This hard to understand definition is put forth by the organization, AAFCO (look on your food bag) that “ensures” pet food is balanced to meet a minimum nutrition level: purified, mechanically disintegrated cellulose prepared by processing alpha cellulose obtained as pulp from fibrous plant material.
Let’s put it in English: wood shavings or wood pulp. Yummy – not really. We pay for that.
Anyway, here’s what the Wall Street Journal says about it, and some of the not so awesome places wood shavings shows up in our human food.