 Over a 5-year period a series of population-based studies are carried out including a total of up to 10,000 persons aged 18-69 years selected from the general population of Copenhagen, Denmark. The study also include a follow-up of a previous population study the Health2006. Participants complete questionnaires on health, lifestyle, and social factors and undergo a health examination including measurements of metabolic biomarkers, allergy tests, anthropometric measures, bioimpedance, biomarkers of micronutrients, spirometry. 