A new study released in the publication Tobacco Control, says that smoking only one cigarette can lead to cravings three or more years later. This "sleeper effect" causes the urges to lie dormant until the appropriate trigger comes along.
The researchers claim that the nicotine from just one cigarette can change the reward pathway in the brain. Others say much of it has to do with breaking down social barriers teens come against with smoking.
The survey was conducted in London area schools, where students ages 11 to 16 were questioned. 14% of 11-year-olds admitted to experimenting with cigarettes in 2004. This group was found to be twice as likely to take up smoking by age 14.