It is pretty tricky to tell that a cultural nadir has been reached in an age when stars are photographed openly leaving nightclubs with clods of cocaine in their nostrils and Gordon Ramsay says the F-word 57 times in one prime-time hour of Kitchen Nightmares. (My baffled nine-year-old counted.) But if a sticker printed in Heat magazine this week mocking a blind and profoundly disabled boy called Harvey — son of Katie Price, aka Jordan — doesn't mark some new low, what possibly could?

First let's get one thing straight: this sticker, which has a picture of the child's face mouthing the words “Harvey wants to eat me”, didn't just slip unnoticed into Heat. It was not a whoops moment by one junior underling. Stickers are expensive for a magazine and thus carefully produced weeks ahead of the issue itself. There would have been a stickers brainstorm meeting — where some Algonquin wit evidently suggested having a duckling uttering the phrase “Show us your c**k” — then a picture editor, designer and sub-editor would see them, before they were finally signed off for printing by the Editor himself.

At least ten highly paid, clever people, I'd guess, and not one queried whether mocking a child suffering from septo-optic dysplasia, which counts clinical obesity among its lesser symptoms, was a hilarious idea. “It was never our aim to make fun of Harvey's disabilities,” said Heat's publisher Emap. But what was the aim then, exactly? That schoolkids slap Harvey's image on each other's backs or bags, have a laugh at this “funny-looking” kid? How were parents of other Harveys supposed to regard it, whose deepest dread is their disabled children end up outcasts, mocked by cruel peers?

I wonder about the other stickers too. “Posh will you f***ing smile” and “I hit Charlie”, referring to a Big Brother contestant, recently so badly beaten she wears a neck brace. Or the baffling “I'm not on drugs, it's my bipolar medicine”: yes, the mentally ill, aren't they a gas!

You may think this is all just piffling stupidity by a trashy celebrity magazine. But 550,000 people buy Heat every week, around a million read it, most of them under 30. Recently at a magazine industry dinner Alastair Campbell told me he'd forbidden his teenagers from bringing Heat into his home. “It poisons the minds of women and children,” he said. I thought he was being a tad pompous, as did his partner, Fiona Millar, who rolled her eyes. But I was remembering the camp, naughty, teasing yet affectionate, PR-puffery-puncturing Heat of a few years back and how last year its Editor, Mark Frith, won the most prestigious award in magazines, the Mark Boxer Trophy, at the age of just 35.

Something has changed. Celebrities are now discussed in a harsher, crueller, uglier tone, verging at times on violent and hateful. They are no longer just actresses or pop stars or silly wannabes, but specimens for cold-blooded dissection. Behind the gates of her LA mansion, Victoria Beckham is probably inured to the headline “Posh's new misery”, just as Angelina Jolie, snuggled up to Brad, isn't worrying what Heat thinks about her “pathetic arms”. But this dehumanised discussion coarsens us all. It has chipped away at the souls of Heat employees so that their sick office humour leeches into a national publication.

Of course it comes down to cash. Heat sales are flagging, there was a recent proliferation of celeb titles screaming for readers, including a couple of pond-feeders — New! and Star! — owned by pornmeister Richard Desmond. Cruel sells. Which is why, if no one on TV is breaking up with a boyfriend or tumbling into rehab that week, the default cover story, repeated 20 times a year, is “Stars who hate their bodies”. Yes, hate: an ever-renewable resource.

The Harvey business makes me wonder if it could soon be acceptable to call someone a “spastic” again? You know, ironically, as a joke. Irony was the Trojan horse in the Loaded-era mid-Nineties for smuggling in long-dead sexism, so it was permissible once more to call women “babes” or attend lap-dance clubs, all as some achingly clever, postmodern gag.

Certainly humour about disability is no longer taboo: Little Britain has “wheelchair-bound” Andy, whose carer is unaware he can secretly walk, and in an episode of Extras Ricky Gervais mistakes a cerebral palsy sufferer for a lolling drunk. Clearly Heat staff cannot see the subtle line between these comedies of embarrassment — whose butt is the ignorance and pretension of the able-bodied — and laughing at a fat, autistic blind boy.

Yet it is hard to shed a tear for Harvey's mother, the pneumatic Jordan who has whored him and her other children since birth — even in utero — in lush and lucrative photospreads in more sycophantic magazines than Heat. Indeed, for obtaining commercial sponsorship for every moment of her life, Jordan is often dubbed a shrewd businesswoman, a role model and once, unbelievably, voted “mother of the year”, a title also awarded to a drug ravaged, Kerry Katona, and which perhaps Rose West will one day receive posthumously.

Yet given that the Press Complaints Commission code states that no child's picture should be published without parental permission, you might wonder why Heat felt able to use this photo of Harvey at all. Well, many editors don't rigidly adhere to the code. Mostly they make a judgment call based upon how much the parent concerned has “invaded their own privacy”. In other words, any star who welcomed OK! inside her baby's nursery cannot object to a snatched snap outside Waitrose. And they gamble on the PCC coming to the same conclusion.

Stars such as Ewan McGregor (who successfully sued a Scottish newspaper for printing photos of his daughters on holiday in Mauritius) and Jude Law strive to keep their children out of the spotlight and therefore magazines and newspapers will usually pixillate their offsprings' faces. Harvey Price, however, is fair game.

But this time Jordan has complained to the PCC and the commission's decision will set a forceful precedent. For stars, an excess of unwanted attention is the price of their wealth and renown: but their kids have enough trouble avoiding being screw-ups without press persecution. Even if Jordan has her ladygarden shaved into a likeness of the Turin Shroud and shows it off on GMTV, this is no reason to punish her child.

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