OBJECTIVE: The decrease in mortality due to cardiovascular diseases (CVD) has been achieved in the United States and the same decrease has been happening in developing countries, thanks to favorable changes in lifestyle and risk factors. Despite such consideration, the volume of information available on the distribution and behavior of that type of disease and its risk factors in Brazil is still little. METHODS: The assessment of changes in total cholesterol (TC), levels of blood pressure (BP), body mass index (BMI) and smoking was carried out, besides the occurrence of fatal (F) and non-fatal (NF) cardiovascular events, under dietary and behavioral intervention and long-term follow-up (up to 20 years) in a closed group, consisting of 621 electric power company workers of both sexes, with average age of 29.1±7.1 years old, varying from 15 to 59 years old. Actuarial curves were obtained to analyze the F and NF cardiovascular events. RESULTS: The TC mean showed significant reduction due to dietary guidance. The smoking habit decreased significantly with behavioral changes. The mean of the BPs decreased significantly with a better detection and hygienic measures, and the adhesion by definite hypertensive people to the treatment showed an index of 56.6%. On the other hand, the BMI showed an expressive and gradual increase. The probability for the individuals to remain free of any cardiovascular event was of 98.1%, whereas for the fatal events, it was 99.2%. CONCLUSION: Those results prove that initiatives directed towards the prevention must be priorities, aiming at modifying the morbimortatility rates of CVD.