The Code of Canon Law prescribes (Canons 1250-1252):
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 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. 1252: The law of abstinence binds those who have completed their fourteenth year. The law of fasting binds those who have attained their majority, until the beginning of their sixtieth 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 true meaning of penance.
In the United States, the U.S. Conference of Catholic Bishops has declared that "the age of fasting is from the completion of the eighteenth year to the beginning of the sixtieth." The USCCB also allows the substitution of some other form of penance for abstinence on all of the Fridays of the year, except for those Fridays in Lent. Thus, the rules for fasting and abstinence in the United States are:
- Every person 14 years of
age or older must abstain from meat (and items made with
meat) on Ash Wednesday, Good Friday
and all the Fridays of Lent.
- Every person between the
age of 18 and 60 must fast on Ash Wednesday and Good
Friday.
- Every person 14 years of age or older must abstain from meat (and items made with meat) on all other Fridays of the year, unless he or she substitutes some other form of penance for abstinence.
If you are outside the United States, you should check with the bishops' conference for your country.