Chitin Vs. Chitosan

Chitin and chitosan sound remarkably similar for a reason -- chitosan is made from chitin. Chitosan is used in weight-loss supplements and agriculture, whereas the uses for chitin are much more diverse. If you are considering using a weight loss aid with chitosan, consult a healthcare provider first.

Identification

Chitin is a cellulose-type material that makes up the exoskeleton, or shell, of anthropods such as crabs, insects and scorpions. It is among the most abundant organic compounds in nature, along with cellulose and starch. Chitin is a polysaccharide that can be processed into many derivatives, such as chitosan.

Chitin Uses

Chitin has wound-healing properties and is used in sutures, skin dressings and skin-donor graft sites. It's also found in contact lenses, artificial blood vessels and household products, such as sponges, diapers and tampons, and cosmetics, such as make-up powder, nail polish and moisturizers. It's used for water filtration and cleaning up toxic compounds like PCBs. Chitin also is added to animal feed mixes that contain whey because it helps animals digest the whey. In agriculture, chitin added to soil helps control parasites and contributes to nutrient retention in the soil.

Chitosan Uses

Chitosan is a processed form or chitin that is more water soluble than chitin. It's made by heating chitin with a chemical solution. Chitosan is used in dietary supplements for its fat-binding properties. Similar to some plant fibers, chitosan is not digestible. When the fat you consume binds to chitosan in your digestive tract, it can help reduce the amount of fat your body absorbs. Theoretically, this will lead to weight loss. Chitosan also is used in agriculture. Seeds that are treated with chitosan are more disease-resistant, according to the University of Delaware College of Marine and Earth Studies. Chitosan also causes favorable changes in plant metabolism, which leads to increased germination and better crop yields, according to "Monomers, Polymers and Composites from Renewable Resources," by Mohamed Naceur Belgacem and Alessandro Gandini.

Weight-Loss Claims

While claims about chitosan's weight loss prowess abound on the Internet, science doesn't always show such a benefit. A 1999 "European Journal of Clinical Nutrition" study concludes that using chitosan without altering your diet does not result in weight loss. A 2008 "Cochrane Database of Systematic Reviews" report notes that the many trials on chitosan for weight loss have produce variable results and that many of these trials are of poor quality. Trials that are well-designed indicate that chitosan has at best minimal benefits for weight loss, according to lead review author A.B. Jull.