Twice as much as this: 
You didnt give me much to start with..what did Elvis’s colon weigh?
Twice as much as this:
My favorite shock jocks Don & Mike were obsessed with it. They bandied about this figure of 40 pounds.
I assume it was highly exaggerated but I do know that “megacolon” is common in opiate abusers as a side effect of the drugs is the suppression of the peristalysis that moves the poo through the system.