Fridays of Lent: Catholics, 14 years of age & older, are obliged to abstain from meat.
Ash Wednesday & Good Friday are days of fasting & abstinence. Catholics between the ages of 18 and 59, are obliged to fast, i.e., one full meal only. Two lesser meals are permitted; all meals must be meatless.
For more information about Lenten practices and fasting and abstinence, see the Lent page under Worship & Liturgy > Liturgical Seasons.