Chitosan comes from the hard outer skeleton of shellfish such as crab, lobster, and shrimp. It’s a complex carbohydrate that moves through the intestines without being digested or absorbed.
Chitosan has the ability to attract and bind substances from its surrounding environment. Consequently, water treatment facilities use chitosan to remove impurities and heavy metals from water.
Many supplement companies believe chitosan blocks fat absorption and use it in weight loss pills. Additionally, chitosan is used in wine to prevent spoiling, in bandages to stop bleeding, and in medications for high cholesterol and anemia.
Research shows chitosan is a highly-viscous dietary fiber as well.
Chitosan is most commonly used to promote weight loss by blocking fat absorption.
Supposedly, chitosan binds to dietary fat as it passes through the stomach and intestines. This inhibits fat absorption, which prevents fat gain and leads to fat loss. However, research on chitosan’s weight loss abilities is not conclusive.
According to an analysis of 15 studies, chitosan was proven to bind fat and enhance fat loss in poorly-designed studies. On the other hand, studies proving chitosan has minimal effects on fat were well-designed.
Additional analyses of more than 40 clinical studies also concluded there is little evidence to prove chitosan reduces body fat.
In 2004, the FDA issued a warning letter telling companies to stop making unfounded claims about chitosan’s benefits. The companies who fell under fire claimed chitosan binds to fat and stops its absorption.
Since chitosan is not associated with toxicity or dangerous side effects, it is safe for most people. However, chitosan is derived from shellfish and may be dangerous for those with shellfish allergies.
According to research, chitosan may cause the following side effects:
- Mild upset stomach
In addition, chitosan may reduce absorption of essential nutrients including calcium and vitamins A, D, E, K, and B12. This could cause health problems in the long run. Consult a doctor if you plan to use chitosan for an extended time period.
During cholesterol reduction and weight loss studies, participants consumed anywhere from 240 mg to 15,000 mg chitosan daily. The most commonly used dosage was 3,700 mg a day.
Studies involving chitosan generally lasted 4 to 24 weeks. During this time, chitosan was demonstrated to be safe. However, researchers don’t know what the long-term effects are.
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