I've been up since five o'clock this morning. It's always nice when I get up before 8 on a Sunday morning, not only because I then have ample time to prepare for my Communion, but also because I can eat breakfast, since I typically attend Mass at eleven, and observe the three-hour fast before Mass.
In this time of Advent, when we are trying to dodge the commercialism of the season and engage with solemnity in the coming of Christ (even if not in the same penitential manner as in Lent), it's particularly appropriate to think of our disciplines. Here is what the Saint Augustine Prayer Book, by the Order of the Holy Cross, has to say about the Eucharistic fast.
The fast before Communion is not primarily an act of penance, but one of homage to our Lord, in order to receive the Blessed Sacrament as the first food of the day. It is normally a strict fast from both food and drink from midnight. At the Midnight Mass of Christmas it is natural and reverent, though not of obligation, to fast for some hours beforehand. No fast before Communion is required of those in danger of death. (And this is held to justify some relaxation in the case of those on active duty in the armed forces, for whom the fast from midnight may, if necessary, be replaced, according to widespread practice, by one of two to four hours, under the authority of Chaplains or others ministering to those involved.) Liquid food may be allowed to those seriously ill, or to those bed-ridden for over a month, but in such cases, no one should presume to "dispense himself," for the Priest who dispenses the Sacrament is the guardian of the Church's requirements, from whom a formal dispensation should ordinarily be sought.
Since the eucharistic fast is not penitential, it is not understood to prohibit smoking. However, common sense and good manners ought to regulate those things which do not fall within the formal regulations of the Church, such as smoking, the use of lipstick, propriety of dress, and personal cleanliness.
There is no law of the Catholic Church as to what hours of the day or night the Eucharist is to be celebrated. The law concerns only the fast before Communion, and thus the hour for celebration must be set according to the ability of the Celebrant and Communicants to fast from midnight previous to reception. Hence there is no justification for celebrating the Eucharist in the afternoon or evening, except those unusual circumstances indicated above, which may, by permission from the proper superior authority, excuse from the normal observance of the fast, namely, imminence of death or danger thereof, or absolute impossibility of normal reception of the Holy Communion.