Anyone with the remotest professional connection to food will have noticed how rapidly food fashions change. As one who, when young, was given 'tonics' to build my appetite and who now lives in a time when appetite suppressants are all the rage, I marvel at the separation of food from the appetite that demands it. While food may be good (not to mention necessary), is the appetite that leads us to eat bad? In a moral sense?

Well, that is the received wisdom. It may be said our appetites are some low part of our nature and should therefore be restrained on behalf of some higher goal: the 'Man does not live by bread alone' precept. I have noted with consternation the arrival of the 'new virginity' movement, directed at an appetite on which, as fully as our appetite for food, our survival depends.

Of all our fundamental appetites, only thirst suffers no repression: save for alcohol. Much of the sublimation of appetite to which we are summoned has, of course, a moral basis. We cannot eat without consuming something other than ourselves; therefore our appetite for food is harmful in that it is at the expense of something else. As we do not feed on the inorganic, what we eat is a 'living' substance, and who knows the pain that we might cause a leaf of lettuce, or a pig?

The idea that we are morally responsible for appetite, which has a physiological basis and would seem to be part of our natures rather than an acquired trait, is a curious one. None the less, if our 'higher' goal is emaciation, we must not eat, and since eating is natural to us, we must suppress that appetite by other means: discipline, ethical sense, or the use of other substances. While the idea of fasting is an old one - the odd 40 days in the desert did one's salvation a power of good - the purpose for which we are enjoined to sit on our appetites today is a little less high-minded.

It would seem that as we pay more attention to the animals on which we prey for food, and to nature, which provides much of what we eat, we are seeking to distance ourselves from the 'animal' and the 'natural' within us. My cat knows no such bounds. He acquires - by instinct or appetite - a variety of things purely as an expression of his appetite. He knows little difference at his young age between a worn slipper and a tempting moth. But we would not eat a slipper pie; moths are not on our menu; we control our appetite by choosing what we wish to eat.

This does not mean our appetite is not a curious thing and infinitely various. To me, the hours between eight and 10 in the evening are a sacred rite. I dispense entirely with communication with the outside world. When the telephone rings I growl ferociously on behalf of that appetite, which is not only for food but also for all its associated pleasures: company, conversation, wine, the prospect of sleep. My wife, however, exists happily as a rabbit: nibbling a stick of celery, crunching on nuts.

This, I hear, is healthy. We should eat when we need to, when we feel the appetite, and not in great set-tos. Perhaps it is the (fast disappearing) 'event' of a meal that is morally reprehensible and physiologically harmful? Nonsense. A household of occasional or periodical herbivores is no fit model for society. We would never meet, save criss-crossing at odd hours in search of sustenance. Our appetites are a part of us and highly individual; all humans have these appetites and must learn to cope with them; they are a shared part of our humanity. The culture of denial is also the cult of the self. You have but to note the self-satisfaction and narcissistic pleasure in those who have un-appetited themselves to know this.

I hope this is a passing fad. Unbridled appetites are an unhappy sight; so are bridled. Desire is not in itself bad, and when it is innate is seldom evil. Appetite is not only the basis of human survival, but also one of the chief ways in which we have civilised ourselves. The only animals who do not obey their appetites and do not eat are those who know they are about to die. They do not do it for reasons of fashion.