According to a large number of news articles reporting on a new study appearing in this month's issue of Tobacco Control, smoking just one cigarette is enough to addict kids to smoking.
For example, Web MD leads its story on this study with the headline:
"1 Cigarette May Hook Teens on Smoking."
Medical News Today (UK) opens its article on the study with the headline:
"Compulsion to Smoke After Just One Cigarette Can Lie Dormant for More than Three Years."
ITV Network Limited (UK) led with the headline:
"One Cigarette Means Three-Year Cravings."
The Scotsman reported that:
"Just One Cigarette as a Child is Enough to Spark Teen Addiction."
The Guardian (UK) stated that:
"Just One Cigarette in Childhood Can Lead to Later Addiction, Says Study."
The Rest of the Story
Actually, what the study showed is that smoking a single cigarette is not addictive. The study found that less than half of seventh-grade students who had smoked one cigarette went on to become smokers in the next two years. And a large percentage of students who smoked one cigarette by grade 7 and later started smoking did not start smoking for a period of two to three years (see: Fidler JA, Wardle J, Henning Brodersen N, Jarvis MJ, West R. Vulnerability to smoking after trying a single cigarette can lie dormant for three years or more. Tobacco Control 2006; 15:205-209).
So in fact, what the study found was that a single cigarette does not have some sort of powerful addictive potential, such that a person is hooked immediately upon smoking that cigarette. Many kids who tried smoking a cigarette did not in fact become addicted to smoking from that cigarette, and even among those who did eventually become addicted, it was apparently not the first cigarette that caused the addiction because they were able to abstain from smoking for years (not a pattern that is characteristic of someone who is addicted to smoking).
The interpretation of the study results to imply those who started smoking years after trying their first cigarette did so because of some sort of physical dependence caused by that first cigarette is quite extreme.
But what seems more extreme is the need to try to explain why having experimented with smoking puts a youth at subsequent risk of smoking. After all, you can't become a smoker unless you have experimented with smoking. You can't smoke 100 cigarettes unless you've first smoked 1 cigarette, no? So it should be no surprise to anyone that kids who experiment with smoking are more likely to become smokers. It has to be that way.
It's like arguing that someone who gets married is more likely to reach a 10-year anniversary than someone who does not get married. You can't reach the 10-mile mark without first reaching the 1-year mark, and you can't even get there without first reaching the status of a newlywed.
The contribution of this paper to the literature is not that it demonstrates that experimentation with cigarettes is a risk factor for becoming a regular smoker (which we have known for years and pretty much has to be the case). The contribution of the paper is that it documents that the process of smoking initiation is one which can take place gradually over a number of years and that the process is not necessarily a steady one; a youth can try smoking, then not smoke for a long time, and then still go on to become a smoker.
But should we conclude, as our first hypothesis to explain this phemomenon, that the reason these youths resume smoking after several years is that the first (and only) cigarette had a powerful addictive effect that somehow lied dormant for years?
I think not. Isn't it more likely that the factors which lead someone to experiment with smoking are also factors which may lead to progression from experimentation to regular smoking? Or that factors which lead someone to experiment with smoking are correlated with factors that cause progression from experimentation to regular smoking?
We in fact know that some factors associated with smoking experimentation are also associated with progression from experimentation to established smoking. For example, peer smoking has been demonstrated to influence both trying cigarettes for the first time and progressing from trying cigarettes to using them regularly.
We also know that some factors associated with smoking experimentation are correlated with factors that lead from progression to regular smoking. For example, parental smoking is strongly associated with trying cigarettes for the first time. And strong parental disapproval of smoking is associated with progression from experimentation to regular smoking. And parental smoking is negatively correlated with strong parental disapproval of smoking.
So there are many reasons why a youth who tries smoking is more likely to later smoke regularly, without having to rely on the far-fetched conclusion that trying a single cigarette causes one to become hooked on cigarettes, that smoking a single cigarette is powerfully addictive, but that the addiction lies in dormancy for years before it finally surfaces.
Why did the media get this story so wrong? I don't know. The study itself certainly did not conclude that trying a single cigarette causes addiction that lies dormant for years. In fact, the authors acknowledge that environmental or personal risk factors for smoking may explain the observed results, suggesting that "Changes in the environment are likely to trigger a repeated experience with cigarettes among those vulnerable -- for example, through changing protective and risk factors such as peer smoking, stress, depression, religiosity and school environment," and that "The personal traits that lead to early experience of smoking could contribute an underlying increase in risk of smoking that is not triggered until environmental conditions are right."
Of course, the authors did also suggest that perhaps a neurobiological change might be caused by smoking a single cigarette that lasts for years and that this could explain a "dormant effect" of smoking a single cigarette: "From a neurobiological viewpoint, neural reward pathways might be changed as a consequence of a single exposure to nicotine, thus potentially increasing vulnerability to later smoking uptake." Perhaps it was this statement or something similar stated in an interview that led the media down this path.
Whatever the reason, the rest of the story is that you cannot and should not always believe everything you read in the media, especially in reports on health-related scientific articles published in scientific journals.
Even when we are accurate in how we depict the science, the media may still get it wrong and end up misleading the public. This makes it even more essential that we are accurate in how we depict the science.