Chitosan is a supplement that is derived from the exoskeletons of crustaceans like shrimp, crayfish, crabs, and other shellfish. Chitosan is marketed as a supplement for weight loss and also as a cholesterol-lowering agent. T-Squared reports that chitosan is composed of many molecules of chitin, or the exoskeleton of crustaceans, strung together. The supplement is reported to be completely indigestible and act similarly to plant fiber in your body. According to PDR Health, chitosan is reported to work as a weight loss supplement by binding fat molecules in your bowel and preventing them from being absorbed. The Memorial Sloan-Kettering Cancer Center reports that chitosan may also help to lower the level of bad cholesterol, low-density lipoproteins, in your blood (See References 1, 2 and 3).
Because chitosan is derived from the exoskeleton of shellfish, the Memorial Sloan-Kettering Cancer Center reports that people with an allergy to shellfish should not take the supplement. If you do not have a shellfish allergy, you may still develop an allergy to chitosan. Symptoms of an allergic reaction include difficulty breathing, swelling of the lips and/or tongue, chest pain, and/or hives or a skin rash. If you develop any of these symptoms while taking chitosan, stop taking the supplement and notify your doctor immediately (See References 1 and 2).
Gastrointestinal Side Effects
According to PDR Health and the Memorial Sloan-Kettering Cancer Center, gastrointestinal problems are the most common side effects associated with the use of chitosan. Nausea, vomiting, abdominal cramping, and constipation are all possible gastrointestinal side effects of taking chitosan. Some of these side effects may be dose related. If you experience any of the symptoms listed, stop taking chitosan and notify your doctor. He may recommend that you decrease the amount of supplement you are taking or that you no longer take the chitosan at all depending on the type and severity of your symptoms (See References 1 and 2).
Other Side Effects
PDR Health reports that in addition to allergic reactions and gastrointestinal problems, other side effect have been reported from the use of chitosan. Headaches and swelling of the heels and wrists are also listed as possible chitosan side effects. If you experience a persistent headache or swelling of your wrists and/or heels, stop taking chitosan and notify your doctor of your symptoms (See Reference 1).