Carrageenan (from Irish 'carraigín', "little rock") is a linear line of sulfated food additives that are extracted from red edible seaweeds. They are widely used in the food industry, for their gelling, thickening, and stabilizing properties.

Their main application is in dairy and meat products, due to their strong binding to food proteins. Carrageenan is a vegetarian and vegan alternative to gelatin in some applications or may be used to replace gelatin in confectionery.

In the U.S., carrageenan is allowed under Food and Drug Administration (FDA) regulations as a direct food additive and is considered safe when used in the amount necessary as an emulsifier, stabilizer, or thickener in foods, except those standardized foods that do not provide for such use.

The European Food Safety Authority also concluded "there is no evidence of any adverse effects in humans from exposure to food-grade carrageenan, or that exposure to degraded carrageenan from use of food-grade carrageenan is occurring".

There is some debate over whether the findings of animal- and cell-based studies can apply to people. Carrageenan has been found to cause inflammation of the gut, altering flora, and was found to be a triggering factor of inflammatory bowel diseases such as ulcerative colitis and Crohn Disease. The possible side effects of consuming carrageenan include bloating, glucose intolerance, colon cancer & food allergies.

More Info: en.wikipedia.org