In the study, researchers surveyed almost 6,000 London teens between the ages of 11 and 16 about their cigarette use. Additionally, each child had their saliva analyzed for signs of nicotine use.
In 2004, 14 percent of 11-year-olds stated that they had experimented with cigarettes. But even those who had stopped after one cigarette were twice as likely to have become a regular smoker by the time they were 14-years-old. For these teens, the gap between the first cigarette and the second was more than three years.
The researchers state that this lag time between cigarettes shows that there is a "sleeper effect" when it comes to cigarette use. Even one smoke can change how the brain perceives rewards, so a teen may seek out a cigarette for relief when later experiencing the stress of depression. Additionally, the authors suggest that crossing the line by smoking just one cigarette, makes it easier for a teen to smoke again in the future without worrying as much about how their parents will react or how they will look in front of peers.
Regardless of why the affect of just one cigarette can linger, the researchers believe their work may help prevent today's kids from becoming tomorrow's smokers.
"It may be that preventing children from trying even one cigarette is an important goal, and prevention efforts could be focused at the earliest ages," they write.