This study investigated whether the effects of self-regulatory cognitions and social influence variables on healthy behaviors - nutrition and physical activity - vary across countries. Adolescents (N = 2387) from Hungary, Poland, Turkey, and the USA participated in the study. Measures included self-efficacy, future orientation, social comparison orientation (SCO), perceived behaviors of peers, as well as age and gender. These variables were included in the path model as predictors of healthy behaviors. The role of a country as a moderator was also examined. Results showed that self-efficacy, SCO, and perceived behaviors of peers predicted both health-promoting behaviors in all four countries. Some differences were found regarding the role of future orientation and gender.