Health literacy (HL) is a topic of increasing importance todays' ever-changing world. Over the past few decades, HL has gained importance, as it is a factor related to health behaviors and outcomes. In Portugal, the last survey was in 2016 and 61% of the population had a problematic or inadequate level of HL in general. Lisa is a cohort study that will measure HL in the adult population residing in the municipality of Leiria over the next 4 years, with measurements every 2 years. Over the years we will promote activities and interventions adjusted to the needs of Leiria's population. At the end we want to understand the changes during the years and improve the health care provided.