Within NANS dietary, demographic and phenotypic data was collected from a Nationally representative sample within Ireland from 2008-10. The fieldwork phase was carried out between October 2008 and April 2010. Adults aged 18-90 years (740 males, 760 females) were recruited in the Republic of Ireland. Eligible respondents were adults aged 18 years and over who were free-living and who were not pregnant or breast feeding. A sample of adults was randomly selected from a database of names and addresses held by Data Ireland (An Post). An introductory letter and information leaflet were posted to each person selected from the database. A researcher called to potential respondents‟ homes to introduce the survey and invite participation. If the individual agreed to participate, a consent form was signed and the survey commenced. If the person was not at home, the researcher called on three more occasions on different days and at different times, before deeming them ineligible. For groups that were not highly represented in the database, particularly 18-35 year olds, a second level of recruitment was introduced. A second database of names and addresses was compiled through referrals from respondents and participation was invited for those that were contactable.