SUMMARYOur objectives in this cross-sectional descriptive study were to analyze to what extent freshmen exhibit healthy behaviors, which socio-demographic variables predict healthy or unhealthy lifestyle, and what is the strength of the relationship. Three hundred seven Mexican University students were assessed. t-Test and adjusted multiple regression analysis were computed. Life style was measured by use of the HPLP-II questionnaire and socio-demographics data. The results showed that most students presented a non-healthy lifestyle profile. Overall, the health behavior score was predicted by sex, mother's education and socio-economic level (R 2 ¼ 0.104; p ¼ 0.00001). When controlling for the other variables, nutrition was partially predicted by mother's education (R 2 ¼ 0.048; p ¼ 0.001); physical activity and stress management were modulated by sex, marital status and mother's education (R 2 ¼ 0.111, p , 0.0001; R 2 ¼ 0.096; p ¼ 0.0001, respectively); interpersonal relations were predicted by mother's education and socio-economic level (R 2 ¼ 0.104; p , 0.0001). These influences should be taken into account in designing interventions for specific socio-demographic profiles that might be at higher risk for certain behaviors.