Your digestive system is your body's Fun House, whereby food goes on a long, dark, scary ride, taking all kinds of unexpected twists and turns, being attacked by vicious secretions along the way, and not knowing until the last minute whether it will be turned into a useful body part or ejected into the Dark Hole by Mister Sphincter.
Fasting stirs a hunger in your spirit that goes deeper than the temporary you experience in your flesh.