How can local authorities reduce obesity?: Insights from NIHR research

Introduction

‘Obesity is considered to be one of the most serious public health challenges of the 21st century. It is having an impact on people’s lives now, across the generations, in terms of our quality of life, our risk of developing chronic diseases such as type 2 diabetes and its association with common mental health disorders. 

Doing nothing is not an option. Without action, the health of individuals will continue to suffer, health inequalities associated with obesity will remain and the economic and social costs will increase to unsustainable levels’ 

Local Government Association. 

The NIHR invests more than £1bn a year in research to improve the health and wellbeing of the nation. Over the last decade, we have invested heavily in research aimed at preventing or managing obesity. We want to support good local decision making by ensuring that investment decisions can be based on sound evidence. This will maximise the impact of stretched local resources. 

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

The Themed Review drew on the expertise of a group of practitioners, researchers and members of the public. Conversations with a range of local authority staff and other key stakeholders gave us valuable insights. They helped us draw the research together in a meaningful way, put it in context and made sure the Review addressed key questions. 

The interventions covered by NIHR research were specific to local contexts and may not always be applicable elsewhere. For example, local councils told us that certain food advertising restrictions on the London Underground, which demonstrated impact in London, would be harder to achieve in their local context. In addition, studies generally ran for 12 months or less; some interventions could take much longer to show an impact. 

This Review covers 143 NIHR-funded studies, of which 32 were underway when the Review was completed. The chart below shows how many studies were funded across different areas of obesity research.

You can find a table version of the data contained in this chart in the appendix.

Context

Obesity is a major health crisis in the UK (Department of Health and Social Care) and more than a quarter of adults are living with the condition. 

Obesity in the UK

A text alternative for this prevalence graphic can be found here, and the references used to produce this graphic can be found here

Consuming more calories than are needed leads to weight gain. Boys living with obesity or overweight, for example, have been found to consume between 140-500 excess calories each day (UK Health Security Agency). Globally, there has been an increased intake of energy-dense foods that are high in fat and sugars (World Health Organisation), and UK consumers generally do not meet the standards recommended for a healthy diet (Rand). However, many factors drive obesity; there is no single dominant cause.

Early life experiences - including growth patterns in the first weeks or months of life - affect the risk of obesity years later (Foresight). Children of parents living with obesity are more likely to develop obesity themselves. And by the end of primary school, 35% of children are living with overweight or obesity (UK Parliament). 

The NHS spent an estimated £6.1 billion on overweight and obesity-related ill-health in 2014 to 2015 and these costs are expected to reach £9.7 billion by 2050 (Public Health England). The costs to the wider economy include higher levels of sickness and absence from work, and have been predicted to reach £49.9 billion per year by 2050 (Foresight).

Local authorities face a mass of competing pressures. They have to respond to rising care needs, tackle health inequalities, and reach net zero. They have to maximise childrens’ life chances and build back local economies after the pandemic. Obesity has an impact on many of these priorities. It drives up care needs, has an adverse impact on life chances and reduces economic productivity. By contrast, strategies to reduce obesity can have a positive impact on the environment and progress towards net zero. For example, more active travel, by foot or bicycle, can also reduce road traffic.

The COVID-19 pandemic has brought the obesity crisis into sharp relief. People living with obesity have an increased risk of severe illness and death from COVID-19 (Public Health England). The pandemic has also widened the health inequalities associated with race, gender and where we live (Local Government Association). Children living in the most deprived areas in England are more than twice as likely to live with obesity than those living in the least deprived (NHS Digital). People living in the most deprived areas are less likely to meet ‘5 a day’ guidelines for fruit and vegetable intake, or to meet physical activity guidelines (Department of Health and Social Care); young people from the least affluent families tend to be the least active (Sport England). Eating a healthy diet relies on people having consistent access to nutritious food (food security). In the UK, food and non-alcoholic drink is the fourth largest household expense (Department for Environment Food and Rural Affairs). When household income is stretched, choice of food is likely to be limited by its cost, and the ability to eat a healthy diet is threatened. Tackling obesity therefore goes hand in hand with the levelling up agenda. In its response to this agenda, the Local Government Association stresses the need to reduce poor health outcomes (including obesity) as well as economic imbalances between regions (Local Government Association). 

The need for a whole systems approach to tackle obesity - comprising national policy, multinational actions on food and retail, together with local initiatives - is increasingly recognised. Local authorities can directly support aspects of this approach (Public Health England). At a local level, a systems approach moves away from a series of isolated interventions. Instead, it seeks to understand the system as a whole, and the interventions that represent powerful levers for change. Stakeholders from across the local systems need to collaborate for this approach to be possible. Activities where a council can take action need to be identified (for example, natural spaces, travel infrastructure, or the local food environment). And systems thinking, which can help make sense of a complex situation by looking at the relationships between different parts (rather than considering each separately) will be needed to generate dynamic and flexible interventions (Local Government Association).

Some NIHR funded research seeks to alter people’s behaviour directly (e.g. through education to promote a healthy diet). Other projects adapt the environments in which we live, work and play to support people to be active and eat healthily. The research may be for people living with obesity, or may aim to prevent obesity in the broader population. Several interventions aim to increase physical activity. However, the link between increased activity and obesity is not clear cut. Physical activity on its own is unlikely to prevent obesity, but, as part of a wider package of initiatives, can help achieve change. Most research to date has evaluated specific, single interventions, and there has been less on combinations of interventions that address multiple aspects of the system. 

In this Review, we cover areas in which local authorities can take action: 

• Influencing what people buy and eat 
• Encouraging healthy schools  
• Expanding access to public sports and leisure services
• Promoting active workplaces
• Providing weight-management programmes
• Designing built and natural environments
• Enabling active travel and public transport
• Preventing obesity in children and families 
• Embracing system-wide approaches

We draw conclusions to help local authorities make sense of the research, and use it to inform decision-making.   

Influencing what people buy and eat 

What this section covers

This section covers NIHR funded research into the impact of the environments in which people buy, prepare, and consume food. These food environments shape what we eat. Our current food environment is dominated by unhealthy ‘junk’ foods (energy dense, and high in saturated fat, sugar and salt) (The National Food Strategy). Local authorities can influence food environments, and reduce health inequalities. ‘Healthier zones’ and ‘school superzones’, for example, limit the number of fast food outlets and advertising of unhealthy food in areas with many outlets, high levels of deprivation, or where children gather (UK Health Security Agency). Local authorities also enforce food standards regulations, including labelling.  

What’s the context?

• The food environment can undermine efforts at weight management.(1) Easy access to unhealthy food and drink, from takeaways for example, and prominent displays of unhealthy foods, such as of sweets at supermarket checkouts, drive the consumption of unhealthy foods and obesity. (2) People who are socially and economically disadvantaged, and some minority ethnic groups, are especially vulnerable (Foresight, The National Food Strategy).
• Meals at cafes, restaurants and from takeaways (out of home meals) are contributing to rising levels of obesity. These meals tend to contain more energy (with higher levels of fat, saturated fats, sugar, and salt), and lower levels of micronutrients. There are more fast food outlets in deprived areas, on average, than in more affluent areas (Public Health England). Online fast food outlets in England are also more accessible in the most deprived areas.(3)
• National policies aim to tackle obesity by altering the food environment. Efforts include a soft drinks industry levy (HM Treasury), and reducing sugar in the products children eat most (Public Health England). Sugar content declined in large UK chain restaurant menu items between 2018 and 2020 (possibly in response to these measures) but there was little change in salt and saturated fat.(4) 
• New initiatives include calorie labelling on menus in large food businesses including restaurants, cafes and takeaways (Department of Health and Social Care). Restrictions on the placement and promotion of food and drink high in fat, salt and sugar (HFSS) will come into force in October 2022. From January 2023, advertising of HFSS products will also be restricted. (Department Health Social Care).
• Some local authorities choose which companies can advertise in bus shelters; others pass control of bus shelters to a third party. Local authorities can influence the position of billboards via the planning system, but generally not what is advertised on them. There have been calls for greater local controls to restrict junk food advertising where it is at odds with local health priorities (Food Active and Sustain). 
• Local authorities are responsible for enforcing the new requirement for calorie labelling on menus (Department of Health and Social Care). Existing measures on food labelling in shops have been shown to increase knowledge about the nutritional value of food,(5) reduce the purchase of HFSS foods,(6) and may stimulate product manufacturers to reformulate recipes (The National Food Strategy).

What does NIHR research tell us?

The wider environment, age, gender and socioeconomic status all influence food consumption 

People living on low incomes can find it hard to eat healthily.(1) Healthier foods tend to cost more, and there are many deals on HFSS foods.(9) Better access to healthy food outlets (specialty stores such as greengrocers) at home and at school is associated with better dietary quality in young children.(7) People of higher socioeconomic status, older people, women and those not working overtime are more likely to eat home-cooked meals and not rely on out of home food.(8) 

Interventions that require people to understand and act upon information (high agency) tend to be less effective than those that do not rely as much on individual decision-making (low agency). High agency interventions include food labelling or financial incentives that require effort from consumers (e.g. cash back incentives).(10) Low agency interventions include making healthy food cheap, available and accessible. 

Targeting out of home food could reduce excess calorie consumption 

Local authorities commonly give awards to food outlets that meet certain criteria (recipe reformulation, adding healthier options or smaller portions to the menu) to promote healthier eating. Outlet owners have been generally positive about such interventions, especially when they are cost neutral and use a ‘health by stealth’ approach. That means imperceptible changes to price, taste, or portion size. Customers are generally in favour of these changes and are often unaware they have happened. Further research is needed into the effectiveness of the interventions.(12) 

Policies regulating the content of out of home food (e.g. levels of fat, salt or sugar) could influence what people eat. A modelling study suggested that policies to reduce fat content in this food could reduce obesity. A reduction of 20% in fat content could reduce the prevalence of obesity by 5.3%, and of overweight by 1.5%.(11)

Planning guidance to restrict new fast food outlets near secondary schools was not effective in decreasing the number of outlets at 3 years. This was possibly due to the low numbers of new outlets in the study area.(13)

Restricting food advertising can be particularly effective for those in the most disadvantaged communities

Several types of advertising (for food delivery services, digital advertising, and adverts in recreational environments) have been associated with increased obesity in adults. Exposure to advertising for HFSS food and drink is unequal across society. Younger adults, and those in lower socioeconomic groups are most likely to report having seen advertising of processed HFSS foods, sugary cereals and sweet snacks.(14)

Exposure to screen advertising (on TV, and in video games) for unhealthy food significantly increases children’s dietary intake.(15) Young children (aged 8 years or less) are especially vulnerable, and children from low socioeconomic and minority ethnic backgrounds are most exposed to this advertising.(16) Using celebrities or cartoon characters to market HFSS foods, has been found in laboratory-based studies to increase children’s preferences for these products (17), and to increase their consumption.(18) Modelling research has predicted that restricting advertising of unhealthy food and drinks between 05:30 and 21:00 could reduce childhood obesity by two-thirds, and help tackle health inequalities.(19)

Restrictions on HFSS advertising have also been shown to influence adults. Removing HFSS advertising on public transport networks in London in 2019 was followed by reductions in average weekly household purchases of HFSS foods.(20) Challenges in implementing restrictions included defining ‘junk food’, developing policy that complies with existing legal frameworks, taking account of the uneven impact of the policy on different industry stakeholders (due to differences in company size and product ranges), and balancing health and financial effects. Close communication with industry helped, along with an exceptions process to consider products (e.g. cough sweets) that might not contribute to children's HFSS consumption.(21)

Useful resources

• The Eatwell Guide provides a framework for government recommendations on eating healthily and achieving a balanced diet (Public Health England, 2016). 
• The Local Government Association together with national government and Public Health England, has produced a toolkit to help local authorities and businesses provide and promote healthier options for food eaten away from home, including the management of new business applications and working with existing food outlets to provide healthier food. 
• The government has also outlined ways in which local authorities can help businesses offer healthier food and drink, including planning policies to promote healthier diets, and restrictions on new hot food takeaway outlets.
• A healthier future: Scotland’s diet and healthy weight delivery plan sets out the vision for a partnership to support everyone to eat well and have a healthy weight.   

NIHR research in progress 

• How does living in a lower income community impact children’s responses to efforts to help them eat a healthy diet? (22) What impact do Universal Infant Free Schools Meals have on the diet of low-income infants? (23) How effective is a scheme in which households in areas of deprivation receive £5 weekly vouchers (along with recipes and healthy eating advice) to spend on fresh fruit and vegetables?(24)
• What impact do online food ordering and delivery services have on different demographics, and health inequalities?(25)
• What impact do fast-food exclusion zones have at scale? This research is using a dataset of all food outlets in England.(26)
• What impact does mandatory calorie labelling in the out-of-home food sector have, and how effectively is it enforced?(27)
• Interactions between local governments in England and harmful industries (large companies that sell unhealthy products) are being explored. This research aims to develop principles to inform local decision-making. (28) Other research is evaluating policies to improve the food environment, including mandatory, voluntary, and partnership approaches.(29)
• Local policies to support restrictions on outdoor advertising for HFSS foods in council-owned spaces are being explored.(30)

Encouraging healthy schools

What this section covers

Schools can be environments that encourage healthy behaviours; they can help children establish habits of healthy eating and being physically active. This section covers NIHR-funded research into interventions that aim to prevent obesity in schools, and are open to broader groups of children, for example entire year groups. Interventions targeting children living with obesity are covered under ‘Providing weight management programmes’; interventions in the community are covered under ‘Preventing obesity in children and families’.

What’s the context?

• Rates of obesity in children double in the 7 years between entering primary school and starting secondary school (NHS Digital), and increase further in secondary school (HM Government).
• National commitments include: updating food standards for schools to reduce sugar consumption; reviewing how the least active children are being engaged in physical activity in and around the school day; and a national ambition for every primary school to adopt an active mile initiative (HM Government).
• Opportunities for local authority actions include: working with headteachers and governors to adopt a whole school approach in implementing policies and practices to support healthy weight, food and the promotion of physical activity; creating a culture of healthy eating; offering a breakfast club where at least 40% of pupils in areas of deprivation are eligible for free school meals; and promoting safe modes of active travel to and from school and college (Public Health England). 

What does NIHR research tell us? 

The Daily Mile in primary schools increases activity and may lead to small reductions in BMI

The Daily Mile has been implemented widely in primary schools in disadvantaged urban areas where children are most likely to be living with obesity, and have fewer opportunities for physical activity.(2,3) It had a small (non-significant) effect on body weight (BMI z-score), with a greater effect in girls. The Daily Mile may be cost-effective as part of a system-wide approach to obesity prevention; longer-term follow up is needed.(1) 

Other primary school interventions have little effect on physical activity and diet

Interventions in UK primary schools have not been shown to be effective or cost-effective in preventing overweight or obesity (4,5). They include: helping teachers to provide 30 minutes’ additional physical activity; running school-based healthy cooking workshops for parents and children; providing information for families. A gardening intervention was not effective at increasing fruit and vegetable intake.(6) One intervention for children aged 9 to 10 years included teacher training and materials for teachers, children and parents. It did not increase levels of physical activity, reduce sedentary behaviour or increase fruit and vegetable intake. However, it may have had other benefits, such as reducing screen viewing at weekends at home, and the consumption of snacks and high-energy drinks.(7)

School-based interventions in primary schools are unlikely to have a major impact on promoting healthy levels of physical activity and healthy diets. But some children may benefit. The greatest effects are seen in girls, older primary school children, and those whose parents have higher education.(8)

Interventions in UK secondary schools have not increased physical activity

Interventions to increase physical activity in secondary schools tend to involve pupils acting as peer leaders to promote physical activity. These interventions have not been shown to increase levels of moderate to vigorous physical activity (9–11) or to counter the age-related decline in physical activity.(12) Interventions may not have been sufficiently intense, or reached those most in need: a dance-based programme appealed to those who were already active.(11)

A whole school ‘health promotion’ ethos is facilitated by leadership, parent, and local community support

Health promotion in schools is enabled by a headteacher with a health-promoting ethos and a proactive leadership team;(13) parental involvement;(14) and pathways between schools and local communities that reinforce physical activity messages. (13–15) 

Barriers include a lack of government support and regulation; school structures and organisation; staff capacity; canteens run by businesses; a lack of family and community engagement; a lack of student involvement; financial constraints; a focus on educational outcomes and school performance. (13,15,16) 

Useful resources

• Government guidance on what works in schools and colleges to promote levels of activity among children and young people. 
• The National Institute for Health and Care Excellence (NICE) provides guidance on whole-school approaches and recommends long-term programmes, with multiple components, including after-school clubs and other activities. 
• NHS Scotland’s overview of evidence found that food and drink policies are most effective when they address the whole food environment; adaptations (such as reducing fat content, age-appropriate portion sizes and limiting unhealthy options) could reduce obesity.
• Ofsted has recommended that schools and parents need to reinforce each other’s roles more effectively. 
• The Local Government Association gives examples of public health teams working with local schools, many of them academies, to promote activity and healthy nutrition. Examples include  ‘Fruity Fridays’ when PE kits are worn, pupils are encouraged to be active during the whole day, and there is a health-themed assembly. 

NIHR research in progress

• How to engage teenagers in a programme to promote healthy diets and physical activity. (17)
• How effective is an environmental nutrition and physical activity programme for children aged 2 to 4 in nurseries?(18)

Expanding access to public sports and leisure services 

What this section covers

This section covers NIHR funded research into efforts to increase physical activity through public sports and leisure services. Facilities range from multi-function leisure centres and sports clubs, to swimming pools and outdoor activities. They are owned by local councils, and often operated by other organisations or community trusts. NIHR research also looked at community programmes, such as exercise classes and to encourage walking. 

What’s the context?

• Many people in the UK are not meeting physical activity guidelines, particularly in deprived areas. Local authorities are expected to promote physical activity in their local communities as part of obesity prevention (NICE). 
• The more deprived an area is, the more dependent people are on public sports and leisure provision (Local Government Association). 
• The COVID-19 pandemic has disrupted people’s ability to exercise, particularly children and young people (Sport England). It disrupted public sport and leisure services, which lost income during long periods of closure (Local Government Association). The future of leisure centres needs to be secured to tackle the growing obesity crisis (District Councils’ Network). 
• There have been calls to unlock the potential of fitness and leisure facilities to serve more people through social prescribing (UKactive). 

What does NIHR research tell us? 

Free access to leisure facilities can help people to be more physically active 

Free access to leisure facilities can increase participation in swim and gym activities,(1,2) by removing financial barriers and providing an incentive to use facilities.(3) However, the evidence on the benefits to those most in need is mixed. Some research has found that removing charges increases use among more disadvantaged groups.(1,4) For example, free holiday swims for children have been shown to increase the numbers of swimmers in deprived areas, and could reduce inequalities in physical activity.(4) But other research found that it may not be sufficient to encourage inactive adults and those living in disadvantaged neighbourhoods to take up regular exercise.(2) 

Walking programmes can be a cost-effective way to increase physical activity 

A programme to promote walking in adults (aged 45 to 75) involved a pedometer, walking plan, tips on how to change behaviour, and support via nurse consultations (for one group). It increased step count and weekly activity levels in both groups, and these changes were sustained at 3 years. The group without nurse support offered best value for money.(5)  

There is little evidence that community programmes lead to sustained physical activity 

Overall, research on the effectiveness of community exercise programmes is mixed - studies have not demonstrated an effect beyond 12 months. One study gave plans to encourage walking to people aged 65+, along with weekly home or class-based exercise. At 12 months, classes held in the community centre were more successful in increasing physical activity than home exercise classes.(8) Another study offered a range of physical activities to people of all ages living in rural villages. This led to a slight increase in minutes of moderate-to-vigorous intensity activity per week but did not increase the likelihood of meeting physical activity guidelines.(9) In a middle-aged population (40 to 64 years) from a deprived area, motivational interviews to sustain increased physical activity (by telephone or face to face) did not influence activity levels. The ‘booster’ intervention was unlikely to be clinically- or cost-effective; further research is needed on how to sustain physical activity.(10)

Factors that can help or hinder community programmes have been explored among adults in mid-to-late life. Poor awareness of community-based programmes is a barrier to people over 55.(6) People aged 40 to 64 were encouraged to attend by: enjoyment, social support, and tailored programmes. Addressing affordability helped people living in deprived areas.(6,7) 

Useful resources 

• The Association for Public Service Excellence, the Local Government Association and Chief Cultural and Leisure Officers Association have proposed a rethink of what local communities will need from leisure facilities and services in the future. New, more efficient and impactful solutions need to be designed to help communities to be active and stay healthier for longer. They consulted over 250 local councils and the report contains examples of initiatives by councils and leisure services. 
• Sport England has been testing approaches to using sport and physical activity to tackle obesity. It has shared a resource to approaches, models and tools that can be adapted to local needs. 
• NICE guidance advises that local authorities should have senior physical activity champions to raise the profile of physical activity and to develop local initiatives with members of the community. 

NIHR research in progress

• Several studies are looking at physical activity among older adults. In Northern Ireland, a peer-led walking programme for inactive adults (60+) in disadvantaged areas is being investigated.(11) Another peer-led programme is for adults at risk of mobility disability (65+), in England and Wales.(12) A third study is evaluating weekly exercise classes in preventing mobility-related disability in retired people (65+).(13)
• How effective is ‘snacktivity’ - an activity snack of 2-5-minutes (such as walking while on the phone)? (14) 

Expanding access to public sports and leisure services 

What this section covers

This section covers NIHR funded research into efforts to increase physical activity through public sports and leisure services. Facilities range from multi-function leisure centres and sports clubs, to swimming pools and outdoor activities. They are owned by local councils, and often operated by other organisations or community trusts. NIHR research also looked at community programmes, such as exercise classes and to encourage walking. 

What’s the context?

• Many people in the UK are not meeting physical activity guidelines, particularly in deprived areas. Local authorities are expected to promote physical activity in their local communities as part of obesity prevention (NICE). 
• The more deprived an area is, the more dependent people are on public sports and leisure provision (Local Government Association). 
• The COVID-19 pandemic has disrupted people’s ability to exercise, particularly children and young people (Sport England). It disrupted public sport and leisure services, which lost income during long periods of closure (Local Government Association). The future of leisure centres needs to be secured to tackle the growing obesity crisis (District Councils’ Network). 
• There have been calls to unlock the potential of fitness and leisure facilities to serve more people through social prescribing (UKactive). 

What does NIHR research tell us? 

Free access to leisure facilities can help people to be more physically active 

Free access to leisure facilities can increase participation in swim and gym activities,(1,2) by removing financial barriers and providing an incentive to use facilities.(3) However, the evidence on the benefits to those most in need is mixed. Some research has found that removing charges increases use among more disadvantaged groups.(1,4) For example, free holiday swims for children have been shown to increase the numbers of swimmers in deprived areas, and could reduce inequalities in physical activity.(4) But other research found that it may not be sufficient to encourage inactive adults and those living in disadvantaged neighbourhoods to take up regular exercise.(2) 

Walking programmes can be a cost-effective way to increase physical activity 

A programme to promote walking in adults (aged 45 to 75) involved a pedometer, walking plan, tips on how to change behaviour, and support via nurse consultations (for one group). It increased step count and weekly activity levels in both groups, and these changes were sustained at 3 years. The group without nurse support offered best value for money.(5)  

There is little evidence that community programmes lead to sustained physical activity 

Overall, research on the effectiveness of community exercise programmes is mixed - studies have not demonstrated an effect beyond 12 months. One study gave plans to encourage walking to people aged 65+, along with weekly home or class-based exercise. At 12 months, classes held in the community centre were more successful in increasing physical activity than home exercise classes.(8) Another study offered a range of physical activities to people of all ages living in rural villages. This led to a slight increase in minutes of moderate-to-vigorous intensity activity per week but did not increase the likelihood of meeting physical activity guidelines.(9) In a middle-aged population (40 to 64 years) from a deprived area, motivational interviews to sustain increased physical activity (by telephone or face to face) did not influence activity levels. The ‘booster’ intervention was unlikely to be clinically- or cost-effective; further research is needed on how to sustain physical activity.(10)

Factors that can help or hinder community programmes have been explored among adults in mid-to-late life. Poor awareness of community-based programmes is a barrier to people over 55.(6) People aged 40 to 64 were encouraged to attend by: enjoyment, social support, and tailored programmes. Addressing affordability helped people living in deprived areas.(6,7) 

Useful resources 

• The Association for Public Service Excellence, the Local Government Association and Chief Cultural and Leisure Officers Association have proposed a rethink of what local communities will need from leisure facilities and services in the future. New, more efficient and impactful solutions need to be designed to help communities to be active and stay healthier for longer. They consulted over 250 local councils and the report contains examples of initiatives by councils and leisure services. 
• Sport England has been testing approaches to using sport and physical activity to tackle obesity. It has shared a resource to approaches, models and tools that can be adapted to local needs. 
• NICE guidance advises that local authorities should have senior physical activity champions to raise the profile of physical activity and to develop local initiatives with members of the community. 

NIHR research in progress

• Several studies are looking at physical activity among older adults. In Northern Ireland, a peer-led walking programme for inactive adults (60+) in disadvantaged areas is being investigated.(11) Another peer-led programme is for adults at risk of mobility disability (65+), in England and Wales.(12) A third study is evaluating weekly exercise classes in preventing mobility-related disability in retired people (65+).(13)
• How effective is ‘snacktivity’ - an activity snack of 2-5-minutes (such as walking while on the phone)? (14) 

Providing weight management programmes for people living with obesity 
What this section covers

This section covers NIHR funded research into the impact of weight management programmes in adults and children. Weight management programmes are for people living with overweight or obesity and aim to reduce a person’s energy intake and help them to be more physically active by changing their behaviour. Programmes should last for at least 12 weeks, with weekly or fortnightly sessions, including regular weigh-ins. People can self-refer, or be referred by a health or social care practitioner. Programmes, courses and clubs take place in the community, workplaces, primary care, online, and in other settings (NICE). 

What’s the context? 

• NICE recommends weight management programmes with multiple components for adults living with overweight or obesity, as part of an integrated approach to preventing and managing obesity (NICE PH53). The programmes should include behaviour change strategies to increase physical activity levels or decrease inactivity, improve eating behaviour and the quality of diet, and reduce energy intake (NICE CG189). 
• NICE also recommends and provides guidance on how to deliver effective weight management programmes for children and young people (NICE PH47) 
• Government funding has prioritised weight management services, with the aim of helping people to adopt healthier behaviours, lose weight and improve their general wellbeing (Department of Health and Social Care). During the COVID-19 pandemic, more services were delivered remotely or online. 
• Most councils (98%) have accepted additional new funding to expand provision. This can be face to face, remotely or online (Department of Health and Social Care). 
• Further funding has been allocated to 11 local authorities to help expand child weight management services and improve access for up to 6,000 children living with excess weight or obesity (Department of Health and Social Care). 

What does NIHR research tell us?

Weight management programmes in adults can be effective for short-term weight loss 

Weight management programmes can help adults to lose weight. This has been shown in men (1,2), those living in areas with above average deprivation, and from a range of ethnic backgrounds.(3) Benefits can extend beyond weight loss, to include improvements in diet and physical activity, self-esteem and mental health.(2) Weight management programmes are cost-effective compared to taking no action. (2,4) However, surgical treatments are more cost-effective than weight-management programmes.(4) During pregnancy, weight management programmes can reduce the amount of weight gained. (5–7) But, they are not cost-effective (6) and may do little to prevent gestational diabetes or reduce the risk of large-for-gestational-age babies.(8)

The most effective components of weight management programmes 

Very low-calorie diets and low energy total diet replacement (e.g., soups, shakes and bars) can lead to weight loss that lasts 1 to 3 years.(4,9,10) The evidence is mixed on the cost-effectiveness of these diets. (4,11) Total diet replacements are unacceptable to people in some ethnic groups, who prefer low-calorie food tailored to their culture.(12) Weight reduction for men has been shown to be best achieved and maintained with the combination of a reducing diet, physical activity advice or a physical activity programme, and behaviour change techniques.(13) Dietary interventions are the most effective approach for reducing weight gain in women during pregnancy.(5)

Group-based weight management programmes with a social element are more effective

Group interventions have been shown to be more effective in terms of weight loss at 12 months than one-to-one interventions.(14) (NIHR Alert) Men respond to programmes delivered in social settings (13) and enjoy group-based interactions and feeling part of a team.(1,2)

Evidence on sustaining weight loss is mixed 

Weight loss following a weight management programme tends to be measured after 2 years or less.(15) Some research has shown weight loss can persist for 4 years or more,(2,10,13), but other research has shown that weight loss is not sustained at 4 years (16) or longer.(17) Greater initial weight loss from weight management programmes can lead to faster weight regain, but weight may still be reduced at 5 years or more.(15)

Support to maintain weight loss has not been effective 

Programmes that aim to maintain weight loss have not been shown to reduce weight regain. However, keeping weight loss programmes available to participants after they have lost weight is associated with a slower regain in weight.(15) Telephone support (18) and SMS-text messaging support (19,20) were not effective at weight maintenance after a weight management programme ended. 

Family-based interventions for children with obesity have met with mixed results 

Several family-based interventions for children who were living with overweight or obesity (aged 6 to 18 years) focused on parenting and lifestyle education. These interventions did not lead to weight loss or behaviour change. (21–23) Issues included: low uptake, the costs to families of participation (including higher quality food, time and transport costs), and little long-term change in weight or physical activity. (22) Another programme involved twice-weekly physical activity sessions (in sports centres and schools) as well as education. The 9-week programme was followed by a 12-week free family swimming pass. This programme reduced BMI z-score at 12 months, and had a positive effect on cardiovascular fitness, physical activity, sedentary behaviours and self-esteem. A key strength was the acceptability of this programme to families; average attendance was 86%. (24)

Weight management programmes for children are more successful in schools than in community settings 

Weight management programmes to treat obesity in children aged 4 to 16 were slightly but significantly more effective in schools than in community settings (e.g., leisure centres or community halls). The intervention comprised 10 weekly sessions on topics delivered by health coaches. In the school setting, there was a small but significant reduction in BMI z-score for participants above a healthy weight. There was no overall impact on weight in the community setting. Looking at sub-groups across both programmes, the programme had greater effect for children of Black (African/Carribean/Other) ethnicity, those over age 11 and those from the most deprived groups. All the children in schools completed the intervention, however, in community settings, only 33% did so. The school programme included participants regardless of weight and attendance was mandatory. The community programme only included children above a healthy weight and had a ‘drop-in’ design.(25) 

Interventions in schools that are not targeted towards children with obesity, and focus instead on preventing obesity, are covered under ‘Encouraging healthy schools’. 

Useful resources

• The Department of Health and Social Care offers leaflets, posters and resource packs for adult weight management programmes run by local authorities.
• NICE offers a range of tools and resources to support weight management programmes. 
• NHS Inform, Scotland’s national health information service, offers an online weight management programme, with online activity trackers, meal planners and weekly journals. 
• Livewell comprises 13 Essex local authorities and other partners, and provides details of adult and child weight management programmes. 
• Government guidance on evidence-based behaviour change techniques for family weight management services. 

NIHR research in progress

• Which weight management approaches are most effective in producing weight loss, and best suited to different groups of people? (26) 
• How weight management programmes can be scaled up, including the cost-effectiveness of using non-specialists (such as health trainers and community members) and technology (web and telephone).(27) 
• How can technology be harnessed to deliver weight management interventions?(28)

Designing built and natural environments

What this section covers

This section covers NIHR funded research into the impact of the built and natural environment (including green and blue space) on obesity. The built and natural environment refers to the physical environment in which people live, work and play (Public Health England). The built environment includes neighbourhood design, housing and transport. Green space includes parks, woodland, fields, and allotments (Public Health England). Blue spaces are outdoor water environments, natural or manmade, including rivers, lakes and the sea (Environment Agency). 

What’s the context?

• The quality of the local environment contributes to activity levels and (excess) calorie consumption in daily life. Planning and designing the environment can help address obesity at the same time as contributing to environmental and sustainability goals (Public Health England).
• Local authorities can protect, maintain and improve local spaces - and create new open spaces - to help everyone move more without the need for direct, costly interventions (NICE). 
• Equitable access to green and blue space are critical for maintaining and supporting health and wellbeing in local communities. Local authorities are asked to prioritise improved access to green space and to create greener communities, especially in areas of deprivation, as part of reducing health inequalities. They are advised to establish interventions, such as green social prescribing initiatives, that will encourage people to use green space, and promote individual and population health (Public Health England). 
• A cross-government project is testing how to embed green social prescribing into communities in order to improve people’s mental health, reduce health inequalities, reduce demand on the health and social care system, and develop best practice in green social activities (NHS England). 

What does NIHR research tell us?

Access to parks and the built environment affect rates of childhood obesity

Traffic-related air pollution and the absence of local parks are associated with higher levels of childhood obesity; the presence of parks is associated with decreased levels of childhood obesity. The number of intersections in an area (which indicates how easy it is to walk through an area) is also associated with obesity.(1) In studies around the world, proximity to green and blue spaces has been associated with increased physical activity, active travel, or reduced BMI in children.(2)  

Exposure to green and blue spaces may increase physical activity and wellbeing 

Living near green and blue spaces has been associated with health benefits, such as reduced risk of cardiovascular disease.(3) Other research has not found a clear association between health and  exposure to green and blue spaces.(4) Improving footpaths, vegetation and community engagement, intended to increase the use of woodland in deprived areas, did increase physical activity levels. However, the increase in visits to natural spaces was low and no improvements were found in health or quality of life.(5) In other work, participation in environmental activities, such as nature conservation and litter picking, enhanced a sense of wellbeing. (6) More research is needed to show the long term impact on obesity.(4,6)

Major road expansion reduces physical activity and may increase health inequalities

Research has shown that major road expansions (i.e., new motorways) can reduce physical activity, promote car use and may increase health inequalities.(7) Traffic calming measures to create 20mph zones can reduce road accidents, but to date there is insufficient evidence of their impact on health outcomes, such as physical activity.(8)  

Urban regeneration projects have not reduced obesity

Urban regeneration projects related to the London 2012 Olympics have so far shown only modest or temporary improvements in physical activity, and no beneficial effects on obesity.(9,10) This is despite improved access to sporting facilities and green space, and accommodation specifically designed for active living. 

Useful resources

• The UK Government's 25 year plan to manage and improve the environment. 
• Natural England’s green infrastructure mapping database provides technical evidence on the green infrastructure in England. 
• Public Health England has published a review on improving access to greenspace, including the role of local authorities. 
• Public Health England has published a resource for planning and designing healthier places. 
• NICE quality standard (QS183) encourages local authorities to involve  community members in designing and managing public open spaces. 

NIHR research in progress 

• What effect have 20mph speed limits in Edinburgh and Belfast had on health?(11) 
• What impact have Ultra Low Emission Zones (areas where polluting vehicles must pay a levy in order to use the roads) had in London?(12)

Enabling active travel and public transport

What this section covers

This section covers NIHR funded research into the impact of active travel and public transport on physical activity and maintaining a healthy weight. Active travel means making everyday journeys in physically active ways, such as by walking or cycling, instead of using cars, motorbikes or other motorised transport (Public Health England). Public transport is often linked to active travel, since people walk or cycle to access it.  

What’s the context?

• The growth in road transport has contributed to reducing physical activity and increasing obesity. Switching more journeys to active travel promises to improve health, quality of life, the environment, air pollution, and local productivity, as well as reduce costs to the public purse (Public Health England).  
• Many people in the UK are not meeting physical activity guidelines, particularly in deprived areas. Walking or cycling as part of a daily routine is one of the most effective ways to increase physical activity (Public Health England). 
• The COVID-19 pandemic created a national ‘moment of change’ to promote cycling and walking (Department for Transport). In 2020, the number of people cycling on public highways was higher than any year since the 1960s (Minister of State for Transport). A drive to cement these behaviours underpinned the government’s vision for cycling and walking (Department for Transport). New working patterns, with a move to hybrid working, may present different challenges and opportunities for active travel.  

What does NIHR research tell us? 

Active travel (walking or cycling) to school can lower children’s BMI

A study tracked more than 8,000 schoolchildren for several years and found that those who switched to walking and cycling to school between the ages of 7 and 14 had healthier body weights than those who continued to travel by car. This was seen particularly in children from the most deprived areas.(1)(NIHR Alert) 

Improved walking and cycling paths increase active travel, particularly when they connect to transport hubs 

Improving the quality and quantity of walking and cycling paths can increase active travel and the number of people meeting physical activity guidelines. New walking routes encouraged less active people to take up walking for transport,(2) reduced health inequalities, and provided value for money.(3)(NIHR Alert) The greatest uptake of active travel was on routes: near public transport hubs; where walking and cycling use was low; in areas of deprivation and high population density.(3) Routes were more likely to be successful when accessibility and connectivity (convenience) were taken into account.(4) For example, people living close to a new bus network and traffic-free pedestrian and cycle paths were more likely to increase their active travel and cycling time, and decrease their car trips. This is compared to people living further from the bus route. People who were less active originally were most likely to change their behaviour and increase their active travel.(5)

Improving safety and the experience of cycling and walking influences the use of routes

Successful programmes to promote walking and cycling address the issues of traffic and personal safety, and improve the experience of walking or cycling.(4) For example, a new or improved bridge or tunnel can increase the use of walking or cycling paths in deprived areas. These features may not appeal to everyone; the number of women cyclists was less likely to increase where there were bridges or tunnels, possibly because these features reduce natural surveillance and feelings of safety.(3) 

School cycle training does not increase the likelihood of cycling in adolescence 

Offering cycle training in primary school has not been found to increase the likelihood of cycling in adolescence (13 to 15 years). Cycling has been found to be more common among teenage boys than girls, in rural areas, and in areas with higher levels of adult cycling.(6)

Encouraging the use of public transport can support a healthy weight and increase physical activity 

Use of public transport is associated with a lower BMI in adults,(7) and switching from private car to public transport for school journeys has been associated with lower percentage body fat in children.(1) Free bus passes for people over 60, (8) including those from minority ethnic groups (9) can promote active travel. But free bus travel for young people (12 to 17 years) in London did not significantly increase active travel. However, teens reported wider benefits, such as more independent travel and social inclusion.(10)

Useful resources   

• Public Health England has published a guide of practical actions for local authorities to promote active travel. 
• The Department of Transport has produced guidance for local authorities on promoting an active return to work. 
• Active Travel Info is funded by the Department of Transport and provides information to help local authorities build a business case for investment.
• NICE quality standard (QS183) encourages local authorities to prioritise pedestrians, cyclists and people who use public transport when developing and maintaining connected travel routes.
• NICE public health guideline (PH41) encourages people to walk or cycle more, either for travel or recreation.
• The Department for Transport set out the government’s current cycling and walking plan.
• Sport England offers tools and resources to support active travel.  

NIHR research in progress

• How does new walking and cycling infrastructure support a shift to active travel among commuters and older adults in market towns? (11)
• Do new low traffic neighbourhoods increase active travel? (12) 
• What impact did emergency travel schemes have on active travel and social distancing during the COVID-19 pandemic? The schemes included pedestrianised high streets, new cycle lanes, low traffic neighbourhoods and the temporary closure of roads outside schools. The research will inform decisions over whether to make the schemes permanent. (13)   

Embracing system-wide approaches to support healthy weight 

What this section covers

Public Health England and the Local Government Association have stated that a ‘whole systems approach’ to obesity is an example of a ‘health in all policies’ approach. This means that tackling obesity is a priority for the whole local authority, not just for public health departments. Local authorities need to lead their communities and local partners, working with local NHS organisations and through integrated care systems. This section covers NIHR funded research into specific or multi-pronged actions that local authorities could take at local level within a whole systems approach.

What’s the context?

• For local authorities, a ‘whole systems approach’ to obesity means using all the assets of the local area, supporting a community-centred approach to tackling health inequalities, and developing transferable workforce skills and capacity (Public Health England and the Local Government Association).  
• Preventing obesity through planning and development is one lever. It relies on systems policies that join up actions from health and planning perspectives (LGA and Town and Country Planning Association). Local authorities can shape the design of environments and what they provide, in ways that support people to avoid overweight or obesity.
• The Town and Country Planning Association and Public Health England have set out the elements necessary to help achieve healthy weight environments through planning. These are: movement and access (promoting active travel and physical activity); open spaces, recreation and play; food retail and growing food; neighbourhood spaces (community facilities and public spaces); the design of homes and other buildings to promote healthier living; local economy (employment and healthy town centres or high streets).

What does NIHR research tell us?

Research into system-wide approaches is still in its infancy 

One review included 33 studies which had aimed to implement a whole systems approach. Approaches were defined as those ‘that consider the multifactorial drivers of overweight and obesity, involve transformative co-ordinated action across a broad range of disciplines and stakeholders, operate across all levels of governance and throughout the life course’. A range of positive health outcomes were reported, including: health behaviours; reducing BMI; parental and community awareness; nutrition; physical activity environments. The researchers concluded that the approaches showed promise. But they said that the evidence on how to implement systems approaches to address public health problems is still in its infancy, and further research is needed. Consistent definitions and language relating to obesity systems approaches is essential.(1)    

The review identified features of successful approaches. These included: the full engagement of relevant partners and community; time to build relationships, trust and capacity; good governance; finance; and embedding the systems approach within broader policy.(1)    

Whole town approaches by local authorities rely on leadership, national level support, community engagement and sufficient resource 

A programme aiming to stimulate novel ‘whole town’ approaches to obesity (the Healthy Communities Challenge Fund, also known as the ‘Healthy Towns’ programme) was successful in generating a diverse set of interventions. They covered: physical activity, active travel, growing (e.g. vegetable growing), urban planning, and other one‐off initiatives or co‐ordinating activities. Systems approaches were regarded as a promising solution to tackle obesity, but a wide range of enabling and disabling factors influenced each town’s ability to implement them. Enabling factors included: engagement with local stakeholders; identifying leaders within each town; and funding to maintain and develop interventions. 

Barriers included: leads having limited time to develop as systems‐thinkers; tight timeframes in which to take a more strategic approach; and a lack of national level support. Individual interventions were often delivered in isolation, which reduced the connections across programmes and the synergies between interventions. Despite a mandate to be innovative, towns felt under pressure from stakeholders to demonstrate positive results, leading them to revert to ‘tried‐and‐tested’ interventions that had a higher chance of success, rather than testing truly innovative interventions that had a higher risk of failure.(2)

Local communities can identify multi-pronged approaches specific to local challenges 

Affordability of healthy food, of sports and physical activities (such as football clubs and swimming), and of transport was an issue for young people in one town considering systems-wide approaches to obesity. Suggestions for addressing obesity included: cultivating a healthy environment in the town by banning cars in the town centre; regulating the advertising of unhealthy foods; and taking a community and school-based approach, such as raising awareness of local sports clubs and more education on healthy eating and obesity.(3)

Mass media campaigns may support systems-approaches 

Research has explored the impact of mass media campaigns (television, radio, social media, newspapers) on health topics such as diet, activity, smoking and alcohol. There is little evidence regarding behaviour change following diet campaigns, but media campaigns may reduce sedentary behaviour. Media campaigns increased knowledge and awareness across several topics, including diet, and influenced intentions to increase physical activity. Longer, intensive campaigns, targeted at particular populations with specific messages, were more likely to be effective.(4) The UK’s Change4Life campaign to promote healthy lifestyles, and associated diet-related campaigns (e.g., 5 a day, Sugar Swaps), reached the population: approximately 1 in 5 of the people surveyed were aware of government healthy eating campaigns, with greater awareness among people with higher versus lower educational level.(5) Further research is needed to understand whether this increased awareness translated into health benefits. 

Useful resources

• The Association of Directors of Public Health (ADPH) and Public Health England (PHE) have co-produced a series of ‘What Good Looks Like’ (WGLL) publications including ‘What Good Healthy Weight for all ages Looks Like’. They are intended to facilitate the collective efforts of local organisations and wider society (the system) towards improvements in their population health outcomes. 
• Public Health England signposts a range of supporting frameworks, resources and tools for addressing health inequalities. This is part of a briefing on how partners can work together to systematically address health inequalities and identify the components of a cross-system and place-based approach.
• Public Health Wales has produced a blueprint for local authorities to use to help create healthy weight environments.
• The Town and Country Planning Association has published lessons from ‘planning healthy weight environments’ workshops for local councils, in particular, councillors, and those working in planning and environment teams, and in public health.

NIHR research in progress

• Will the intervention, Together An Active Future, increase physical activity levels in 6 districts of Lancashire? Different approaches will be tried in each district to identify which are most successful in increasing physical activity.(6)
• Two research projects in Scotland are assessing systems approaches. A community pilot project in East Scotland is taking a whole systems approach to diet and healthy weight.(7) Another project, in two council areas in Tayside, is seeking to apply learning from a whole systems approach (‘Healthy Weight Tayside’) in Dundee City.(8) 
• What impact do obesity policies have in various sectors: retail, the environment, transport, education and the workplace? This research aims to develop methods to measure value-for-money to support decisions on how to spend limited funds.(9)

Conclusions 

Obesity is the result of interplay between many factors (Foresight). The context in which local authorities operate - levels of deprivation, resources, urban and rural geography, and other competing priorities locally - influences the approaches that can be taken to prevent obesity. National initiatives, such as taxes or other regulatory changes, are important. Supporting people to maintain a healthy weight requires action on many levels: individual, organisational, across whole systems, local and national. 

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 public members. 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, infrastructure, community sport and physical activity

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.  

Influencing behaviour from childhood 

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. 

Supporting people living with obesity

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. 

Strategies that reflect societal shifts, e.g. in the workplace

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. 

Reducing excess calorie consumption

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.     

Local actions to support system-wide approaches

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.   

Appendices 

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 [x-ref]. 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:

• ADEPT (Association of Directors of Environment, Economy, Planning and Transport)
• COSLA
• Hertfordshire County Council
• Local Government Association
• Portsmouth City Council
• South Gloucestershire Council
• South Tyneside Council
• Wigan Council

Additional information on graphic and charts

Table alternative for pie chart

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 prevalence 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	22%	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

Definitions

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.

NIHR Evidence is covered by the creative commons, CC-BY licence. Written content and infographics may be freely reproduced provided that suitable acknowledgement is made. Note, this licence excludes comments and images made by third parties, audiovisual content, and linked content on other websites.

• Share via:
•