Emile Durkheim, the French sociologist who, in fact, formally established the discipline of sociology, was a keen observer and scholar of religion and ritual. To him, sociology was the science of institutions, understanding the term in its broader meaning as the "beliefs and modes of behavior instituted by the collectivity," with its aim being to discover structural "social facts." Now, why are we going on about a French sociologist in a piece about festivals and fasting? It is because individuals experience the social as a fact over and above their own individuality and therefore recognize this factual reality outside themselves in symbolic forms and ritual actions. which is all a roundabout way of saying that celebration and the rituals that come along with it are integral parts of how societies across the world work.
Festivals mark rites of passage; they mark occasions in the community; they celebrate the receipt of bounties that communities may consider the grace of God—simply put, festivals and celebrations keep communities together.
But why are festivals associated with fasting? Why are celebrations punctuated by depravations? There is no major religion in the world that is not associated with some kind of ritual fasting. Some scholars believe that self-denial expresses a public recognition of unworthiness. That fasting may show a desire to go past what circumstances surround us into a better outcome. To gain something, you've got to lose something. And what greater pleasure is there to lose than God’s own gift of food? "I’ll give up the thing I like best for you; that must mean I value you more than I value the thing that brings me the most joy; so, you must recognize me and reward me" is the underlying conversation between devotee and god and the foundation of fasting. That is the opinion of some scholars, anyway.
As with so many rituals, fasting is not restricted to one religion. Of course, we all know about Ramadan, of course. The preparation of Jesus for his ministry sent him for forty days and forty nights into the wilderness—an aspect repeated in the Lenten season by believing Christians. Hindus have a plethora of festivals and even just days of the week where the devout keep a fast. The most commonly observed fast, Ekadashi, is observed approximately twice a month, on the eleventh day of each ascending and descending moon.
Therefore, fasting is imbued with great meaning. It is not merely the rejection of food. It is the rejection of food in submission towards something greater, a better outcome. Which is why the fasting undertaken by women who keep the karva chauth vrat often come for criticism. While it is easy to justify the fasting as "ritual" or "age-old practice," a closer study of the why behind the fasting exposes matters we may not necessarily be too comfortable understanding.
Fasting has also moved beyond its merely spiritual and religious role. Mahatma Gandhi is the greatest example of this. He was an ardent supporter of fasting out of religious conviction and as a way of "freeing oneself of the constraints of the body," but he also used fasting as a means of exerting political pressure. The number of hunger strikes he went on is an effective example of beseeching the powers that be to grant what one needs. He engaged in several hunger strikes to protest against the violence committed, notably between Hindus or between Hindus and Muslims. Several of his fasts lasted as many as 21 days.
Bhagat Singh, one of the most famous practitioners of the hunger strike, fasted for 116 days, ending with the British succumbing to his wishes. Fasts can move notions, and indeed, even make nations. Potti Sriramulu, an ardent Gandhian, was an Indian revolutionary who died after undertaking a hunger strike for 58 days in 1952, after Indian independence, in an attempt to achieve the formation of a separate state, to be known as Andhra State. In fact, his death became instrumental in the linguistic reorganization of states.
Ireland, perhaps even more than India, is known for its history with the hunger strike. Hunger strikes have deep roots in Irish society and in the Irish psyche. Part of a much older tradition within Irish society, mostly with religious underpinnings, it was used as a political tool in the 20th century. As many as 22 people died of hunger strikes in the last century in Ireland. As late as 1981, hunger striking was the method most famously used by protestor Bobby Sands, played memorably by Michael Fassbender in the film "Hunger." Sands ultimately succumbed.
So, if you thought fasting was merely ritual, think again. Its metaphysical foundations run far deeper than skipping the occasional meal.