First let me say: Don’t complain! At one time, you couldn’t have a glass of water before attending Mass. In fact, you couldn’t eat or drink anything after midnight on the day you were going to receive holy Communion. The “Eucharistic fast,” as it is called, is an important part of preparing to receive Holy Communion. While the tradition has changed over the years (dare I say, “watered-down”), under most circumstances, the fast is still required. The most recent definition of the Eucharistic fast comes from Pope St. John Paul II. Whoever is to receive the Eucharist is fasting for at least one hour before Communion from all food and drink, with the exception of water and medication. The fast, by the way, never applies to the elderly (at least 60 years old, usually) or the sick (and their caretakers, too) unless they wish to do so. And, if you are curious, the Eucharistic fast is also required for priests, unless they have already celebrated a Mass that day. Then the priest is allowed a little nourishment if he wishes.
Now, some will want to play the game, “Is it an hour before Communion or an hour before Mass?” Well, the guideline does instruct “before Communion.” So I guess, technically, you could pray that there be a particularly long homily at Mass to ensure it’s been an hour before receiving Communion. If someone wants to split hairs, I suppose they could. But it’s missing the point of why the Eucharistic fast exists. So why not have a bite or toast? Why not have that cup of coffee (yes, that too) right before Mass?
Historically, Jewish religious customs frequently involved fasting. So it makes sense that the early Christians would continue to follow the practice. But outside of mere tradition are some additional things to consider. For instance, hearing our stomachs grumble a bit reminds us of the fasting that Jesus underwent numerous times in the Gospels. It helps remind us to hunger for the Eucharist. It’s a way of practicing humility before receiving the body and blood of our Lord.
Pope St. John Paul II once wrote, “ ... what one finds most often is not so much a feeling of unworthiness as a certain lack of interior willingness, if one may use this expression, a lack of Eucharistic ‘hunger’ and ‘thirst,’ which is also a sign of lack of adequate sensitivity towards the great sacrament of love and a lack of understanding of its nature.” Be ready to receive the Lord. Make it much more than “going to communion.” Hunger for the Risen Jesus; thirst for him.
Besides, you can have toast anytime. Receiving Jesus is only at special times, and brings grace that no other food could ever match.