Chitosan – Does it really help with weight loss?


What is Chitosan?


It is a polysaccharide which is made from the exoskeletons of many crustaceans such as shell fish.

Sources: Krill, shrimp, prawn, crayfish, lobster, crab etc.

Function: Has a variety of commercial and biomedical usage.

Similar weight loss ingredients: Glucomannan, nopal, etc.

The carbohydrate chitosan is a derivative of chitin, the polysaccharide responsible for the hard outer skeleton of many insects and crustaceans (shell fish). It is also derived from mushrooms. Chitosan is commercially prepared by treating the outer shells of crabs, lobsters, crayfish, krill, prawns, squids and shrimps with an alkali. Normally, sodium hydroxide is used for this purpose. Chitosan has been used widely in a variety of applications ranging from commercial to biomedical uses. Some evidence also suggests the possible role of chitosan in weight loss.

Benefits of Chitosan for Weight Loss

There has been controversy in the benefits of chitosan for weight loss because of inconsistent results of research. But among the weight loss enthusiasts, chitosan is known to:

  • Naturally block the absorption of fats from diet
  • Helps in detoxifying your body
  • Improves bowel movement
  • Lower blood cholesterol

How Does It Work?

The structure of chitosan is similar to cellulose – the plant fiber. It works like fiber, but is more powerful because it can bind to the fat present in your food. Its binding to the molecules of fat prevent the absorption of fat from your digestive tract which then leads to increased fat excretion. It is said that chitosan can bind to fat molecules greater than six times its weight. This results in less fat absorption and more fat excretion which leads to weight loss.

Other Benefits


Other than the above mentioned benefits of chitosan for weight loss, there are countless other uses of chitosan as given below:

  • Fights cancer
  • Strengthens immune system
  • Used as a biopesticide and seed treatment in agriculture
  • Used in cosmetic industry
  • Used as an antibacterial agent and in wound dressings to reduce bleeding
  • Used in wine making as a fining agent
  • Used in drug delivery systems
  • Helps in the treatment of gum disease
  • Helps people with kidney failure in maintaining proper functions of the body
  • Helps in wound healing for post-op plastic surgery patients
  • It is used in water filtration

Clinical Studies


In a research conducted on an experimental model of the digestive tract, it was found that chitosan interacts with oil to inhibit its absorption from the small intestine, increasing fat excretion.

In another study (source) conducted for a period of 90 days with 96 overweight individuals, either chitosan capsules (of 500 mg were given five times a day) or a placebo was given to the participants. There was no change in the lifestyle or the calorie intake of both groups. At the end of the study, it was found that the fungal chitosan (from mushrooms) was able to reduce the mean body weight in the test group as compared to the placebo group. A mean body weight of up to 3 kg was lost in 90 days.

According to a review research study, the effects of chitosan on body weight are not very significant in high quality studies. 14 trials accounting for 1071 participants were reviewed, and their analysis revealed that chitosan has a small but significant effect of the mean body weight of the participants.

Side Effects

Because it is a natural product derived from shellfish and other living organisms, chitosan is relatively safe to use for most people when taken orally or applied to the skin. But some people may have the following side effects when ingested:

  • Gas
  • Constipation
  • Upset stomach

A word of caution

Because of lack of evidence, pregnant and breast-feeding mothers are advised to stay on the safe side by avoiding use of chitosan.

Another growing concern is regarding shellfish allergy. People who develop shellfish allergy may also be allergic to chitosan as it is made from the shells of shellfish. But it is argued that the allergy is due to the meat of shellfish rather than the shell, so chitosan may be safe to use for people with shellfish allergy as well. But the final verdict on this matter is not established yet, so make sure to consult your doctor before you decide to start on chitosan.


Research evidence suggests both the significance and insignificance of chitosan for weight loss. But when coupled with a healthy low-caloric diet and regular exercise, the consumption of chitosan can lead to probable weight loss. If you have made up your mind to start on chitosan, do consult your doctor before taking the final leap in case you have any allergies or other health conditions that you are unaware of.