Introduction:
Smoking is the greatest determinant of public health problems. In Chile, the rate of smoking in individuals between 17 and 24 years is 55%. As medical students advance in their studies, their knowledge of smoking as a determinant of disease increases. Nevertheless, students from more advanced class levels smoke more than those of lower levels. Objective: Determine the prevalence of smoking and the attitude towards quitting in medical and engineering students, in their first and fourth years of studies at the University of Chile. Material and method: Cross sectional descriptive study. A self-administered survey was used, recording demographic variables, smoking behavior, and attitude towards quitting. Results: The sample consisted of 490 students (28.6% women). The prevalence of smoking was 18.6% (17.9% in women and 18.9% in men, p=ns). Among medical students, the prevalence of smoking was 21.4%; among engineering students it was 16.6% (p<0.01). In both areas the first year students had a similar rate (18.2% in medical students and 16.8% in engineering, p=ns). This rate was maintained in fourth year engineering students (16.3%), but increased significantly in fourth year medical students (24.3%). Medical students have a more dynamic attitude towards their smoking habit than engineering students. The pattern of tobacco behavior in women is potentially more harmful than in men. Discussion: Medical knowledge of the harmful effects of tobacco doesn't play a role in decreasing the rates of smoking. It is necessary to promote preventive activities related to the consumption of tobacco in medical schools.