There's cellulose -that is wood pulp in Wonder bread and a lot of other processed foods.
Profit is the food industry's main focus. Up to 30% savings are realized by using cellulose over other ingredients. After all, food ingredients are rising in cost. And usually cellulose adds to the shelf life.
Learn more:
http://www.naturalnews.com/033767_cellulose_food.html
Humans should not be eating this crap and supporting companies that make this sh*t..
Jim