It has been well established that some of the risk factors for coronary heart disease are related to lifestyle,that is,behaviors that are potentially modifiable.In order to test the daily stress state in our subjects (a number of 518 medical students,aged 20 ± 2 years)we used Perceived Stress Questionnaire, which pointed out the occurrence of stress in 73.8 ± 21% of girls and 54.5 ± 18% of boys (p<0.05).A non fasting lipid level profile (total cholesterol, HDL cholesterol, LDL cholesterol and triglycerides)was measured by venous-puncture.In the primary analysis, HDL was the criterion variable,while the percentage of dietary fat, physical activity,sedentary behaviour, smoking, genetic predisposition,and stress were the predictor variables. The present study asses the relationship between stress and HDL levels.In this study,the number of daily life events(positive and negative) was significant in predicting HDL levels among the total sample of young adults. Regression analyses revealed differences between girls and boys. For girls,the percentage of daily life events contributed significantly to the variation in HDL levels.