釋氏要覽 1.409

1.409

The Fotidi lun states: Sustaining is called food; it means being able to sustain the physical body, preventing it from breaking down, and nourishing wholesome dharmas. Furthermore, it has the meaning of nourishing and benefiting. If it is not yet eaten, or has entered the stomach but is not yet digested, or causes illness, none of these constitutes the meaning of food. Only when it passes through the mouth, enters the stomach, is digested, flows into the five viscera, pervades the four limbs, supplements qi, and benefits the flesh, does it constitute the meaning of food.