Epidemiologists use various methods to track lifestyle diseases, including: - Surveillance systems: To monitor the incidence and prevalence of diseases. - Cohort studies: Following a group of individuals over time to observe how lifestyle factors affect health outcomes. - Case-control studies: Comparing individuals with a disease to those without to identify potential risk factors. - Cross-sectional studies: Analyzing data from a population at a single point in time to assess the burden of lifestyle diseases.