This article concerns HOLY COMMUNION.

taken from The Catechism of the Catholic Church:

1408 The Eucharistic celebration always includes: the proclamation of the Word of God; thanksgiving to God the Father for all his benefits, above all the gift of his Son; the consecration of the bread and wine; and participation in the liturgical banquet by receiving the Lord’s body and blood. These elements constitute one single act of worship.

1411 Only validly ordained priests can preside at the Eucharist and consecrate the bread and wine so that they become the Body and Blood of the Lord.

1414 As sacrifice, the Eucharist is also offered in reparation for the sins of the living and the dead to obtain spiritual or temporal benefits from God.

1415 Anyone who desires to receive Christ in Eucharistic Communion must be in the state of grace. Anyone aware of having sinned mortally must not receive communion without having received absolution in the sacrament of penance.

1417 The Church warmly recommends that the faithful receive Holy Communion each time they participate in the celebration of the Eucharist; she obliges them to do so at least once a year.

taken from the Catholic Answer Book, OSV

Q. Is there still a rule on fasting before Communion. I see so many people chewing gum and eating candy that I wonder.

A. The Eucharistic fast is quite simple nowadays: abstinence from all solid foods and liquids for one full hour before receiving Holy Communion. A much mitigated fast applies to the sick. Water does not break the fast, nor does medicine.

The reason for the fast is to serve as apart of one’s preparation to encounter the Bread of Life. Physical hunger reminds a person of that deeper hunger which can be satisfied by Christ alone.

Aside from breaking the Eucharistic fast, activities such as you describe are gross violations of common courtesy, let alone indicators of irreverence for the church and the One whose house it is.

Q. At Mass on Christmas morning, the priest announced that we could receive Holy Communion again even if we had done so the night before. Was he correct? I thought Communion could be received only once a day?

A. Yes, the priest was right. The revised Code of Canon Law does permit the reception of Holy Communion twice in one day, with no special reason having to exist. However, no more than twice is possible, regardless of circumstances. That decision was made recently by the Roman Commission for the Authentic Interpretation of the Code.

I must say that I was somewhat concerned that in not a few letters writers have suggested that attendance at Mass is useless if one does not receive. What about divorced-remarrieds then? More than that, however, this often-repeated opinion reveals a mistaken understanding of the Mass: the central act of the Eucharist is Christ’s self-oblation to the Father. This is Christ’s action – not ours. And it is of value, no matter what we do. Certainly, the celebration of the Eucharist takes on added meaning when someone receives Holy Communion, but the objective merit of the Eucharistic sacrifice is the completed, redemptive action of Jesus Christ, sacramentally re-presented upon the altar. To assert otherwise is to confuse divine initiative and human response.