It was Shrove TuesdayThe day before the beginning of Lent. To "shrive" yourself means to confess your sins, as people were supposed to do on that day., and the woman making pancakes in her medieval kitchen had lost track of the time. Suddenly, she heard the church bells start to ring. "Help!" she thought. "I'm going to be late for the service!" And she rushed out of the house in such a panic that she forgot to take off her apron - and put down her frying pan.

This, according to tradition, is how pancake races started. The reason the woman was making pancakes was that for the 40 days of Lent, food such as eggs were forbidden, so they needed to be used up before it started.

For Christians, cutting down on enjoyable food is a commemoration of the 40 days Jesus spent fasting in the wilderness. St FrancisAn Italian born in around 1182, who gave up his wealth as a young man to become a monk. He inspired many followers and was known for his love of nature. is said to have spent the whole of Lent alone on an island in an Italian lake, living on half a loaf of bread.

Though many Christians now just give up one thing, such as alcohol, some - particularly in India and Pakistan - adhere to the ancient "Black Fast", which forbids meat and dairy products and allows only one meal a day, eaten after sunset. In this, it strongly resembles the Muslim festival of RamadanThe ninth month of the Islamic year, during which Muslims are required to fast from dawn until dusk..

Such asceticism is important to other religions too. Hindus fast on certain days of the week and month, and during festivals such as NavaratriAn autumn festival whose name means "nine nights", celebrating the victory of good over evil.. The BuddhaThe founder of Buddhism. Born Gauthama Siddhartha in Nepal in around 563BC, he left his princely family to seek wisdom. fasted so rigorously that he said, "My ribs stuck out like the rafters of an old hut," before deciding on a more moderate form.

JainismAn Indian religion which emphasises respect for all living creatures. includes the idea of "santhara" (fasting to death) and around 200 followers are believed to end their lives in this way each year. Although it is intended only for those who are near death anyway, it is the subject of legal controversy in India where some regard it as attempted suicide.

In Judaism, self-denial can go beyond fasting: during Yom KippurA festival which comes nine days after the Jewish New Year. The name translates as "Day of Atonement"., it is forbidden even to brush your teeth. Extremely observant Jews refrain from using electrical devices, including TVs and computers, on the Sabbath.

The 21st-Century equivalent of a religion, some would argue, is wellness - and many of its practitioners advocate self-deprivation. The popular 5:2 diet is based on intermittent fasting, with five days of normal eating followed by two days restricted to just 500 calories.

Some say that giving things up restores the natural balance in a world where many rich consumer societies enjoy massive excess. Our hunter-gathererSomeone who lives by hunting wild animals and collecting wild plants. ancestors were used to feast or famine: if they killed a wild animal, they quickly ate it all. If food was scarce, they made do with little or nothing. And if we want to make life on the planet sustainable, we all need to cut back.

Others argue that it is not particularly healthy or scientific to live a yo-yo existence. The people who live longest have regular habits: they get up and go to bed at the same time every day, following the body's natural rhythms, and have their meals at a set time, eating neither too much nor too little. They also stick to the same basic foods year in and year out.