Fasting

Why do people who deny themselves food for a month report more pleasure in eating, not less?

The expected complaint from someone a month into a fast would be that food has become an obsession and eating a relief. What people actually report is stranger: that the meal breaking the fast is among the best they have eaten, that bread tastes of something, that they notice water. And they do not usually mean it was pleasant compared to hunger. They mean it was better than the same food eaten in an ordinary week.

That is the claim worth examining, because on the face of it denial should subtract from a life, not add to it — and traditions of self-denial have insisted for a very long time that it adds. Is there a mechanism there, or only a story told to justify the discomfort?

Begin with a small awkwardness about pleasure. If a good meal were pleasant in the way a stone is heavy — a property sitting in the object — the tenth spoonful would please as much as the first, and it plainly does not. So the pleasure is not in the food. It is in some relation between the food and the person.

Which relation? Separate two, because they behave differently and the tradition exploits both.

The first is bodily state. Michel Cabanac gave this the name alliesthesia: an identical stimulus is felt as pleasant or unpleasant depending on the internal condition of the person receiving it. His demonstrations concerned sugar solutions and temperature — the same warm bath is delicious when you are cold and unbearable when you are overheated. Nothing about the stimulus changed; the body's need changed, and the need is part of what the pleasure reports. So a hungry person eating bread is not imagining the improvement. The bread really is worth more to them.

The second relation is a standard of comparison. Satisfaction is largely a judgement against what you have come to expect, and expectation tracks recent experience — which is why, as hedonic adaptation sets out, a sustained improvement stops registering within months while nothing has been taken away. Run that backwards. If constant availability drifts the standard upward until ordinary food returns nothing, the standard can also be driven down: withdraw the thing, and the reference point falls to meet the new normal.

Now the fast is legible. It is the inverse of hedonic adaptation, deliberately applied. Where adaptation happens to you and dulls what you have, a fast turns the same dial the other way, and the dulled pleasure returns because the gap it measures has been reopened.

Two mechanisms, then, worth keeping distinct because they run on different clocks. The bodily one is fast and self-limiting, spent within the first minutes of eating — which is why the first mouthful carries almost all of the reported intensity. The comparative one is slow and outlasts the meal, which is why people describe food as tasting different for some while afterwards.

Does that get us to more pleasure, though, rather than restored pleasure? Strictly, no — and I would rather mark the gap than paper over it. Resetting a reference point returns you to where you began; it does not obviously overshoot. Two further things are doing work, and both concern attention rather than physiology.

Scarcity compels attention, and a great deal of ordinary eating is unattended; pleasure nobody notices is close to no pleasure at all, and a fast makes inattentive eating impossible for a while. And the fast supplies a boundary. A meal ending a month of abstinence is an event with an edge on it — anticipated for hours, timed to a moment, usually eaten with others who waited too. Anticipation is itself a pleasure, and a distinct one from consumption.

This is where the practice reveals its own instability, and the traditions know it. Adaptation is indifferent to what it adapts to; it works on the fast as readily as on the feast. A discipline observed punctually every year becomes the normal shape of the year, at which point it has a new baseline and resets nothing. The philosophical versions keep the denial irregular and unwelcome for that reason — Seneca, in the Letters, advises setting aside a few days now and then to live on the coarsest food and roughest bedding, and asks whether this is really the condition one feared. His concern is with what the exercise reveals about the fear, not with the taste of the bread afterwards.

Two honest limits. Reported pleasure is not measured pleasure, and a religious fast arrives bundled with company, expectation, achievement and significance — none of which the reference-point account explains and all of which would raise a report. Nobody has separated those contributions cleanly, so far as I know. And the strong ascetic claim, that denial is a technique for enjoyment, goes well beyond what any of this establishes. The mechanisms support something narrower: that continuous supply erodes the pleasure of a thing, and interruption restores it.

The tempting misreading is that fasting sharpens the senses — that the tongue becomes more acute. Neither mechanism says that. The signal from the tongue may be identical; what changes is the value the body assigns it and the standard the mind compares it against. Which explains why the effect is specific to what was given up, rather than a general improvement in perception.

It is also worth separating two things a tradition might be claiming. One is the descriptive point above, which is broadly supportable. The other is that appetite curbed is appetite governed — that someone who can go without stands differently to the thing than someone who merely has enough of it. That is a claim about freedom rather than pleasure, and nothing here establishes it. It is also why the traditions rarely present the returning taste of bread as the point: if it were, the fast would be a strategy for eating better, close to the opposite of what is intended.

• Whether the same logic explains seasonal foods, and what year-round availability costs.

Every term the collection defines is gathered in the glossary.