When adults quit smoking the benefits extend to the next generation. That's the message of a recent study investigating whether adolescent children whose parents were smokers were more likely to start smoking than the children of non−smokers.

If both parents smoked, there was almost a three−fold increase in likelihood their teen would start smoking.

Parents were asked about their smoking habits and lifetime smoking history. Adolescents were asked about their exposure to maternal and paternal cigarette smoking. They were also asked their own smoking history.

Among the 564 adolescents, the prevalence of lifetime cigarette use was 27.8%, ranging from 7.2% among adolescents interviewed at age 12 to an alarming 61.3% among adolescents interviewed at age 17.

When the parental and adolescent information was compared, the researchers found strong evidence for a significant relationship between parental smoking and adolescent smoking. They found that having a smoking parent in the home increases the likelihood that an adolescent will smoke. Interestingly, if the parent used to smoke, but quit, the adolescent's risk of starting smoking was no higher than if the parent didn't smoke at all.

If both parents smoked, there was almost a three−fold increase in likelihood their teen would start smoking. If the father smoked, and lived at home, boys were more likely to initiate smoking. If the father did not live at home, there was no difference from non−smoking male peers. Maternal smoking had an effect on the initiation of smoking in both sons and daughters equally. (This may reflect that mothers are more often the custodial parents.)

The amount of time the parents smoked was significant. The longer they had smoked, the greater the likelihood of teenage initiation. In addition, children who were exposed to parental smoking before the age of thirteen were more likely to smoke than their peers who were exposed later. It made no difference whether the parents were habitual smokers, or nicotine dependent.

The clear message of this study is that adolescents are strongly influenced by parental smoking, and there are a number of specific areas that could be targeted in cessation and abstinence programs for both teens and adults.

The researchers suggest that attitudes, beliefs, and behaviors toward cigarette use are learned through modeling. Therefore, children and adolescents who observe their parents smoking and absorb their experience of a favorable outcome, develop these expectations for themselves over time. Smoking appears to be pleasurable, relaxing, and social and this influences the adolescents' expectations for their own experiences.

It appears that adolescents whose parents quit smoking were also affected by a social learning model, and imitating their parents smoking cessation behaviors and avoiding the negative experiences that they witnessed, but this was not directly analyzed in this study.

When parents are counseled about the impact of their smoking on their children, it can be a powerful tool for helping them change their behavior. Often "doing it for the children" is a stronger motivator than taking care of oneself.

For those counseling teens to abstain from or quit smoking, highlighting the negative aspects of smoking as compared to their parents' apparent pleasurable experience of it may be helpful. Discussions of tobacco's impact on health, physical appearance, and finances, may counterbalance the "positive" messages from their parents' smoking that children have perceived in early adolescence.

The study was published in the February, 2009 issue of Pediatrics.