Imagine an agricultural world just one step away from our own, where the little chickens, realising that their puffy breasts are below accepted standard will prance about trying to enhance them. Happy porkers will trotter along treadmills to reduce their bellyfat and guzzle hormones and nutritional supplements for ever leaner, ever healthier meat. Cows will delay reproducing to improve their career possibilities in milk production. Sheep will still follow one another; but now they make sure you know they do it out of choice. Animals, after all, are bred for a purpose; surely if they could be encouraged to take that purpose to heart and follow a voluntary route to improved consumability we would be entering a perfect future?

Of course not. That would be silly. Imagine any creature voluntarily starving itself, consuming chemicals, undergoing surgery, developing a punitive exercise routine, restraining its natural behaviours and conditioning to behave contrary to instincts of hunger and psychological independence. It would never happen. Unless, of course, there was a movie deal involved. At which point it's out the window with notions of heterogeneity and free will and howdy to the human factory farm.

We judge movie stars by different criteria from the rest of humanity, like veal calves held up against against beef. We feel free to bitch about their various weight fluctuations, and the comings and goings of curves, pecs and abs, in the most personal fashion, but is it entirely our fault? There is a peculiar self-imposed freakishness to their behaviour of, in particular, American actors, that seems to invite such criticism. It is not simply that they starve themselves; and most, from Audrey Hepburn onwards seem to have done so; but that they impose such a twisted logic onto the process.

One is not dieting, or losing weight (because that would be, like, relenting to oppression, wouldn't it?) one is simply eating fat free, one has allergies and special dietary requirements. And it is not just slinky malinkys like Courtney Cox and Callista Flockhart I am thinking of here (although believe me, those girls starve themselves to look like that), but not entirely scrawny, apparently sensible human beings.

Let us take, for example, Gillian Anderson, otherwise known as Agent Scully of X-Files fame. Miss Anderson's idea of gustatory pleasure is a decaf non-fat coffee, but the fact that she has been drinking them recently is a sign for her that her life is going somewhat off the rails; otherwise she takes her coffee with rice milk as part of her fat-free, wheat-free, oil-free, carbohydrate-free, sugar-free, dairy-free lifestyle. Yum. By Hollywood standards, Miss Anderson is not thin, frankly she looks kind of normal, which makes one wonder what all the others look like in real life, and what the hell they actually eat.

There is a part of most of us that wants to be a movie star, and inevitably as these nuggets of dietary information slip out they are gobbled up by an eager public. Since 90 per cent of the Hollywood wanabees seem to flock in on California, self-imposed battery farming techniques for humans have made it biggest there from the outset; it's a phenomenon so well documented that for years I thought that Silicone Valley was some kind of reference to breast implants.

While movie stars were once associated with a life of decadence and luxury, they now all seem to be promoting a near Calvinist sense of asceticism. Without their glittery lifestyles to aspire to (however fictional) we ape instead their religious zeal: indulgence in food is sinful, those not undertaking a punitive exercise regime are letting themselves go, vitamin pills are no longer a supplement but a necessity.

As we celebrate the arrival on our screens of sitcoms like Babes In The Wood showing "normal", "beautiful" people, instead of the deformed harridans of British tradition, one wonders how far we are from a culture that celebrates unrealistic and uniform physical appearance. Already hundreds of thousands of Brits regard the consumption of a slice of chocolate cake as a fall from grace. While we cringe at Scientology and giggle at culty religious trends amongst the tinsletown angels, we have not stopped to examine the belief system that we have already embraced.