The rules for fasting and abstinence in the Catholic Church are set forth in the Code of Canon Law for the Roman Catholic Church. To a limited extent, they can be modified by the conference of bishops for each particular country.

The Code of Canon Law prescribes (Canon 1250-51):

• Can. 1250: The penitential days and times in the universal Church are every Friday of the whole year and the season of Lent.
• Can. 1251: Abstinence from meat, or from some other food as determined by the Episcopal (meaning bishops, not Episcopalian Church) Conference, is to be observed on all Fridays, unless a solemnity should fall on a Friday. Abstinence and fasting are to be observed on Ash Wednesday and Good Friday.
• Can. 1251: the law of abstinence binds those who have completed their fourteenth (14) year. The law of fasting binds those who have attained their majority, until the beginning of their sixtieth (60) year. Pastors of souls and parents are to ensure that even those who by reason of their age are not bound by the law of fasting and abstinence, are taught the meaning of penance.

Fasting, broadly speaking, is the voluntary avoidance of something that is good. When Catholics talk about fasting, we normally mean restricting the food that we eat. We can fast between meals, by not eating snacks, or we can engage in a complete fast by abstaining from all food. The English word breakfast, in fact, means the meal that breaks the fast. While fasting takes the form of refraining from eating, it is primarily a spiritual discipline designed to tame the body so that we can concentrate on higher things.