If stomach acid can break down metal, why doesn't corn digest?

Question

If stomach acid can break down metal, why doesn't corn digest?

Answer 1

It passes through too quickly.  If you ate metal it won't break down unless it was somehow left in the juices for a long long time.  Things digested in your stomach are only there for a number of hours.

Answer 2

The outer layer of corn kernels contain complex carbohydrates, like cellulose which our digestive track is unable to digest. The inside of the corn kernel contains mostly starch, which we are able to digest easily. So if you were to chew each kernel into a mushy paste, you wouldn't see them in your stool.

There was an interesting BBC documentary series by Dr Alice Roberts called "Don't Die Young", series 2 discusses the stomach and intestines where they looked at this in greater detail. A short preview is available on youtube - http://www.youtube.com/watch?v=ZKrQog1Us...

Answer 3

Who said stomach acid can break down metal?