How can local authorities reduce obesity?
Insights from NIHR research

Local authorities, through their decisions on the local environment, influence what and how we eat, our daily activity, and the success of our efforts to maintain a healthy weight. Local councils told us that the approaches they take must resonate with their local communities and the challenges they face. Even within a local authority, the approach taken in one neighbourhood may need to differ from that in a neighbourhood only a mile away. Many interventions aim to change individual behaviours, but people’s ability to make their own choices is dictated by their circumstances. For example, those with food insecurity who are dependent on food banks, or those living in temporary accommodation, may have limited food choices.

This review draws on the breadth of NIHR research relevant to obesity, conversations with staff at local councils and at national organisations, as well as feedback from a group of practitioners, researchers and members of the public. Together they have helped us identify evidence-based actions that local authorities, working with their local partners, can take to reduce obesity in their communities.

Investing in active travel and increasing access to public transport should be key elements of a systems-wide strategy that aligns with local sustainability and carbon reduction plans. Active travel can encourage people to become more physically active. It has been shown to lower BMI in children, to reduce health inequalities and to provide value for money. Research points to good practice. For example, where walking and cycling paths connect with transport hubs, they are more likely to be used. Encouraging use of public transport can have health benefits for certain groups of the population and goes hand in hand with active travel. Further research is needed to clarify which groups engage with active travel and how it addresses health inequalities.

Changes to the built environment, including access to green spaces, can increase physical activity and improve environmental sustainability. Environments that encourage walking and are close to natural spaces can increase physical activity and have been associated with a lower BMI in children. Investing in environmental design that supports active lifestyles is in line with environmental imperatives. Multiple factors underpin how people use these spaces. Staff at local councils emphasised that some residents rarely leave their locality and therefore will only access green and blue spaces that are in close proximity. Small changes can encourage use of parks, such as removing bushes that obscure the line of sight and can make park users feel unsafe.

Free access to public sport and leisure services can help people to be more physically active, but the picture is mixed over its effectiveness, and whether it reaches those most in need. Programmes to encourage walking can be cost-effective, but findings on community exercise programmes are mixed – studies have not demonstrated sustained physical activity beyond 12 months. The effectiveness of programmes depends on the local area served, the level of deprivation, and the extent of inactivity. The evidence is mixed on whether extending access to public gym and swim facilities reaches those living in disadvantaged neighbourhoods. This will be more relevant for some places than others. Travel to public facilities can also be a key consideration. Behavioural change techniques may be needed to encourage people to use public sport and leisure services; research is needed to find out. In the meantime, local authorities may decide to prioritise investment in infrastructure, the environment and active travel, over public sport and leisure services. Or they may decide that a wider range of solutions is needed that closer align to tackling health inequalities.

Programmes aimed at preventing obesity in children and young people in the community can be effective, but the impact varies across age groups. Few interventions over the last 25 years have targeted the wider determinants of childhood obesity (such as infrastructure, environmental and policy factors). Instead, they have encouraged children to change their individual food and activity behaviours. Cuts to Sure Start children’s centres had an adverse effect on obesity in young children. There are different services in Northern Ireland, Scotland and Wales and the impact of cuts on similar services may vary according to the local context. There is evidence that interventions that include diet or physical activity components, or both, can reduce the risk of obesity in children aged 0 to 12 years and do not worsen health inequalities. However, most studies have reported outcomes at 12 months or earlier, so the long-term effectiveness of these interventions is not known. Young teenagers in particular need approaches that chime with their interests and the importance of friendship groups.

Interventions in schools to increase physical fitness or alter dietary habits have achieved limited results; most NIHR-funded interventions in UK schools have not been effective. Research tells us that leadership and parental and community involvement are likely to support health promotion in schools. Local authority staff emphasised the importance of ‘whole school’ approaches with a wide focus on health promotion beyond just maintaining a healthy weight. Local authorities may consider that attention should be redirected away from interventions focused on changing the behaviours of school children (particularly of primary school age). Instead, they could concentrate on the wider environmental factors that influence behaviour through the lifecourse.

Weight management programmes for people living with overweight or obesity are part of a broader strategy to tackle obesity. Research has shown these programmes may be effective for short-term weight loss. The key question is how long weight loss can be sustained; investing in targeted support to maintain weight loss after a programme has ended has not been shown to be effective. Factors associated with success include: group-based programmes over one-to-one interventions; tailored programmes; and running weight management programmes for children in school settings where attendance is mandatory. More research is needed on the most effective components of weight management programmes. Local authorities told us they are investing in family-based weight management programmes – which have achieved mixed results in NIHR-funded research to date. Barriers found in previous interventions include the costs of participation to families, and sustaining engagement. Addressing these and other barriers could improve the success of programmes.

Local authorities are expected by NICE to be exemplars of workplaces that prevent and manage obesity; however with a move to hybrid working, local authorities may want to direct attention away from office-based workers. NIHR research provided limited support for actions to encourage office workers (including in local councils) to sit less and move more. Local authorities may decide that attention is better directed at creating environments that support active behaviours and reduce calorie consumption across a range of settings, and in incentivising everyone to be active throughout the working day.

Local authorities can take action on the food environment; targeting out of home foods and restricting advertising of high fat, salt and sugar products could reduce excess calorie consumption. Working with food outlets to reformulate recipes and portion sizes, reflecting a ‘health by stealth’ approach, has been well-received by outlets and customers. Further research is needed into how these interventions impact consumption, overall diet, and body weight. Restricting junk food advertising can impact household food purchasing decisions. However, local authorities’ powers to influence advertising vary; decisions to restrict advertising may need to be squared with the loss of lucrative advertising revenue, highlighted by some local council staff. People’s agency and ability to make choices (for example, to eat healthily versus heat their homes), or their dependence on food banks or food pantries, dictate the success of strategies to alter the food environment, local council staff said. Planning guidance to restrict new fast-food outlets near secondary schools has not, as yet, been shown by NIHR research to be effective in decreasing the number of outlets. However, this was possibly due to low numbers of new outlets opening during the study; long term monitoring of exclusion zones around schools are needed. The rise of home food delivery services poses challenges to influencing the food environment, at the same time as allowing new business models to flourish.

More research is needed to assess local authority actions as part of whole system approaches to obesity. The whole system is about bringing together transport planning and spatial planning decisions, education departments, parks and greenspace departments, leisures services, the NHS, integrated care systems, food retailers and more, to work together to reduce obesity. Directors of Public Health have a responsibility to lead a whole system approach to the public’s health across the public sector, within local authorities, and across the NHS and other sectors and agencies, to facilitate system-wide change (Department of Health and Social Care). The research covered by this review has looked at just some of the levers that local authorities can use as part of system approaches. It also highlights some of the enablers and barriers to implementing multi-pronged combinations of interventions, including the importance of leadership, community engagement and having sufficient time and resources to allow initiatives to take effect and demonstrate impact.

The NIHR is continuing to fund research relevant to this agenda. Local authorities can get in touch with NIHR with proposals for research projects, to get support evaluating interventions already in place, or to submit a research suggestion where they have identified a need for more research to help with evidence-based decision making.