Researchers say that children who try even a single cigarette are more likely to become habitual smokers, the BBC reported May 24.

Cancer Research UK reported that a study of 2,000 London students ages 11-16 found that those who tried cigarettes were twice as likely to become smokers, sometimes years after taking that first puff. "This is the first study that shows an early experience with one cigarette leads to smoking several years in the future," said study lead author Jennifer Fidler.

Researchers said that initiating smoking may cause a nicotine-related 'sleeper effect' among adolescents, and that prevention groups should discourage children from ever trying cigarettes. "It may be more important than previously thought to try and prevent children from trying even one cigarette and ... health professionals and those working in smoking prevention in schools need to be aware that those who have tried one cigarette, but are not smokers, are at risk," said Fidler.

But Simon Clark, director of the pro-smoker's group Forest, questioned whether any addictive mechanism was at work. "I accept that children who smoke a cigarette at the age of 11 may be more likely to take up smoking within the next few years but, whatever this report says, I suspect that has far more to do with immaturity, a rebellious personality, and a lack of parental guidance," he said.

The study was published in the journal Tobacco Control.