The Christian faithful are to do penance through prayer, fasting, abstinence, and by exercising works of piety and charity. All Fridays through the year, and especially during Lent, are penitential days.
ABSTINENCE: All who have reached their 14th birthday are to abstain from eating meat on Ash Wednesday and on all Fridays during Lent.
FASTING: All those who are 18 or older, until their 59th birthday, are to fast on Ash Wednesday and Good Friday. Only one full meal is allowed on days of fast. Two other meals, sufficient to maintain strength may be taken according to one’s need, but together they should not equal another full meal. Eating between meals is not permitted, but liquids are allowed. The obligation does not apply to those whose health or ability to work would be affected seriously.