tobacco use and substance abuse in students of karaj universities

background: it is clear that tobacco smoking and substance abuse have negative consequences on adolescent and youth’s health. tobacco smoking especially hookah smoking has increased worldwide especially among university students. this study aimed to determine the prevalence of risk‑taking behaviors such as cigarette smoking, hookah smoking, alcohol use, and drug abuse and its predictors in students of karaj universities. methods: this cross‑sectional study took place in karaj in january and february 2014. the randomly selected sample consisted of 1959 college students. a self‑administered questionnaire was used to measure risk‑taking behaviors as well as demographic and related risk factors. logistic regression model was performed in data analysis. results: the prevalence of cigarette smoking was 9.3%. the prevalence of hookah smoking was 9.3%. 7% of students used illegal drugs and 9.5% of students used alcohol at least once in last 30 days. after adjustment for other factors, being male, living without parents, having smoker friends, and presence any smoker in the family were factors associated with students’ risk‑taking behaviors. the results showed the co‑occurrence of risk‑taking behaviors. conclusions: the prevalence of tobacco smoking and substance abuse, particular in males, are high. it seems that planning preventive interventions for this part of the population are necessary. this study emphasized the co‑occurrence of risky behaviors, so, it is better high‑risk behaviors simultaneously targeted at reducing or preventing interventions.