What is chitosan?
Chitosan is a dietary supplement made from the shells of crabs, shrimp, and lobsters. The chitosan manufacturers claim that this supplement can help with weight loss and it is often sold as a weight loss supplement. Medical research in animals has shown that chitosan may bind to fat in food and prevent it from being absorbed into the body. But, medical research in people has not shown this effect nor proven that chitosan helps with weight loss. Chitosan has also been studied as a way to lower cholesterol. However, there is no proof that chitosan can lower cholesterol in people.
Potential chitosan side effects
Some people experience side effects such as an upset stomach, constipation, headache, or swelling of wrists and heels with chitosan. Since chitosan is made from shellfish, people with shellfish allergies should check with a physician before taking this supplement. People with shellfish allergies can have side effects from supplements made from shellfish like chitosan such as hives and swelling, to more severe allergic reactions like rapid pulse and shock. Chitosan has been used in kidney failure, although more studies need to be completed to determine its effectiveness for this use. The recommended dose of chitosan depends on the particular product. Chitosan is available in capsules and tablets and is usually taken before meals.
Drug interactions with chitosan
There is very little information available about drug interactions with chitosan but chitosan may interfere with the absorption of vitamins A, D, E, K, and beta-carotene from the stomach. To avoid this interaction, vitamin supplements should be taken at least four hours before or after taking chitosan.