Cellulose gum is a common thickening agent made from the cell wall of plants and wood used in many modern foods. The substance is found in a variety of food products, ranging from breads to dairy items. Food manufacturers like it for its texture, protein stabilization and moisture retention.
The Food and Drug Administration has permitted the use of cellulose gum in foods for about 50 years. The FDA classifies the non-toxic substance as fiber. While cellulose gum is found in many packaged foods, it is also commonly used in foods labeled "organic" as well. Typically the addition of cellulose gum makes a product lower in fat and higher in fiber than it would otherwise be, as it often replaces trans fats and bleached white flour.
In addition to working as a thickening agent, cellulose gum prevents ice crystals from forming on ice cream that has been frozen, removed from the freezer and then frozen again. It also stabilizes foam in many beers and helps items, such as yogurt, in which ingredients tend to separate hold together. Human beings are not able to digest cellulose. As a result, the substance passes through the digestive tract without being absorbed into the bloodstream.