In the United States, Catholics age 14 and older are required to abstain from meat on Ash Wednesday and the Fridays in Lent. (Meat is considered to be the flesh and organs of mammals and fowl and soups or gravies made from them, but not saltwater or freshwater fish, amphibians, reptiles and shellfish or food products such as margarine and gelatin derived from animals which do not have any meat taste.)
Catholics age 15 through 59 are required to fast on Ash Wednesday and Good Friday. (Fasting means refraining from consuming food or drinks considered to be food outside of one regular meal and two smaller meals each day. The smaller meals, if added together, should not exceed the main meal in quantity.)
Catholics should abstain from any food or drink, except water or medicine, for at least one hour before receiving Holy Communion.
Individuals are excused from fasting and abstinence if they are sick, frail, pregnant, nursing, have other disabilities which make it difficult to understand or observe the practice; also excused are manual laborers who need more sustenance, guests who cannot excuse themselves from a meal without giving offense, and individuals in other situations of moral or physical difficulty or situations in which fasting or abstinence would prevent them from carrying out their responsibilities.