Nutrition, Gut Microbiota and Health : Feces Sample Collection in NutriNet-Santé Participants

The gut microbiota is currently attracting increasing attention from the scientific community and also from the general public, as evidence of its role in human physiology has been highlighted. Microbial signatures have also been associated with various pathologies (e.g. obesity, diabetes, gastrointestinal disorders, neurodegenerative diseases), but the causality of these associations is still uncertain. Among the factors that may influence the composition of the gut microbiota (e.g. lifestyle, hygiene, medication, genetics, environment), nutrition would a major role. The major changes in lifestyle and diet observed over recent decades are strongly suspected of disrpting the host-gut microbiota balance. In addition to their nutrient content, our diets also contain other bioactive compounds (e.g. polyphenols) and raise new issues (e.g. temporal structure of diets, food processing, presence of additives or contaminants such as pesticide residues, intake of dietary supplements, dietary exclusions, glycemic index) that is necessary to take into account. Thus, it is mandatory to explore and characterize in a more precise way, within large samples consisting of individuals with varied characteristics, the way in which the composition of the gut microbiota is influenced by the host's diet and its health consequences. The aim of this research is therefore to study the links between nutrition, gut microbiota profiles and health. To do this, the research will implement large-scale stool sample collection from participants in the NutriNet-Santé cohort ("Nutrinautes"), thus constituting a "microbiota" sub-cohort. A target of N=10,000 participants in the NutriNet-Santé cohort will be recruited on a voluntary basis. A selection will then be made among Nutrinautes willing to participate in the research (which may be more numerous than necessary) to maximize the diversity of profiles. Participants will be informed of their selection or non-selection by e-mail. A second stool sam