Most teenagers who smoke cigarettes make repeated attempts to quit but most are unsuccessful, according to new research from the Université de Montréal and funded by the Canadian Cancer Society.

"The study found that teen smokers make their first serious attempt to quit after only two and a half months of smoking, and by the time they have smoked for 21 months they have lost confidence in their ability to quit," says Dr. Jennifer O'Loughlin, the study's lead author and a researcher from the Université de Montréal's department of social and preventive medicine.

Dr. O'Loughlin analyzed data from 319 Montreal teens who completed reports on their smoking habits every three months for five years. The study found that teen smokers progress through stages or milestones in their attempts to stop smoking. These stages are:

Confidently declaring that they have stopped smoking forever, one to two months after their first puff;

Expressing a conscious desire to quit with a growing realization that quitting requires serious effort;

Over the next two years, as cravings and withdrawal symptoms increase, gradually losing confidence in their ability to quit;

A year later, they are smoking daily and now realize they still smoke because it is very hard to quit;

About two years after starting to smoke cigarettes daily, teen smokers are showing full-blown tobacco dependence.

The study found that more than 70 percent of the teens expressed a desire to quit, but only 19 percent actually managed to stop smoking for 12 months or more by the end of the five-year study. Girls were more likely than boys to want to quit and to attempt quitting.

"These findings indicate that teenagers want to quit smoking," says Dr. O'Loughlin. "We really need to develop and implement effective tobacco control interventions for young people, before it's too late."

Participants were aged 12 to 13 at the beginning of the study. For these novice smokers it took about:

Nine months after their first puff to become monthly smokers;

19 months after their first puff to become weekly smokers;

23 months after their first puff to become daily smokers.

"These findings show that teen smokers want to quit and attempt to quit, but very few are actually able to stop for long periods" says Rob Cunningham, senior policy analyst, Canadian Cancer Society. "This research suggests that much more needs to be done to prompt teenagers to quit in terms of programming, legislation and taxation. In particular, federal and provincial governments must get the contraband situation under control -- cheap cigarettes discourage teen smokers from quitting. "

This research was funded by the Canadian Cancer Society.