Which type of carbohydrate is the body unable to digest, but is still important for lowering cholesterol, balances glucose levels, and helps prevent overeating.

Cellulose

Explanation:

Cellulose is the carbohydrate which is unable to be digested by body. Adding fiber's (cellulose)  to one's diet reduces blood cholesterol level because soluble fiber  dissolves in water to form a gel, which moves slowly through the intestines binding up fat, dietary cholesterol, bile salts, and sugar to be excreted. Once excreted, these are no longer available to build more cholesterol. Also cellulose remains undigested but is effectively making one gain more calories, so it helps prevents over eating.