Food and drink high in fat, sugar and salt - out of home advertising restrictions: rapid evidence review

Findings

The findings of the current research are summarised by the following themes:

• Who has implemented or plans to?
• The scope of product restrictions
• The scope of advertising site restrictions
• Challenges to policy implementation
• Facilitators of policy implementation
• Effectiveness of policy implementation
• Involvement of young people
• What can be learnt from local authorities?
• What can be learnt from industry and advocacy groups?

Who has implemented or plans to

There is some degree of uncertainty as to how many and which local authorities have implemented or plan to implement a policy. For the current research, information was obtained from published policy documents, and interactions with Outsmart and Sustain (Annex 3). Outsmart^[39] are an organisation who represent outdoor media companies such as JCDecaux and Clear Channel. Sustain^[40] are a third sector organisation who advocate for food and agriculture policies. The Commercial Determinants Coordinator at Sustain advised the Mayor of London and his team on writing and implementing the Greater London Authority (GLA) policy. Sustain have since published a toolkit ^[41], outlining in detail the process of implementing policies that restrict the advertising of unhealthy food and drinks that has been followed by other local authorities as well as the Mayor of London.

Based on published policy documents the current research was able to confirm 14 local authorities with a signed off policy^[42]. The Transport for London (TfL) Network was the first to restrict advertising of HFSS products across the London underground, rail network, buses, taxis, and TfL operated outdoor spaces ^{[43] [44]}. Local authorities that have since signed off a similar policy include Barnsley, Bristol, Haringey, Knowsley, Luton, Merton, Sefton, Southwark, Tower Hamlets, York, Peterborough, and Brighton and Hove.

However, it seems that engagement with the policy is more widespread than can be ascertained through available policy documents. Indeed, a spokesperson from Sustain confirmed that the policy has now been successfully implemented in 20 English local authorities, over and above the TfL network, with 150 further local authorities in England in the consulting stage^[45]. At the time of this research, no Scottish local authorities have engaged with Sustain. With several policies announced in 2024^{[46] [47]}, it is possible that more local authorities will release public policy documents in the coming months as momentum to restrict unhealthy advertising builds across England, a pattern not yet evident in Scotland.

Scope of restrictions on outdoor advertising of HFSS foods

Product restriction

The current research revealed that all local authorities utilise The Nutrient Profiling Model 2004/2005 (NPM) in their policy^[48]. The NPM was originally developed by University of Oxford researchers for the Food Standards Agency (FSA) to help media and communications regulator Ofcom reduce the exposure to HFSS advertising on children’s TV. The NPM enables HFSS products to be differentiated from non-HFSS products using a points-based scoring system^[49] .

Across all local authorities with a confirmed advertising policy, brand-only advertising is also restricted as many brands are associated with unhealthy products. This means that brands can advertise only if they promote a non-HFSS product as the basis of their advertisement. Incidental advertising is also restricted across all confirmed local authorities which means that HFSS products cannot feature in an advertisement even if it is not the focus of the advert (Annex 3). For example, in the TfL estate, advertisements for comedian Ed Gamble’s tour were requested to be altered to replace the image of a hotdog with a healthier alternative^[50].

The TfL network included an exceptions process in their policy. This allowed advertising companies to request an exception for a particular product if they could demonstrate and evidence that it did not contribute to childhood obesity. However, most local authorities did not include an exceptions process in their policies on the recommendation of Sustain, in part due to administrative burden. A Haringey spokesperson confirmed that as a small local authority, they would be unable to monitor an exceptions process. Furthermore, in a published article, stakeholders expressed difficulty with evidencing whether a product contributed to childhood obesity, with the data being expensive to purchase and providing little clarity on the extent of children’s consumption ^[51].

While the ASA have regulations around restricting advertising of harmful products, some local authorities have included products such as baby formula, gambling, and alcohol in their policies. York, for example, prohibits advertising tobacco, vapes, alcohol, gambling, cosmetic surgery, and weapons as well as HFSS products. Haringey policy covers alcohol, gambling, baby foods, loans, pawn shops, weapons, violence or anti-social behaviour, pornography and sexually explicit services and products, cosmetic surgery, tobacco and related products and unproven health and weight loss products. Other local authorities have focused only on HFSS food and non-alcoholic drinks.

Site restrictions

The extent of the site restrictions differed by region, as advertising estates typically contain both council-owned and privately owned advertising sites. Implemented policies typically apply only to council-owned advertising sites, which may be a small proportion of the total advertising in an area. Privately owned advertising sites that are not council-owned cannot be controlled by the policy. This is a challenge that was highlighted during conversations with local authority representatives and noted in policy documents (e.g. Brighton & Hove, Bristol, Haringey and York; see Annex 3) as it leaves little scope for local authorities to influence advertising on these sites.

Of the council-owned sites, some may be managed by the local authority, while others may be managed by a media company such as JCDecaux, Clear Channel, Ocean, or One Digital. For example, in Brighton and Hove, Clear Channel clean and manage council-owned bus shelters and pay an annual fee to advertise^[52]. If agreed, advertising restrictions for HFSS products can be written into a current advertising contract when it is due for renewal. In York, JCDecaux holds the largest contract on bus shelters, owning 142 sites. A new 15-year contract has been negotiated with HFSS advertising restrictions included in the policy. If the contract was not renewed, there was a risk that all bus shelters would be dismantled by JCDecaux, with the council having to source, install and maintain new bus shelters^[53].

Additionally, if HFSS advertising restrictions are written into new contracts, they may not come into effect at the same time, potentially limiting the impact of the policy in an area. Scottish Government-funded research by Obesity Action Scotland and East of Scotland Partnership attempted to map the outdoor advertising landscape in four local authorities in Scotland ^[54]. It was found that JCDecaux, the main advertising partner in Edinburgh, control six large hoardings all owned by the council, with the length of the contract spanning 10 years. In Fife council and West Lothian, the main advertising partner is Clear Channel, with contracts renewing after seven years in Fife and 15 years in West Lothian. However, some contracts may come with negotiating windows. In York, for instance, the contract was due for renewal in 2023 but was extended by 12 months to allow for negotiations^[55].

Policy implementation

Policy implementation has been independently evaluated and published relating to the TfL and Bristol advertising restrictions^{[56] [57]}. In these studies, qualitative interviews were conducted to understand stakeholder perspectives on the process and implementation of the new policy. Together, both articles provide insights into challenges that occurred when implementing the policies.

Challenges

• Operationalising the concept of junk food
• Greater impact on some businesses than others
• Tension between the policy goals and supporting the economy
• Business opposition

In relation to the TfL policy, stakeholders reported that operationalising the concept of ‘junk food’ was challenging, despite using the Nutrient Profiling model (NPM). The NPM produces a score per 100g of food/drink, meaning products that are generally consumed in small quantities, such as olive oil and butter, could not be advertised. In addition, some products that would usually be associated with “junk food” were policy compliant according to the NPM. For example, advertisements of fried chicken continued to be placed on the TfL network due to the protein content. Sustain remarked that it is not mandatory for out of home companies to disclose their nutritional information per 100g, which has led to some brands only disclosing nutritional information per serving size. Therefore, brands are able to claim that their products are compliant with the policy. One recommendation in the published literature is that the NPM be supported by additional tools to help achieve policy goals. Local authorities can do this by emphasising the importance of advertising healthy portion sizes. For instance, brands may be encouraged to advertise a slice of pizza rather than a whole pizza. Alternatively, the more recent version of the NPM 2018, which reflects current UK dietary recommendations could be used instead^[58].

An additional challenge reported by stakeholders was that some food companies were more negatively impacted than others due to having a narrower portfolio range. If a brand did not have an HFSS compliant product available, for example, a confectionary brand, then they were unable to advertise on the TfL estate. Engaging with industry early on, prior to implementation, is recommended to enable time for any necessary changes to advertisements ^[59].

In Bristol, challenges included conflict arising between the goals of the policy and the objective of stimulating the economy through events and festivals. With no dedicated project lead appointed to control and monitor the policy after implementation, stakeholders were left not knowing how to adhere to the advertising policy while also promoting nightlife to stimulate the economy through culture and leisure events. Additionally, there were concerns about the impact the policy could make overall as the council only owns a relatively small proportion of advertising sites and has little control over what can be advertised on private sites.^[60]

Two published studies analysed media representations and corporate political activity to understand opposition in relation to the TfL restrictions ^{[61] [62]}. Industry responses to the draft London Food Strategy consultation showed that most of the food and advertising industry respondents opposed the policy. These respondents included The Advertising Association, British Soft Drinks Association (BSDA), UberEats and media companies including Clear Channel, JCDecaux and Outsmart. Media opposition to the HFSS restrictions or “junk food ban” was analysed, and the typical arguments made against the policy were identified. The main arguments were that it was not appropriate for the Mayor of London or TfL to tackle childhood obesity, nor was restricting advertising an effective method of doing so. These arguments were justified by identifying alternative issues that should be prioritised such as knife crime, smoking or body image. The media also used a phenomenon called the Nirvana Fallacy^[63], by claiming that public health interventions are typically only effective to the small number of people exposed to them, implying that a guaranteed solution to obesity is possible. Second, the media compared the policy to alternative, unspecified ideals, such as suggesting there are better solutions, but without providing any suggestions. According to one GLA representative, the policy was never intended to be a ‘silver bullet’ but rather one contributor of improved health outcomes and, potentially, a reduction in childhood obesity in the longer term.

Facilitators

Several factors facilitated policy implementation in Bristol and GLA:

• Support
• Build up to policy implementation
• TfL setting a precedent
• Culture of the area

For both the TfL restrictions and in Bristol, there was a significant amount of public support, which facilitated implementation of the policies. The consultation in response to the draft London Food Strategy contained support predominantly from charities and smaller businesses including Diabetes UK and the Food Ethics Council. Others, such as Food Exchange Ltd (an independent fruit and vegetable wholesaler), agreed upon the concept but had reservations due to the potential financial impacts including the potential loss in revenue from the reduction in advertising^[64] (see also Annex 2).

Media representations in favour of the ban centred around the need to address health and social inequalities, emphasising the public health crisis around childhood obesity and the subsequent economic burden on health services. Local, as opposed to national, publications were more likely to represent the policy in a positive light, depicting the mayor as a ‘trailblazer’ of a public health trend. This supported the idea that other local authorities should have autonomy to implement similar restrictions^[65].

Local authority representatives interviewed for the current research reported that local businesses and the local community were generally supportive of the measures. However, some stated that it was not considered necessary to run a public consultation with local people prior to establishing the policy considering the small size of their advertising estate.

Another facilitator was the build up to policy implementation. Although an extensive advertising policy was not already in place in Bristol, the council had made a prior commitment to embedding health into all policies, supported by the mayor. This meant that there was already a positive climate around implementing policies that improve health outcomes. There was also a significant amount of time spent in the planning stages and in drafting the policy, which took 12 months. A further six months were then focused on engaging wider stakeholders to help with decision-making. This enabled the policy to pass council approvals. The prior implementation of the TfL policy and Sustain’s support set the precedent for Bristol to follow their policy template. It is acknowledged in the paper that ‘groundwork’ carried out by the TfL team enabled the policy to be drafted with relative ease^[66]. Policy implementation in other areas is a recurrent theme throughout the policy documents included in this research as local authorities used Sustain’s guidance and looked to other similar areas to base their policy on. For example, decision-making in Sefton was informed by Barnsley’s advertising policy (Annex 2).

The culture of the local authority was also a facilitator as Bristol is generally a progressive city and because of this, there was widespread acceptance from the local community. Indeed, AdBlock Bristol, a group who campaign for cities free of outdoor advertising, published an article describing the negative effects of outdoor advertising on health and wellbeing, stating that the new advertising policy was a step in the right direction, but further action on restricting the build of new billboards and digital screens was needed^[67]. Taken together, this suggests that local authorities planning to implement a similar policy may benefit from the momentum built from by policies being implemented in other areas.

Impact of advertising restrictions

Across all interviews with local authority representatives, evaluating the impact, success or effectiveness of the advertising policy was an area of challenge. In their policies, local authorities cited published findings from the independent research carried out on the effectiveness of the TfL restrictions to support implementation of the policy in their own area.

The following section provides a detailed review of the evidence evaluating the effectiveness of implemented advertising restrictions. Three articles are reviewed in the following section and each report on the following:

• The reduction in calories/energy purchased from HFSS products during TfL restrictions (London School of Hygiene and Tropical Medicine study)
• The impact of TfL restrictions on obesity and NHS costs (Sheffield University)
• The reduction in self-reported advertising exposure (Bristol University)

The reduction in calories/energy purchased from HFSS products during TfL restrictions

One of the research studies, published in 2022, was carried out by the London School of Hygiene and Tropical Medicine (LSHTM)^[68]. The authors investigated the impact of restricting advertising of HFSS food and drink on the TfL estate using purchase data from Kantar Fast Moving Consumer Goods (FMCG) Panel. Average weekly household purchases of HFSS products were recorded from a random sample of households in Greater London before and after the TfL restrictions were implemented. The researchers used a controlled interrupted time series analysis to estimate change in purchases of HFSS products compared to a counterfactual scenario, an estimate of what would have happened had the advertising restrictions not been implemented. The counterfactual scenario was created by combining pre-implementation data in London and post-implementation data in a control area, the North of England (NE). The North of England was chosen as a control area firstly because it is subject to the same seasonal fluctuations and underlying trends in HFSS purchasing as London. Second, it enabled the researchers to minimise spillover effects; that is, the likelihood of the control group being contaminated by individuals who regularly commute to London.

The research showed that, overall, weekly energy purchased from HFSS products was 6.7% lower in London compared to the counterfactual scenario. This equates to 1,001 kcal per household, per week and 385 kcal per person per week for the average household size of 2.6 people. Chocolate and confectionary saw a reduction of 317.9 kcals and biscuits 198.3 kcal. However, sugary drinks, cereals and savoury snacks increased by 19.6 kcal, 4.1 kcal and 61.1 kcals respectively.

The main findings were corroborated by the follow-up sensitivity analysis, which showed no difference in energy purchasing when the timeline was changed to an earlier date, before the restrictions had come into effect. This shows that the changes observed were localised to the time of the TfL restrictions, therefore suggesting that the policy was the cause of change. Further sensitivity analyses showed that purchasing of non-HFSS products did not rise, suggesting that energy purchased was not displaced to other products. In addition, the effect was greater in people who used public transport regularly, although this difference did not reach statistical significance.

Taken together, the main findings and sensitivity analyses reveal that restricting advertising of HFSS products on the TfL estate resulted in less energy purchased from HFSS products. However, it is important to note the findings reflect a slowed rate of growth rather than an absolute reduction in purchasing of HFSS products. Purchasing of HFSS products still increased, but at a slower rate than if the restrictions had not been implemented.

The study was also limited to evaluating the impact of take-home grocery shopping, with out-of-home purchases excluded due to lack of available nutrient data. Therefore, it was not possible to conclude whether the policy resulted in reduced takeaway purchases. A further limitation acknowledged by the authors is the possibility that some advertisements were displaced from Greater London to the control area, resulting in confounding in the control group.

The impact of TfL restrictions on obesity and NHS costs

In a further study by the University of Sheffield, the researchers used the data and findings from the LSHTM study and modelled the predicted effect of the intervention 12 months later^[69]. The School for Public Health Research diabetes prevention model enables medium to long-term economic predictions of health policies using annual cycles. The model predicted that 12 months after implementation of the TfL restrictions, there would be 4.8% fewer people with obesity and 1.8% fewer people overweight compared to a no-intervention control group. It was also predicted that the reduction in obesity and related diseases would save £218 million in health care costs over the lifetime of the current population in Greater London. This study takes the LSHTM study a step further in modelling the potential impacts on reducing obesity and the associated costs to health care. However, similar policies in other areas with lower population density and less well-established travel networks may not be as effective. Therefore, evaluative research is required in areas beyond the TfL network.

Reduction in self-reported advertising exposure

There is a significant gap in the literature assessing the impact of the policy in local authorities outside of London. The University of Bristol have recently published an article measuring advertising exposure of HFSS products using self-reports by administering a survey to respondents in Bristol^[70]. In this study, a correlation was found between self-reported advertising exposure and measured advertising, suggesting that self-reporting may be a viable method to gain baseline data on advertising exposure. Although the follow-up data have not yet been published, measuring a reduction in advertising exposure is potentially a more realistic avenue for other local authorities to pursue rather than health outcomes, which are multifactorial and slow to change⁴¹ . However, obtaining baseline data on advertising exposure would require considerable time and resources, which may not always be possible.

Involvement of young people

In implementing the policy, local authorities have worked with young people in a variety of ways. One method has been to engage with Biteback 2030, a youth activist movement focused on challenging the food industry. A video about their recent campaign, the Gut Punch, demonstrates how companies target children and young people with unhealthy advertising^[71]. In their manifesto, they urge the UK Government to fully implement legislation to restrict the advertising of HFSS products. Showing young people this video could be a first step in involving them in the process of policy implementation.

In other areas of the UK, young people have been at the forefront of making change with regards to unhealthy food/drink advertising. Peterborough Youth Council launched their Community Food Champions campaign inspired by Biteback 2030, submitting a petition to restrict advertising of HFSS products on council-owned land. The policy was subsequently implemented in Peterborough following the Youth Council’s campaign. Finally, Lewisham Council gained funding to conduct The Lewisham Childhood Obesity Trailblazer Programme (COTP), which was implemented in 2019 to 2020 to monitor the progression of action to outcomes with regards to reducing obesity ^[72]. The young people’s council were included in the partnership steering group, as well as public health experts, industry partners and local authority networks, providing an example of how different sectors can work together to achieve a common goal of tackling obesity. The materials for this campaign were also developed with young people, again demonstrating that the voice of young people is valued.

What can be learnt from local authorities in England?

The following section focuses exclusively on themes that emerged from the five interviews with local authority representatives.

Key themes were:

• Clear policy objective
• Constructive engagement with businesses
• Tailoring to individual local authority contexts

First, it was of paramount importance to identify and commit to a key policy objective. For example, the Mayor of London’s core principle was to tackle childhood obesity^[73]. In other local authorities, the policy objective centred around reducing health inequalities or offering choice. Unwavering commitment to a core principle is the key to guiding decision-making, responding to opposition, and reducing trivial arguments around compliant products.

Second, local authority representatives described the ways in which they maintained good relationships with businesses and advertising companies. It was made clear to advertisers that they were not being banned from advertising their brands, but that they could still advertise if the advertisement contained a healthier, HFSS compliant product. In some cases, the local authority worked with brands to find alternative ways to advertise their product.

Third, the policy was tailored to each individual local authority. It was acknowledged that due to having a small number of council-owned advertising sites relative to the overall number of advertising sites in the local authority, the impact of the policy may be more limited in some areas than in the TfL estate. However, local authority representatives emphasised the value of the policy in reducing health inequalities, such as reducing the prevalence of HFSS advertising in areas of deprivation. Finally, local authorities were proud to be amongst the first to implement the policy in the UK.

What can be learnt about industry and advocacy groups?

From one industry conversation

Outsmart explained that the proportion of advertising revenue that goes to OOH advertising is approximately 3.3% of all advertising revenue, whereas online advertising accounts for 75% of revenue and TV for 13%. Some local authorities have contracts with a media partner to manage their advertising estates, however this tends to be larger local authorities with large advertising estates. Smaller local authorities may manage the advertising themselves (Annex 3). Outsmart described how it may be challenging to understand contracts between local authorities and media owners, who are reluctant to share details about contracts due to competing with other media owners for tenders.

From one advocacy group conversation

Sustain commented that despite the evidence, it remains a significant challenge to get policies ‘across the line’ due to industry tactics and fear of revenue loss. They recommend to delay announcing the policy during the planning phase and to be prepared for opposition. One alternative suggestion to a national approach in Scotland is to inform all local authorities about the policy and gauge interest from there. As in England, local authorities may experience a sense of pride about being amongst the first in Scotland to implement the policy.