Objective: To understand the influence of work conditions in the health of Colombian nursing personnel, especially regarding the work shifts in Antioquia.Methods: We performed a cross-sectional study on a sample of 365 nurses, men and women between 18 and 58 years old, with more than one year of experience in the profession, who performed night shifts in the last quarter and who work for public or private institutions of 39 municipalities of Antioquia's health department.We found an indicator of 5% error and 98% confidence.Performing self-directed questionnaire scales and 21 semi-structured interviews.Descriptive statistic calculations were performed and statistical chi-square test was applied.Results: We found that working conditions especially related to work shifts have a high influence on the health status of Colombian nurses in the territory of Antioquia, in comparison with other countries; working conditions are precarious, especially in the amount of working hours.Conclusions: We conclude that working conditions detract the health conditions of nurses, so recommendations on how to reduce this influence are necessary.