“You only have one chance with teenagers,” says Margaret Smith, a teacher and mother of four. “If you make a mistake, they’re not going to believe anything you say. And you can’t tell them what to think: you have to invite them to make their own judgment.”

If we really needed to be reminded further of the dangers of smoking, reports this week warned that the difference in life expectancy in smokers and non-smokers has increased in the past 50 years — non-smokers now live longer because of economic, social and medical advances, but smokers still die as young as ever.

In the recent Wanless report on the nation’s health, smoking was highlighted as a huge threat. Of the 13 million British adults who smoke, 70 per cent have, at some point, tried to give up. And people are starting early: 1 per cent of 10 to 15-year-olds smoke regularly but, by the age of 15, this has increased to 24 per cent. We all know the health risks, so how do we prevent our teenagers becoming part of that sad 70 per cent, trying endlessly to kick the habit? “You can count me as a complete failure in that respect,” says Michael Rosen, a writer, broadcaster and non-smoker. “My three boys started smoking in their late teens, my stepdaughters in their early teens. I tried the rational approach, which is just two words: ‘It kills.’ Did it have any effect? Not a glimmer. Smoking is its own culture. It’s so much part of the way they are, the way they choose to live. The rationality comes in later, if it comes in at all.”

Certainly, just saying “don’t smoke” doesn’t seem to work. Kate Morris, a mother of three boys aged between 6 and 14, says: “When you say to a child ‘don’t smoke’, it’s almost as if you’re expecting them to. Our main tack is that we do not expect them to, so we don’t think they will.”

Ann McPherson, the co-author of Drugs: The Truth (OUP) and editor of a teenage health website, says: “Parents not smoking is the most important thing. If you don’t smoke, you can say, ‘You can’t smoke in my house’.” But it’s not always easy to lead by example and it doesn’t always work. Lois, a mother of three, who gave up recently, says: “They hated it when I smoked and I’ve told them why they mustn’t because it’s so hard to give up. But a lot of mothers smoke secretly.There’s a huge gap between what you expect from your kids and what you do yourself.”

Every parent who smokes has to endure complaints from their children. Then teenagers try it for themselves. Everyone dislikes it at first but some force themselves to continue. Why do they do it? “Teenagers have different reasons for taking up smoking,” Dr McPherson says. “Many feel pressure to try it. They want to experiment. They think it looks cool; there are role models who smoke. Groups of friends smoke together; it’s something to do with your hands. Girls think it helps control their weight.”

Kate, now a non-smoker, says: “I came to it as something that artists did. I enjoyed the whole thing of it — the white tip, the row of filters. I liked having something in my mouth without eating. There’s also an element of rebellion. If you were pissed off with life, I can see how quickly you’d want to be doing something like that.”

“Much has been blamed on the power of celebrity to glamorise smoking, particularly since the advertising ban. Harry, 14, has seen pictures of Kate Moss smoking, and admits: “You think it’s unlikely to do anything to you if she does it.”

Campaigners are asking for tighter controls on the way cigarettes and tobacco are marketed to young people. In the US, recommendations to schools include the banning of all tobacco manufacturers’ logos on clothing, hats and bags, and teaching children how to analyse the images before them. It seems the power of airbrushed celebrity appeals to the “I’ll never get old and ill” mentality.

Expert opinion has it that you have to start giving children the no-smoking message before they are old enough to read the warning on the packet — the British Medical Association recommends that schools target children as young as four.

Aidan MacFarlane, the co-author of Drugs: the Truth, agrees: “You have to start talking to children before they are fully exposed to smoking. Somewhere between 13 and 15 they start experimenting, which is fine — there are so many things they want to try out. Unfortunately, with tobacco, they are dealing with highly addictive substances, so parents don’t want to wait until they are already doing it.”

One view is that teenagers start smoking because they begin smoking marijuana joints. Margaret Smith, a parent and teacher, says: “They give up the dope but carry on with tobacco because, by then, they are addicted to it.”

“An approach which seems to be effective with teenagers is focusing on the evils of the drugs and tobacco companies,” says MacFarlane, “explaining how they are pushing cigarettes to young people in Third World countries and how they are destroying communities by felling forests and introducing tobacco crops. And there’s the dishonesty over health risks . . . young people have a sense of right and wrong and they often respond to that.”

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