The National Health Survey is a household-based nationwide survey carried out by the Ministry of Health in partnership with the Brazilian Institute of Geography and Statistics. The scope of the survey is to establish the health status and lifestyles of the population - as well as how they look after their health - with regard to access and use of services, preventive actions, continuity of care, and health care financing. The sample size is 80,000 households and enables the calculation of some indicators at different geographic levels, namely states, capitals, metropolitan and rural areas. The questionnaire is divided into three parts. The first two are answered by one resident and include questions on the household characteristics and on the social and economic level and health status of all inhabitants. The individual questionnaire is answered by an adult (aged 18 years or more), selected with equal probability among the adult residents, and focuses on morbidity and lifestyle. For this individual, measurements of weight, height, waist circumference and blood pressure are taken, as well as laboratory exams to characterize the lipid profile and blood glucose level, as well as determine the urine sodium content. The laboratory exams are taken in a subsample of 25% of the census sectors selected.