Have 
you ever had a poo that looks way too big to come out of a sensible, tidy person like yourself? The bulk of the Monster Poo is related to the amount of fibre and water you consume. Picture the engorged appearance of your favourite legume after soaking it overnight in a bowl of water! A similar reaction takes place in your gut where soluble fibre and water combine to form a swollen mass of turd.
Excerpted from What’s Your Poo Telling You by Josh Richman and Anish Sheth, M.D.