Background Smoking is one of the major risk factors for various diseases. There is some evidence that smoking is associated with mental health problems.

Objective To evaluate the association among mental health problems and smoking in teenagers at 15 years old in a population-based birth cohort.

Methods 4325 adolescents from the 1993 birth cohort, from the city of Pelotas, southern Brazil, were examined. Smoking was defined as to have smoked one or more cigarettes in the previous 30 days. Mental health was assessed according to the total score of the questionnaire Strengths and Difficulties Questionnaire being considered as positive when the score was ≥20 points. Data were analysed using Poisson regression with adjustment for robust variance.

Results Smoking prevalence was 6.0% and about 30% of the adolescents presented any problem related to mental health. In the crude analysis, the prevalence ratio to present mental health problem was 3.3 (95% CI 2.5 to 4.2) and after the adjusted analysis (for sex, age, skin colour, family income, maternal education, smoking among friends, employment in the last year, school failure, physical activity at leisure and experimental use of alcohol) it decreased to 1.9 (95% CI 1.2 to 2.3) among smokers compared to non-smokers.

Conclusion We concluded that mental health problems in adolescence may be related to tobacco consumption.