Cumulaxative

A food or other substance that will make you shit your pants if you eat enough of it over the years. There's no way to reverse the effect. It can also sometimes be fatal

Jim "Did you hear about Craig? He ate too much kiwi and shit his pants and died"

Steve "The fuck? How could someone eat that much kiwi at once?"

Jim "Not at once, dumbass. Kiwi is a cumulaxative"