We are required to receive the Holy Eucharist at least once per year, and the Church urges the faithful to receive the Holy Eucharist requently. When we receive the Holy Eucharist, we receive the True Presence of Our Lord Jesus - Body, Blood, Soul and Divinity.
In order to be properly disposed to receive Communion, participants should not be conscious of grave sin and normally should have fasted for one hour. A person who is conscious of grave sin is not to receive the Body and Blood of the Lord without prior sacramental confession except for a grave reason where there is no opportunity for confession. In this case, the person is to be mindful of the obligation to make an act of perfect contrition, including the intention of confessing as soon as possible (canon 916). A frequent reception of the Sacrament of Penance is encouraged for all. (USCCB - Guidelines for the Reception of Communion)