This song was based, moore or less entirely, on “eat” idioms.
Here’s the full reveal of the idioms used in the song:
You are what you eat. To eat one’s words, to eat one’s hat.
You cannot have your cake and eat it.
Eat out of one’s hand. Eat someone’s ass out.
You have to eat a peck of dirt before you die. Variety is the spice of life.
Dog eat dog. I could eat a horse.
Eat out of house and home.
Eat your gun.
Eat it up.
Mad enough to eat nails. Eat someone alive.
Don’t crap where you eat. Eat at the Y.
Eat the bread of idleness. Eat someone’s dust.
He that would eat the kernel must first crack the nut.
Eat/live high off the hog.
Eat through something.
The cat would eat fish, but would not wet her feet.
You are (not) what you eat.