, now that such products are being advertised and surely the public is falling into the trap of this "miracle diet fiber," more studies will take place to test the validity to such claims as these.  As for the allegations of chitosan as this super fiber, there are no obvious hazards yet.  However, due to its composition, anyone allergic to seafood and pregnant women should not take chitosan.  Chitosan is not a drug, but a natural fiber.  It is extremely low in toxicity and safe for consumption. (All Natural Fat Gobbler)  An ARS Medicina (Helsinki) 1994 report proved that test subjects lost 8% of their body weight in four weeks using chitosan. This product has been safely used for weight loss for over two decades.  Chitosan is also a biodegradable substance as as environmentall biocompatible.  (Absorption of Fats)  Whether or not there are downfalls to the product is never overlooked, however the knowledge of any at this time is unknown.  As for now, chitosan is being used as a healthy alternative to the expensive and dangerous diet drugs on the market and is pictured as the "Holy Grail" for those carrying around a few too many pounds. (Revolutionary Discovery:Chitosan)  But, BE CAREFUL, it is easy to make claims of this magic diet solution with little or no evidence to back it up.
 
 
 
 
Bibliography
 
Chang, M.L.W. (1983) Dietary pectic: effect on metabolic processes in rats.  In Unconventional
     Sources of Dietary FiberAmerican Chemical Society Symposium Series no. 214, pp.
    143-154, Washington, DC:  American Chemical Society.

Edwards, C. (1990)  Mechanisms of action on dietary fibre on small intestinal absorption and
    motility.  In New Developments in Dietary Fiber, pp. 95-104.  New York: Plenum Press.

Fukada, Y., Kimura, K. & Ayaki, Y. (1991).  Effect of chitosan feeding on intestinal bile acid
    metabolism in rats.  Lipids 26, 395-399.

Furda, I. (1990).  Interaction of dietary fiber with lipids - mechanic theories and their limitations.  In
    New Developments in Dietary Fiber, pp. 67-82.  New York: Plenum Press.

Ikeda, I., Sugano, M., Yoshida, K., Sasaki, E., Iwamoto, Y. & Hatano, K. (1993)  Effects of
    chitosan hydrolysates on lipid absorption and on serum and liver lipid concentrations in rats.
    Journal of Agricultural and Food Chemistry 41, 431-435.

Knorr, D. (1991).  Recovery and utilisation of chitin and chitosan in food processing waste
    management.  Food Technology 45, 114-122.

Maezaki, Y., Tsuji, K., Nakagawa, Y., Kawai, & Akimoto, M. (1993).  Hypocholesterolemic
    effect of chitosan in adult males.  Bioscience, Biotechnology and Biochemistry 57, 1439-1444.

Razdan, A. & Pettersson, D. (1994).  Effect of chitin and chitosan on nutrient digestibility and
    plasma lipid concentrations in broiler chickens.  British Journal of Nutrition 72, 277-288.
 

 
 
 

 

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