Smoking contributes to blues among teens

"Smokers who used cigarettes as mood enhancers had higher risks of elevated depressive symptoms than teens who had never smoked," says study co-author Jennifer O'Loughlin,  professor of preventive medicine at the University of Montreal.

As part of the study, 662 high school teenagers completed up to 20 questionnaires from grades 7 to 11 about their use of cigarettes to affect their mood, reports the journal Addictive Behaviours.

Secondary schools were selected to provide a mix of French and English participants, urban and rural schools, and schools located in high, moderate and low socio-economic neighbourhoods, said a Montreal release.

Participants were divided into three groups: never smokers; smokers who did not use cigarettes to self-medicate, improve mood or physical state; smokers who used cigarettes to self-medicate.

Depressive symptoms were measured using a scale that asked how often participants felt too tired to do things; had trouble going to sleep or staying asleep; felt unhappy, sad, or depressed.

The study found that instead of lifting their mood, smoking increased symptoms of depression among teens.