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Teenagers who feel relaxed after their first drags on a cigarette are most likely to become addicted to smoking, a sign that some people's brains are more susceptible to nicotine, say researchers.
"We know that nicotine can have an immediate impact on the brain and yet we also know that not every adolescent who tries a cigarette gets hooked," said researcher Dr Joseph DiFranza, of the University of Massachusetts Medical School.
While peer pressure and other factors may lead young people to try smoking, it is the brain's response to that first dose of nicotine that most likely determines who gets addicted. Experiencing a feeling of relaxation in response to the first cigarette was the strongest predictor of addiction, the study found.
It said one theory suggested nicotine suppressed pathways in the brain that generated the feeling of craving, which was experienced as relaxation. That, in turn, created a craving for nicotine when the drug was absent.
Over the four years of the study between 2002 and 2006, 11 interviews were conducted with 1000 teenagers. Of the 217 who tried smoking during the study, nearly one-third reported feeling relaxed after inhaling for the first time, and two-thirds of them became addicted to smoking. Overall, 83 of the 217 participants who tried cigarettes became smokers.
Other risk factors for addiction among first-time smokers was depression, a novelty-seeking personality and familiarity with "Joe Camel", the animated character used to advertise the Camel brand, discontinued in 1997.
Among the traits that protected students from becoming addicted were being involved in extracurricular activities. The study was published in Paediatrics, the journal of the American Academy of Paediatrics.
- Reuters
