Nutritional Compound



Chitosan may be the most hyped supplement at the moment. Touted as a miracle weight-loss agent, chitosan theoretically acts like a “fat sponge,” absorbing fats before they can be stored. (You don’t want to know what your body does with the fat then!) While it has been shown to reduce levels of blood fats, it doesn’t appear to help much when it comes to fat loss.

Other names for Chitosan


Where to find Chitosan

Chitosan is made from shells of crustaceans, such as crab, shrimp, and lobsters. Minute amounts are also found in mushrooms and yeast.


Why athletes use Chitosan

Chitosan is popular with people who want a quick fix to help them drop anywhere from a few pounds to a few hundred. While it could cause side effects that would limit your activity, it may be of some use to an athlete before a high-fat meal to limit the absorption of the fat.

Ways that Chitosan can enhance Fat Loss:
  • Potentially assist in a weight-management regimen by limiting fat absorption
Ways that Chitosan can enhance Longevity:
  • Reduce total triglycerides and overall cholesterol levels


Signs of Chitosan deficiency

No deficiency conditions are known to exist.

Potential uses for Chitosan

Research indicates that Chitosan may be useful in the treatment of:

  • Herpes
  • High blood sugar
  • Obesity


More about Chitosan

Chitosan (pronounced “KITE-o-san”) has recently become a popular weight-loss supplement because of bold marketing claims targeted at those seeking to eat a “carefree” diet and not having to worry about gaining bodyfat.

This fiber-like supplement theoretically acts like a “fat magnet,” attracting three to six times its weight in fats as it passes through the digestive tract, thereby helping us avoid the accumulation of bodyfat. While on the surface it appears to be the ultimate “miracle solution” for fat loss, unfortunately, chitosan takes with it minerals and fat-soluble vitamins that are vital to our health. In essence, chitosan flushes the combination of these nutrients out of the body before they can be absorbed.

How it works

Chitosan is derived from the shells of marine animals, such as crab and shrimp — forming a fiber-like compound when created. When chitosan enters the stomach, it turns into a gelatin-like substance that attracts fat to it like a strong magnet: chitosan is positively charged, and fats are negatively charged, so they have a strong attraction to each other.

Theoretically, because fat is bound so tightly to chitosan, the fat remains with the chitosan as it travels through the digestive system and is eliminated from the body with the insoluble chitosan. And if you don’t absorb the fat or the calories from fat, you could experience greater weight loss. In other words, proponents proclaim that if you eat an occasional piece of pecan pie and take some chitosan with it, the chitosan may absorb the fat and flush it right out of your body. (Needless to say, you will, however, still get the calories from all the sugar in that pie.)

In a similar manner, chitosan appears to bind to cholesterol and triglycerides in the body and may help lower levels of these blood fats. One 2-week study demonstrated that men who used up to 6 grams a day of chitosan reduced total cholesterol by 11 points while increasing HDL levels.

In conclusion

You may be thinking that this stuff sounds too good to be true, and you may be right about that. While chitosan has been shown to attach to fat and lower levels of blood fats, it doesn’t appear to really help that much, if at all, when it comes to fat loss — at least according to the human research. In addition, it appears to leach important nutrients, like the fat-soluble vitamins and essential fatty acids, from the body. What’s more, many past users have reported that they need to do more laundry — um, well, because chitosan causes (how do I put this?) “butt leakage.” The choice is yours, but many people have found better alternatives to this new, “hot,” fat reducer.



Studies show three to six grams per day to be most effective.


Chitosan should be taken no more than one hour before a meal, with at least eight ounces of water. (Because chitosan is a fiber-like product, drinking plenty of water throughout the day, at least eight glasses, may help prevent constipation.)

Consumer Beware

Because chitosan hinders the absorption of minerals and fat-soluble vitamins, experts recommend supplementing with minerals, fat-soluble vitamins (like A, D, E, and K — as found in high-potency multivitamin/mineral formulas), and essential fatty acids (such as flaxseed oil) at least three hours before taking chitosan to ensure proper vitamin/mineral intake/absorption.

Synergists of Chitosan

Vitamin C, taken with chitosan, appears to help “activate” chitosan in the body;100 mg to 200 mg of Vitamin C is typically recommended.

Safety of Chitosan

Chitosan use is recommended only occasionally, for no more than three to four weeks at a time, or with an occasional high-fat, high-calorie meal because chitosan attaches itself to essential fatty acids, minerals, and fat-soluble vitamins. Robbing your body of these vital nutrients could lead to deficiencies.

Do not use if you are allergic to shellfish.

If you are pregnant or lactating, chitosan is not recommended.

Chitosan may cause stomachaches, diarrhea, and/or inability to control bowel movements. If so, discontinue use.

Drugs that interact with Chitosan

Chitosan may reduce the absorption of some pharmaceutical medications.

Toxicity of Chitosan

No known toxicity.

Bans and restrictions

None reported.


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