INSERM-UMS 011 (Population-Based Epidemiological Cohorts Unit) is a joint unit of INSERM and Versailles Saint Quantin University (UVSQ). UMS 011 is managing two large population-based cohorts: Gazel and Constances. Gazel is composed of 20 000 subjects aged 35-50 at inception in 1989, 25 years ago; all were working in the national utility company at that time and are retired now. Constances is a representative sample of 200 000 persons of the French adult population aged 18-69 at inception; recruitment began in 2012 and will be completed in 2017. In both cohorts, numerous data useful for the project were prospectively collected and are available for research. UMS 011 is involved in several European research consortia (Integrated Datasets in Europe for Ageing Research – IDEAR; BBMRI-Large-scale Prospective Cohorts).