MRC Elsie Widdowson Laboratory

National Diet and Nutrition Survey

The National Diet and Nutrition Survey Rolling Programme (NDNS RP) is designed to assess the dietary habits and nutritional status of adults and children in the UK. The survey is unique as it provides the only source of high quality data on dietary intakes and nutritional status in a representative sample of the population. The survey is funded by UK government health departments and is carried out by MRC Elsie Widdowson Laboratory (MRC EWL) jointly with NatCen Social Research (NatCen). MRC EWL provide the scientific lead and all nutritional components for the NDNS RP.

The NDNS programme began in 1992, and each cross sectional survey focused on a different age group, e.g. preschool children (1.5 to 4.5 years) or adults aged 65 years and over. Since 2008 the NDNS has run continuously covering both adults and children. This has enabled more rapid data collection and greater ability to track temporal changes and to respond more quickly to changing policy needs. The NDNS RP is currently in the second funding phase: 2012 – 2018, fieldwork years 6-10.

A minimum of 500 adults and 500 children are recruited. A total of between 1000 (core sample) and 1500 (boost sample) individuals, aged 18 months and above, are sampled from England, Wales, Scotland and Northern Ireland per year. As such, the NDNS RP gathers detailed quantitative and qualitative information on the dietary habits and nutritional status of a representative sample of the UK population.

The results of the NDNS RP are used to assess the adequacy of food and nutrient intake and nutritional status in different population groups. They are also used by government to develop policy and monitor progress on diet and nutrition objectives, such as work to move the public towards a healthier diet or tackling obesity. Food consumption data is also used by the Food Standards Agency (FSA) to assess exposure to chemicals in food, this informs risk assessments and the setting of regulatory limits for contaminants.

Survey contents

All survey components are carried out in the participant’s home. The survey is carried out in two stages, comprising an interview visit followed by a nurse visit generally conducted around 8 – 12 weeks later.

The NDNS interview collects data on

  • Demographic and socio-economic characteristics
  • Dietary habits, food and nutrient intake and population trends in food consumption
  • Physical activity
  • Oral health
  • General health and lifestyle, including smoking and alcohol consumption
  • A spot urine sample for iodine status assessment

Food intake data is collected using an estimated (unweighed) 4-day food diary. Participants are offered opportunity to receive feedback about their diet after completion of the nurse visit.

The nurse visit includes:

  • anthropometric measurements
  • blood pressure measurement
  • blood sample collection for laboratory analysis for nutritional, routine metabolic and cardio-vascular status assessment

Clinical relevant results are reported back to the respondents themselves and/or their GP as requested on consent to participation.

The NDNS RP is carried out under National Research Ethics Service (NRES) Research Ethics Committee (REC) approval.

MRC EWL’s role for the NDNS RP

The MRC EWL provides the scientific lead for the NDNS RP. The survey is delivered in collaboration with NatCen who take responsibility for sampling and fieldwork. For NDNS RP Years 1 to 5 (2008/09 – 2012/13) the consortium included the Surveys Team at UCL.

MRC EWL specific Responsibilities to the NDNS RP are as follows:

The success of the NDNS RP depends on the good will and voluntary cooperation of members of the public across the UK. The survey is also reliant on the support of regional NHS and private laboratories for the provision of blood specimen processing and storage. In addition, specialist laboratories at Addenbrookes Hospital and the Centres for Disease Control and Prevention in the US undertake specific analytical measures outside the MRC EWL repertoire.

MRC EWL conducts additional investigations to explore the NDNS dataset in more detail to address issues of strategic importance for our research or on behalf of our collaborators. This may include the analysis of the diet or nutritional status of specific subgroups, examining the relationship between specific nutrients or foods on health outcomes and modelling the impact of reformulation or wider dietary change on the nation’s health.

NDNS Reports and Data

Links to the latest NDNS reports can be found on the UK Government ,  FSA Scotland, Welsh Government and FSA in Northern Ireland websites. Earlier reports can be found in the National Archives. NDNS data can be accessed from the UK Data Archive.

UK Sodium (Salt) Surveys

The UK Sodium Surveys, funded by UK health departments, provide an assessment of dietary salt intake through the analysis of the sodium content of 24h urine samples collected from a representative sample of adults aged 19 to 64 years. These surveys are integral to the government’s public health surveillance programme. MRC EWL inputs include logistics support and fieldworker training for sample collection, laboratory analyses, results analysis, and interpretation and reporting.

With our partner NatCen we recently conducted the Sodium Surveys for England and Scotland (2014/15) and Northern Ireland (2015). These resulted in separate reports on sodium intakes for adults aged 19 to 64 years in England, Scotland and Northern Ireland published in 2016.

Past sodium surveys:

*Tables in these surveys have been adjusted and presented in Appendix E of the 2014 Sodium Survey for England