Why does your body not digest corn?

Why can't the human body digest corn kernels?

• Answer:

  This is because the outside of the kernels consists of Cellulose. Cellulose monomers (β-glucose) are linked together through ß1→4 glycosidic bonds by condensation. This is in contrast to the α 1->4 glycosidic bonds present in other carbohydrates like starch. In fact, the ability to breakdown cellulose is possessed only by certain bacteria like cellulomonas etc which are often the flora on the gut walls of rumminants like cows. Cellulose is not digestible by humans, and is often referred to as 'dietary fiber' or 'roughage'. We can only digest α-glycosidic bonds. The inside of the kernel is therefore able to be digested and the outside consisting of Cellulose is not.