National Diet and Nutrition Survey 2019 to 2023

About the study

The National Diet and Nutrition Survey (NDNS) is designed to assess the diet, nutrient intake and nutritional status of the general UK population. Participants aged 18 months and over living in private households are selected each year from all 4 UK countries. The sample is designed to be nationally representative.  The survey results are used by UK governments to monitor progress toward diet and nutrition objectives and to develop food and nutrition policies.

Methodology

NDNS is a cross-sectional survey (that is data collected from participants at a single point in time), designed to be representative of the UK population. NDNS was impacted by the COVID-19 pandemic, and from March 2020 the survey methodology and protocols had to be adapted in line with government advice and regulations.

The survey aims to collect data from a UK representative core sample of 1,000 people per year: 500 adults (aged 19 years and over) and 500 children (aged 18 months to 18 years). Additional addresses were selected in Northern Ireland (NI) to increase the NI sample size and enable comparisons to be made with the UK as a whole.

From each selected household, the interviewer randomly selected up to 1 adult and 1 child, or 2 children from different age groups, to take part in the survey. The survey was carried out in 2 stages. The first stage was a Computer Assisted Personal Interview (CAPI) with each participant, carried out by the interviewer. 24-hour dietary recalls were completed using an online dietary assessment method, Intake24. The first recall was completed on the day of the interview. Participants received the invitation to complete their next dietary recall by text or email 2 to 6 days (randomly allocated) after completion of their previous dietary recall.