Second, fasting tests what is in our hearts. Fasting brings to the surface that which is deep down, which maybe can mask from ourselves and others with large doses of corn chips and root beer. Fasting churns that stuff up from the depths. I can usually control that with a hamburger and fries . . . Third, fasting teaches us that we do not live by bread alone, but by every word that comes from the mouth of the Lord.
Hunger makes stark and raw our humanness, or human neediness and fragility.
Hunger makes me understand my poverty of soul, poverty of spirit, poverty of ends. Blessed are those, Jesus said, who hunger for righteousness. Admittedly, I don't get around to hungering much after righteousness, apart from the experience of physical hunger. As Cornelius Platinga observes, gluttony is an appetite suppressant for the things of God. My opinion or your opinion will not cut it.