When will parents start to grow up?

The people our young teenage girls ape are the women nearest to them - that's mum and her friends

It doesn't follow that if a little girl smears pink gloss over her lips and sports a tiny mini-skirt, she's wilfully trying to pull a boy. And spending hours reading about "fit lads" doesn't mean that she wants to start having sex. If she wants "dating tips", it doesn't mean she's about to start giving blow jobs behind the bike sheds.

It doesn't follow that if a little girl smears pink gloss over her lips and sports a tiny mini-skirt, she's wilfully trying to pull a boy. And spending hours reading about "fit lads" doesn't mean that she wants to start having sex. If she wants "dating tips", it doesn't mean she's about to start giving blow jobs behind the bike sheds.

A survey this week shows that nine out of 10 girls are now using make-up by the age of 14, and an opinion poll for the BBC reveals that 86 per cent of us want tougher restrictions on the images used in children's programmes and magazines. It's easy in this instance to put two and two together and make five. How we adults love to dump a whole load of blame on someone else - magazine editors, television programme makers, the script writers of EastEnders, shameless pop hussies like Christine Aguilera, and even Kate Moss, skinny single mum, smoker and style icon.

In the newsagents, there are now several "zones", from the top shelf down, where magazines about motorbikes and heavy metal nestle next to DIY and decorating tomes from cheap and cheerful to Country Life and World of Interiors. At the very bottom, toddler level, are the comics like dear old Beano, still going strong. Next up are several shelves packed with the offending teen mags, Bliss, Shout, Mizz, M, Go Girl, Sugar and Mad About Boys. To their front covers are lashed free gifts of lip gloss, rucksacks and eye shadow.

Following their survey of young teens and their spending habits, Mintel concluded that make-up vending machines should be placed in spots where their target age group hang out - in schools, bowling alleys and cinemas. There was a predictably outraged reaction. But all the marketing company was doing was highlighting the fact that teenage girls can be sold even more products than at present if they are carefully targeted.

Personally, I'd like to see all vending machines removed from schools, and all secondary schools imposing a uniform up to the age of 16 right across the country. I wish we'd stop pretending schools are fun-packed "academies" or whatever - schools are schools, places where you go and learn stuff, without which you won't get a job. They aren't places to buy Coke, bottled water, snacks or lipstick. They are schools, moderately dreary establishments that are best used to cram as much stuff as possible into your head if you want to earn enough to buy all this other stuff later.

Replace citizenship classes with compulsory cookery and we'll soon have obesity under control. Impose uniforms and you stop teenagers trying to look like someone from a Britney video at the bus stop each morning, and gangs stabbing each other for trainers. Impose compulsory no-nonsense lunches and five hours of PE a week, and those flabby kids will soon change shape.

If we care about our kids, we'll have to be tough. But what about their troubled journey through adolescence? Has their precious childhood really been eroded, and if so, who is responsible? Sure, sexually transmitted diseases among teenagers have gone up by 30 per cent, but are we adults really great role models?

Recently, the Association of Teachers and Lecturers wanted age restrictions placed on teenage magazines, claiming that their content corrupted the very young. In fact, the reverse is true. If you can bear it, go and buy the latest Mizz, which contains an article about a young girl suffering from Crohn's disease. The fashion is photographed on real readers (unlike Vogue) and is hardly slutty. A girl who is overweight is told to drink plenty of water and to cut down on junk food.

An article in Bliss which shows girls how to look five years older focuses on one 14-year-old who moans about only being five feet tall. Who didn't want to look 18 when you were dreary old 14? It's hardly a new concept. A reader who claims her teacher "fancies" her is told in no uncertain terms to stay away from temptation because the man in question could lose his job. Problems are answered by a psychotherapist. A young musician talks about growing up with a mum who belonged to the controversial Children of God cult. Sneak magazine tells readers it's illegal to have sex under 16, and always to use a condom.

Most of these magazines are edited by savvy young women who understand that the only way to get young women to change their behaviour or understand the world around them is through their peers, hence the emphasis on real-life stories. Teenage magazines like these play a crucial role in education when communication with mum is at its most confrontational, not to say minimal.

Magazines have strict guidelines. There's TMAP, the Teenage Magazine Arbitration Panel, which ensures that sexual issues are addressed in an age-appropriate way. The trouble, it seems to me, is not the number of young girls slapping on sparkly nail varnish or colouring their hair, but what happens when they start to read the stuff in publications aimed at their older sisters or mums.

We buy millions of magazines every week from Heat downwards, which feature nothing but disgusting pictures of "celebrity" figures in sweat-stained dresses, laddered tights or barely-there dresses. Captions delight in cutting any woman who strays from perfection right down to size in the most aggressive terms. Fashion magazines for most women still consistently photograph designer clothes on anorexic models - little change there over the years. Every woman's magazine going has a feature on breast cancer - the disease of the moment - because it sells copies. I can't tell you how repulsed I am by yet another chemotherapy diary - a whole repugnant branch of journalism is feeding off misery and instilling anxiety.

The people our young teenage girls ape are the women nearest to them - that's mum and her friends, and the women this older generation are interested in, from soap stars to actresses. So if mum starts sticking her daughter in designer clothes, the rot has set in. If mum sits around the kitchen table swigging wine night after night, she can't be surprised when her daughter latches on to alcopops. If mum shells out money to read drivel like Geri Halliwell's latest utterings in the bestselling Glamour magazine, then she can't be surprised when her offspring stops eating and starts throwing up.

Has everyone forgotten how Geri waffled on and on about her "healthy" eating plan and her "sensible" diet and her physical fitness. Now Ms Halliwell attends a recovery programme for bulimics and lives in LA, but to judge from her Glamour cover picture, she still submits to the full glory of airbrushing to ensure every curve is not too curvaceous. Geri has never said to any of her fans: "I'm sorry I didn't come clean about my addiction to food until I published my autobiography, and I regret letting millions of young girls think that they could look like the thin me if they ate the right things and did a lot of yoga."

As long as women everywhere pay for magazines which run features about "The Porn Star who caught HIV" and "Meet your five sex personalities", we need not look very far for the person who kissed goodbye to our children's innocence. It's all of us. So stop telling me it's someone else's problem, be it a teacher, a pop star or an editor. Isn't it about time parents decided to be parents?