Obesity and inequalities

The Covid-19 pandemic and subsequent national lockdowns illustrate both the structural weaknesses and adaptability of the food system. Of note is how the pandemic exposed systemic reliance upon emergency food aid and food charities amongst members of vulnerable communities^{(Reference Eskandari, Lake and Butler14)}. However, societal reliance upon food banks/food parcel deliveries to meet chronic food insecurity needs has subsequently raised political controversy: actors across food policy networks highlight how food charity masks the economic unsustainability of this approach^{(Reference Caraher and Davison15)}, how it normalises food insecurity, and fails to tackle the root causes of poverty^{(Reference May, Williams and Cloke16)}. Moreover, the unpredictable just-in-time retail supply of food resources makes it difficult to coordinate the redistribution of perishable produce (and other critical food items). Consequently, food banks struggle to meet fluctuating patterns of supply and demand^{(Reference Moran, Cossar and Merkle17)}, resulting in limited provision of nutrient-dense foods (including meat, dairy, vegetables and fruits)^{(Reference Bazerghi, McKay and Dunn18)}.

The Kings Fund reported in 2022^{(Reference Holmes19)} that the 2020/2021 period saw rising rates of deprivation and obesity across England, in step with growing inequality between the least and the most deprived populations: the gap grew by 1⋅5 percentage points (from 16⋅1 % in 2019/2020 to 17⋅6 % in 2020/2021). Rising rates of obesity amongst vulnerable populations is associated with subsequent rises in future population ill health, and increased stress on health services. A healthy diet helps to protect against malnutrition in all its forms, and reduces the risks of multiple non-communicable diseases⁽²⁰⁾. People who live in more deprived areas find it harder to consume a healthy diet for a multitude of reasons, though the rising cost of healthy food is a significant factor for many. A report by the Food Foundation^{(Reference Scott, Sutherland and Taylor21)} showed that for anyone in the lowest income decile trying to follow the Eatwell Guide⁽²²⁾ would cost them almost 30 % of their disposable income. This report was published in 2018, and does not account for the contemporary cost-of-living-crisis within food and energy consumption – a crisis that compounds food insecurity risks^{(Reference Goudie23)}. Additionally, households at risk are likely to be those who self-identify as ‘too rich to be poor’ and who are experiencing in-work poverty^{(Reference Poulter, Eberhardt and Moore24)}.

A recent systematic review and meta-analysis of 36,113 adults and children showed statistically significant associations between food insecurity and obesity (OR 1⋅503, 95 % CI: 1⋅432, 1⋅577, P < 0⋅05); highlighting that food insecurity increased risk of obesity among adults and children^{(Reference Eskandari, Lake and Rose25)}. Within this same review, the narrative synthesis showed association between different types of food environments and obesity – for example between the home-food environment or food obtained from charitable sources – moreover, barriers to purchasing fruit and vegetables were identified as significant risk factors^{(Reference Eskandari, Lake and Rose25)}. Findings from qualitative studies regarding a reliance on energy-dense, nutrient-poor foods owing to their affordability and accessibility aligned with findings from quantitative studies. Results from both the qualitative and quantitative studies explored potential links between increased body weight and participation in food assistance programmes such as food banks. This comprehensive systematic review confirms that obesogenic food environments and food insecurity significantly contribute to obesity^{(Reference Eskandari, Lake and Rose25)}, adding to existing evidence that cheap energy-dense foods are favoured over healthier foods, notably fruits and vegetables. Research by Yau et al.^{(Reference Yau, White and Hammond26)} confirms that those who are food insecure have poorer diets, however, emergency food aid may not remedy this situation. An earlier international mixed-methods systematic review by Oldroyd et al.^{(Reference Oldroyd, Eskandari and Pratt27)} updated evidence on the nutritional adequacy of food parcels provided by food banks and reported that pre-prepared food parcels supplied by food banks struggle to meet the nutritional needs of their users.

Out-of-home food environment and deprivation

Access to healthy food is seen as an element to promote policy, systems and environmental change^{(Reference Lake, Townshend, Burgoine, Buttriss, Welch and Kearney28,Reference Lyn, Aytur and Davis29)} . Important within the broader concept of food access are the terms ‘affordability’ and ‘availability’. For example, in England, there is a strong correlation between a higher number of fast-food outlets in more deprived areas⁽³⁰⁾. It has also been demonstrated that deprived areas have more takeaway food outlets close to schools^{(Reference Blow, Gregg and Davies31)} as well as having an increased amount of bus shelter advertising of unhealthy food and drinks^{(Reference Finlay, Lloyd and Lake32)}.

Changing behaviours

Many of our food choices are automatic rather than reflective^{(Reference Jebb33)}. Habits and behaviours shape food choices^{(Reference Enriquez and Archila-Godinez34)}; food is intrinsically linked to cultures and social practices of domestic life^{(Reference Neuman35)}. Our food choices therefore both determine, and are determined by, our food environments, making them a critical point of intervention in food-related health and wellbeing. Preparing, sharing and eating food is both an everyday occurrence and a socio-culturally complex phenomenon^{(Reference Corvo36)} – it is determined through multi-scalar national and international policies and governance-driven decisions^{(Reference Lake, Midgley, Lake, Townshend and Alvanides37)}. Our food environment mediates our eating behaviours through the mechanisms of availability and accessibility of food. Individual behaviours are influenced by our surrounding environments. Using frameworks, such as the ecological model from Story et al., can be helpful in conceptualising this relationship^{(Reference Story, Kaphingst and Robinson-O'Brien38)}. However, measuring this association has been problematic^{(Reference Lake39)}, with studies in the area presenting conflicting results. Lake^{(Reference Lake39)} describes two studies^{(Reference Tyrrell, Greenhalgh and Hodgson40,Reference Vogel, Lewis and Ntani41)} that sought to understand the link between food environments and behaviour. Since then, a study has been published using smartphone self-reported data from 164 926 US participants (MyFitnessPal app users) and 2⋅3 billion food entries to study the independent contributions of fast-food and grocery store access, income and education to diet health outcomes^{(Reference Althoff, Nilforoshan and Hua42)}. This new work indicated there was an association between higher access to grocery stores, lower access to fast food, higher income and high educational attainment with higher consumption of fruit and vegetables, lower intakes of fast food and soda and lower risk of overweight or obesity^{(Reference Althoff, Nilforoshan and Hua42)}. Notably, there were significant variations across areas (zip codes) which had predominately black, Hispanic and white demographic sub-groups^{(Reference Althoff, Nilforoshan and Hua42)}.

Though the burden of obesity and non-communicable disease is a global problem, it is one that is transferring from high-income to low- and middle-income countries with the global distribution and marketing of ultra-processed food^{(Reference Dicken and Batterham43)}. Studies in Brazil^{(Reference Guimarães, Mais and Leite44)}, South Africa^{(Reference Reddy45)} and India^{(Reference Mehta and Bharadwaj46)} highlight the public health risks to people's food choices and health associated with advertising of ultra-processed, high in fat, sugar, or salt (HFSS) foods on free-to-air television. Moreover, in South Africa, a recent study using household survey data with publicly available geospatial (Google) data on modern food retailer locations showed that proximity to bigger-chain supermarkets and fast-food restaurants was significantly associated with overweight and obesity^{(Reference Otterbach, Oskorouchi and Rogan47)}.

Successive government strategies have sought to address obesity in the last thirty years. Between 1993 and 2020, there were fourteen obesity strategies published by the UK Government, containing fourteen strategies and 689 policies^{(Reference Theis and White48)}. However, these policies were not easily implemented in practice, and have overwhelmingly put an emphasis and reliance on individual-level behaviour change. Actions to shape public behaviour are ineffective in the absence of wider environmental–structural changes necessary to support such measures^{(Reference Swinburn, Kraak and Rutter49)}. Theis and White suggested that the emphasis and reliance on individual-level behaviours is an important factor in the UK's high rates of obesity and significant health inequalities^{(Reference Theis and White48)}.

Opportunities to improve population health

In England, the wide-reaching and ambitious National Food Strategy was bold in its vision to create a food system that was good for our health and for planetary health alongside addressing inequalities^{(Reference Dimbleby50)}. However, the lack of a committed political response to this document has proved disappointing and frustrating; this includes the potential shelving of the long-awaited health inequalities white paper^{(Reference McCay51)}. While policy continues to place the individual, rather than the environment, at the heart of government strategy, there is little scope for meaningful upstream intervention, such as the relatively successful UK Government sugar levy^{(Reference Lake, O'Malley and Moore5)}.

Food retail and the out-of-home food environment

Given the clear evidence that the food environment has an impact on population health, there are surprisingly few studies that decisively demonstrate clear evidence supporting the food retail space as a successful opportunity for influencing health. A recent systematic review^{(Reference Wilkins, Radley and Morris52)} aimed to quantify the spatial methods used to measure the ‘retail food environment’, and found great diversity in how retail food environments were measured among the 113 studies included in the analysis.

While food access and availability would intuitively appear to be important areas of opportunity, access and availability are often difficult to measure, and results remain conflicting. A recent North American example^{(Reference Sadler, Gilliland and Arku53)} found that the introduction of a food store, in what had been described as a ‘Food Desert’, had little impact on people's behaviours – highlighting that behaviour change involves more than simply increasing accessibility. However, within food supermarkets, there is evidence that purchasing behaviours can be changed by increasing the availability and promotions of healthier foods^{(Reference Piernas, Harmer and Jebb54)}.

While there is an acknowledged proliferation of fast-food outlets, particularly in more deprived areas, research has explored how to work with these food outlets (usually independent and locally owned) to improve the dietary profile of the food they serve^{(Reference Hillier-Brown, Summerbell and Moore55)}. Working with food businesses and the wider food industry, including suppliers^{(Reference Goffe, Hillier-Brown and Hildred56,Reference Hillier-Brown, Lloyd and Muhammad57)} , can help make small but important changes. In England, the effectiveness of such changes were well illustrated by the NIHR School of Public Health Research Foodscape study⁽⁵⁸⁾. A combined process of literature and scoping reviews, with co-design input from businesses and practitioners, identified successful interventions that modified meals offered by takeaways with the aim of improving diets and/or reducing obesity^{(Reference Hillier-Brown, Summerbell and Moore55,Reference Hillier-Brown, Summerbell and Moore59)} . Examples of these meaningful interventions included the introduction of five-hole rather than the regular seventeen-hole saltshaker, which reduced salt intake by over 66 %^{(Reference Goffe, Hillier-Brown and Doherty60,Reference Goffe, Wrieden and Penn61)} ; and the use of ‘light bite’ fish and chip boxes, significantly moderating portion sizes and energy intake^{(Reference Goffe, Hillier-Brown and Hildred56)}. The ready adoption of this intervention by the industry points towards long-term sustainability and potential to be used by other out-of-home food retailers. Other interventions, such as ‘master-classes’ for businesses, can improve the healthiness of the food on offer^{(Reference Hillier-Brown, Lloyd and Muhammad57)} by changing the cooking practices and menu options in takeaway food outlets among those who attend training^{(Reference Hillier-Brown, Lloyd and Muhammad57)}. Such interventions were deemed to be acceptable to business owners, required minimal effort and were cost-effective with the potential for wider use.

Other approaches that have been evaluated include the Gateshead council (a local authority in the north-east of England) multi-pronged, planning policy. Gateshead aimed to reduce childhood obesity rates locally. One aspect of this strategy was to implement three types of planning guidance (a school exclusion zone, restricting new outlets by retail density and restricting new outlets by childhood obesity rates). Brown et al.^{(Reference Brown, Xianga and Albania62)} found that this multi-pronged planning approach can significantly change the proportion and density of fast-food outlets in the short term (four years) compared with other local authorities in the north-east of England.

Though such interventions have proved effective in local and national policy, health strategy and planning must compete with economic growth priorities. In the current economic climate, these tensions may be clearer^{(Reference Lake, O'Malley and Moore5)}. For example, local authorities and planning professionals have to decide which problem is better to live with; boarded up, not-in-use, retail units or allowing those units to become fast-food outlets^{(Reference Moore, Lake and O'Malley63)}.

The changing food environment

The dynamic nature of the food environment could be seen as an opportunity for change. This dynamism was highlighted by the Covid-19 pandemic and subsequent national lockdowns. In England, the government introduced temporary measures to relax food-related planning regulations; allowing pubs and restaurants to operate as hot food takeaways to support people having to stay at home and support businesses^{(Reference Moore, Lake and O'Malley63)}. These temporary regulations permitted the change of use without the need for a planning application. In research^{(Reference Moore, Lake and O'Malley63)} with local authority professionals (in north-east England) about these temporary regulations, there were high levels of concern about the impact these measures would have on the food environment, influencing food access and population-level public health. This included worries about the implication an increase in the availability of hot food takeaways could have for dietary intake and levels of obesity^{(Reference Moore, Lake and O'Malley63)}, as observed in other studies^{(Reference Keeble, Adams and Vanderlee64)}. The growth of the ‘online food ordering and delivery platforms’ industry, which, in the UK has grown 40⋅5 % per year on average between 2017 and 2022⁽⁶⁵⁾, with further growth predicted⁽⁶⁶⁾ as the ‘at-home’ trend expands after the lockdowns cease, has fuelled these concerns.

Many of the new at-home delivery platforms are serviced by ‘dark kitchens’^{(Reference Rinaldi, D'Aguilar and Egan67)}. This is an international phenomenon and can be defined as restaurants without a shopfronts, no direct customer interaction and delivery-only commercial kitchens that rent out shared or private kitchen spaces to food businesses^{(Reference Hakim, Dela Libera and Zanetta68)}. However, there is potential for opportunities to improve choices made within these platforms using tools such as the design of a web-augmentation-based template to disrupt platform provider behaviours, empower service users and increase individual agency^{(Reference Goffe, Chivukula and Bowyer69)} or the use of a universal ‘healthiness’ rating^{(Reference Goffe, Uwamahoro and Dixon70)}. This is an emerging field and there is still much to explore.

Food advertising/marketing

The Transport for London ‘junk food advertising ban’, which placed restrictions on the advertising of foods and beverages high in fat, salt or sugar in order to help tackle childhood obesity, appeared controversial in February 2019 and garnered much negative press^{(Reference Thompson, Clary and Er71)}. However by April 2022, five local authorities (Bristol and four London boroughs (Southwark, Haringey, Greenwich and Merton)) had announced plans to take similar action^{(Reference Tatum72)}. In June 2022, Barnsley announced similar measures⁽⁷³⁾ with Brighton and Hove to make a final decision in December 2022^{(Reference Booker-Lewis74)}. The impact of the Transport for London advertising ban and the subsequent evaluation of the ban found a relative reduction in energy, sugar and fat purchased from high fat, sugar and salt products^{(Reference Yau, Berger and Law75)}; supporting policies using advertising bans as a method to reduce the purchase of these products.

Outdoor food advertising has received less attention compared with television and digital media: a recent review^{(Reference Finlay, Robinson and Jones76)} highlighted a need to understand more about its influence on consumer behaviour and health. Finlay et al.^{(Reference Finlay, Lloyd and Lake32)} note the complexities of measuring and monitoring outdoor advertising, whilst exploring the value of working with local authorities to shape the outdoor advertising environment to produce positive health outcomes for consumers.

Healthy planning

Shaping the spatial environment has been seen as a credible option to improving the health of populations. In England, The National Planning Policy Framework explicitly states the need to promote healthy communities⁽⁷⁷⁾, and that decisions involving the use of planning policies should ‘enable and support healthy lifestyles’. The Office for Health Improvement and Disparities actively encourages local authorities to use their planning system to create ‘healthy weight environments’⁽⁷⁸⁾. However, the development and use of local ‘healthy weight environment’ policies is not a mandatory requirement. Multidisciplinary working across planning and health will result in improved health and more equitable communities^{(Reference McKinnon, Pineo and Chang79)}. Planning policy and implementation is an important factor in creating sustainable and healthy communities, however, it is not a quick fix, and the wider issues around health and inequality cannot be addressed by planning alone^{(Reference McKinnon, Pineo and Chang79)}.

There is growing acknowledgement of shared responsibility between professions for broad wellbeing gains, including the promotion of a health environment^{(Reference Lake, Henderson and Townshend80)}. Research has suggested that 50 % of English local government areas have a planning policy related to the regulation of fast-food outlets^{(Reference Keeble, Burgoine and White81)}. The most common approach is the use of ‘exclusion zones’ around schools^{(Reference Keeble, Burgoine and White81)}. It is only recently that data have emerged around the effectiveness of such approaches. Brown et al.^{(Reference Brown, Kirkman and Albani82)} explored the short-term (three-year) impact of planning guidance restricting new fast-food outlets within 400 m of a secondary school and its influence on the food environment in the local authority of Newcastle Upon Tyne, UK. Using food outlet data three years pre-intervention (2012–2015), the intervention year (2016) and three-years' post-intervention (2016–2019); a difference-in-difference approach compared postcodes within the school fast-food outlet exclusion zone to those outside the fast-food exclusion zones^{(Reference Brown, Kirkman and Albani82)}. The effects of this guidance in the short term (three years) were not statistically significant when compared with a control zone. However, the authors and others in this field agree that the use of planning to improve population health is likely to be a long-term policy plan to create a sustainable healthy food environment^{(Reference McKinnon, Pineo and Chang79,Reference Brown, Kirkman and Albani82)} .

Food security

The current cost-of-living-crisis and rising rates of inflation means that even more of the global population will be pushed towards food insecurity⁽⁸³⁾. This is described by the World Bank as a ‘global crisis’ and is driving many millions to poverty, hunger and malnutrition⁽⁸³⁾, while the status quo of expansion of food banks normalises food poverty and fails to address the deeper social challenges of food insecurity. The defined long-term solution is to take action to end income and health inequalities, and to ensure populations have access to affordable and nutritious food^{(Reference D'Odorico, Carr and Davis84)}. In the short term, populations, including those living in high-income countries, need to find models of food supply to those who are food insecure. While research has highlighted the nutritional inadequacy of pre-prepared food parcels given to individuals experiencing food insecurity from foodbanks^{(Reference Oldroyd, Eskandari and Pratt27)}, there is scope to improve the quality of the food provided by these life-lines to people who are in need. Overall, there is an urgent need to plan and holistically redesign food systems to improve access to healthy affordable food.

Understanding how we can reduce food insecurity and stigma, improve access and availability to healthier foods in deprived communities is important in addressing health inequalities across all ages. One solution is the ‘social supermarket’: a social enterprise model which sells surplus food, available at discounted prices in low-income areas^{(Reference Holweg, Lienbacher and Zinn85,Reference Nott86)} ; these are usually open to the wider community (not always the case for food banks). Co-produced research is currently underway by the authors to understand more about this food insecurity intervention, examine and generate an understanding of the best ways to help social supermarket customers use healthier produce, thus having a positive impact on health and wellbeing outcomes, cost savings and food system sustainability improvements by reducing the waste of surplus food^{(Reference O'Malley87)}. Some population groups appear to be more at risk of food insecurity; this includes individuals living with a severe mental illness (SMI). There is an urgent need to understand feasible and acceptable approaches to assist people with SMI to access healthy, affordable food. This is a new field of work and collaborative research with people living with SMI is currently underway^{(Reference Giles and Smith88)}. Partnership-working with communities is core within a broad whole systems approach model^{(Reference Bagnall, Radley and Jones89)}.