What is a Themed Review?

Themed Reviews are narrative reviews of NIHR-funded research. They provide an overview of existing NIHR evidence, with the aim of illuminating and informing discussions on practice. Themed Reviews are one way for the NIHR to inspire the sharing of research evidence and ideas, and to promote evidence-based practice.

This review identified 143 research studies relevant to local authorities on tackling obesity. A wide array of interventions, settings, and study types were considered; some of the research is in emerging fields. Ongoing research that the NIHR has recently funded is also highlighted, since the upcoming results could help address the current gaps in the evidence base.

The Themed Review drew on the expertise of a group of practitioners, researchers and public members. Additional insight was provided by conversations with a range of staff from local councils and other key stakeholders. Insights from these exchanges provided valuable direction on the context, framing, and sense-making of the review.

Review scope

Projects in the NIHR portfolio relating to obesity and public health were screened. Projects were identified by the NIHR Centre for Business Intelligence (using definitions previously agreed for coding and classification purposes). Supplementary searches for NIHR-funded papers were performed using Dimensions.

The studies included assessed ways to tackle obesity through individual, population, community and environmental interventions, provided they were of potential relevance to local authorities. A broad approach was taken to identifying studies related to obesity. Projects on increasing physical activity or moving more were included even if they were not directly related to weight. Since the review aims to facilitate evidence-based decision making, exploratory, developmental, and early-stage studies were not included.

Studies were grouped into 9 themes, based on the nature of the studies in the portfolio, and to align the review to local authorities’ interests and the aspects they oversee.

Stakeholder Engagement

For this Themed Review, we consulted key stakeholders to understand the context in which NIHR research would be received, and to see how far the evidence reflected experiences within local authorities. We held meetings with groups of staff from the following organisations:

Additional information on graphic and charts

Table of included studies

Area of intervention Number of studies Percentage of total
System-wide approaches 9 6%
Weight management programmes 29 20%
Built and natural environments 12 8%
Active travel and public transport 13 9%
Active workplaces 10 7%
Preventing obesity in children and families 8 6%
Healthy schools 18 13%
Public sports and leisure services 14 10%
What people buy and eat 30 21%

Text alternative for Obesity in the UK graphic

Obesity in the UK

Scotland England Wales Northern Ireland
Percentage of adults with obesity 29% 28% 25% 27%
Percentage of children with obesity 16% 16% 13% 6%
Percentage of adults getting 5-a-day 222% 28% 25% 44%
Percentage of adults meeting physical activity guidelines 46% 61% 53% 36%
Areas of highest obesity Ayrshire and Arran The North East and the West Midlands Cwm Taf Morgannwg and Aneurin Bevan Health Board In the most deprived areas there were 32% of adults with obesity, compared with 25% in the least deprived areas


How we calculate obesity. Body mass index (BMI) is a widely accepted measure for obesity based on weight and height. A BMI of 25 to less than 30 is classified as overweight. A BMI of 30 or more is classified as obese. A BMI of 40 or more is classified as morbidly obese.

Healthy eating guidelines. Guidelines recommend eating at least five portions of fruit or vegetables every day.

Physical activity guidelines. Adults should be active daily, doing 150 minutes of moderate-intensity exercise, 75 minutes of vigorous-intensity exercise, or a combination of both, over a week. Children and young people should take part in physical activity for an average of 60 minutes a day.

References for Obesity in the UK graphic

Information for this infographic was drawn from:
Welsh Government. National survey for Wales: Headline results April 2019-March 2020. 2020.
Public Health Wales. Child Measurement Programme for Wales 2018/19. 2021. (Figures in the infographic apply to children in reception year)
UK Parliament. House of Commons Library. Obesity Statistics. Briefing paper. Number 3336. 2021.
Public Health Wales NHS Trust. Obesity in Wales. 2019.
Department of Health Northern Ireland. Health survey NI trend tables 2019/20. 2020. (Figures relating to children in the infographic apply to those aged 2 – 15)
Department of Health Northern Ireland. ‘A fitter future for all’ – outcome framework (2015-19). 2019.
Department of Health Northern Ireland. Health survey NI first results 2020/21. 2021.
NHS Digital. Health survey for England 2019. Overweight and obesity in adults and children. 2020. (Figures relating to children in the infographic apply to those aged 2 – 15 and take an average of figures for boys and girls)
NHS Digital. National Child Measurement Programme England 2020/21 School Year. 2021.
Sport England. Active Lives adult survey report. May 2020/21. 2021.
OHID. Official Statistics. Physical activity data tool: statistical commentary. 2022.
Sport England. Active lives children and young people survey. Academic year 2020-21. 2021.
NHS Digital. Statistics on Obesity, Physical Activity and Diet, England. 2021.
Scottish Government. Diet and healthy weight: monitoring report 2020. 2020.
Scottish Government. The Scottish Health Survey 2020 edition. 2021. (Figures relating to children in the infographic apply to those aged 2 – 15)
Public Health Scotland. Physical activity overview. 2021.
PHE in association with the Welsh Government, Food Standards Scotland and the Food Standards Agency in Northern Ireland. Eatwell Guide. 2016.
DHSC. UK Chief Medical Officers’ Physical Activity Guidelines. 2019.
Department of Health Northern Ireland. Health survey NI trend tables 2019/20. 2020.