Doug Hovey, 26 and his girlfriend Melissa Aleman, 23, eat a stack of pancakes at Ihop during National Pancake Day on Tuesday Feb.20, 2007. National Pancake Day, also known as Mardi Gras, Shrove Tuesday and Fat Tuesday has been celebrated for centuries in England the day before Ash Wednesday, to use up their supply of eggs, milk and butter, which are prohibited during Lent.  Shrove Tuesday is the last day before the period which Christians call Lent. This day is one of the moveable feasts in the church calendar and is directly related to the date on which Easter falls. Shrove Tuesday always falls 47 days before to Easter Sunday, so the date varies from year to year and falls between February 3 and March 9. The reason that pancakes are associated with the day preceding Lent is that the 40 days of Lent form a period of liturgical fasting, during which only the plainest foodstuffs may be eaten. Therefore, rich ingredients such as eggs, milk, sugar and flour are disposed of immediately prior to the commencement of the fast. Pancakes and doughnuts were therefore an efficient way of using up these perishable goods, besides providing a minor celebratory feast prior to the fast itself