The Eucharistic fast promotes a deeper reverence and respect for this Sacrament, which is not ordinary food; it is the Panis Angelorum, the “bread of angels”. 

St. John the Baptist prepared the way of the Lord with fasting and penance, because fasting makes room in the heart, mind, body and soul for the Lord.  We fast before Holy Communion for the same reason: to prepare the way for the Lord; to make room for Him; to “clean house”.

The human body and soul are so closely connected that the soul is prepared for a more fruitful reception of the Blessed Sacrament when the body is denied the comfort and satisfaction of eating or drinking.  The one-hour fast increases mental alertness and fosters a deeper hunger in the soul to become united with Our Lord.

This discipline does not apply to the sick and elderly: the elderly and those who are suffering from some illness, as well as those who care for them, may receive the Blessed Eucharist even if within the preceding hour they have consumed something.