If a teen's first cigarette is a relaxing experience, he or she is more likely to become addicted to smoking.

Researchers from the University of Massachusetts Medical School recently completed a four-year study of 1246 sixth-graders to find out why some teenagers get addicted to cigarettes and others do not.

"It is how the brain reacts to nicotine, rather than personality traits," according to Dr. Joseph DiFranza, lead author of the study.

The study appears in the Journal of Pediatrics.

Labels: brain_chemistry, cigarettes, smoking