Influencing what people buy and eat

Influencing what people buy and eat

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)

NIHR studies included in this section

  1. Neve KL, Isaacs A. How does the food environment influence people engaged in weight management? A systematic review and thematic synthesis of the qualitative literature. Obes Rev. 2022;23(3):e13398.
  2. Ejlerskov KT, Sharp SJ, Stead M, Adamson AJ, White M, Adams J. Supermarket policies on less-healthy food at checkouts: Natural experimental evaluation using interrupted time series analyses of purchases. PLOS Med. 2018 Dec 18;15(12):e1002712.
  3. Keeble M, Adams J, Bishop TRP, Burgoine T. Socioeconomic inequalities in food outlet access through an online food delivery service in England: A cross-sectional descriptive analysis. Appl Geogr. 2021 Aug;133:102498
  4. Huang Y, Theis DRZ, Burgoine T, Adams J. Trends in energy and nutrient content of menu items served by large UK chain restaurants from 2018 to 2020: an observational study. BMJ Open. 2021 Dec;11(12):e054804.
  5. Packer J, Russell SJ, Ridout D, Hope S, Conolly A, Jessop C, et al. Assessing the Effectiveness of Front of Pack Labels: Findings from an Online Randomised-Controlled Experiment in a Representative British Sample. Nutrients. 2021 Mar;13(3):900.
  6. Croker H, Packer J, Russell SJ, Stansfield C, Viner RM. Front of pack nutritional labelling schemes: a systematic review and meta-analysis of recent evidence relating to objectively measured consumption and purchasing. J Hum Nutr Diet. 2020;33(4):518–37.
  7. Barrett M, Crozier S, Lewis D, Godfrey K, Robinson S, Cooper C, et al. Greater access to healthy food outlets in the home and school environment is associated with better dietary quality in young children. Public Health Nutr. 2017 Dec;20(18):3316–25.
  8. Mills S, Adams J, Wrieden W, White M, Brown H. Sociodemographic characteristics and frequency of consuming home-cooked meals and meals from out-of-home sources: cross-sectional analysis of a population-based cohort study. Public Health Nutr. 2018 Aug;21(12):2255–66.
  9. Isaacs A, Neve K, Halligan J, Hawkes C. How do families living in low-income areas engage with the food environment, and what does this mean for effective obesity prevention policies? Obesity Policy Research Unit Final Report for DHSC 2020
  10. Atanasova P, Kusuma D, Pineda E, Frost G, Sassi F, Miraldo M. The impact of the consumer and neighbourhood food environment on dietary intake and obesity-related outcomes: A systematic review of causal impact studies. Soc Sci Med. 2022 Apr 1;299:114879.
  11. Alessandrini R, He FJ, Ma Y, Scrutinio V, Wald DS, MacGregor GA. Potential impact of gradual reduction of fat content in manufactured and out-of-home food on obesity in the United Kingdom: a modeling study. Am J Clin Nutr. 2021 May 8;113(5):1312–21.
  12. Hillier-Brown FC, Summerbell CD, Moore HJ, Wrieden WL, Adams J, Abraham C, et al. A description of interventions promoting healthier ready-to-eat meals (to eat in, to take away, or to be delivered) sold by specific food outlets in England: a systematic mapping and evidence synthesis. BMC Public Health. 2017 Jan 19;17(1):93.
  13. Brown H, Kirkman S, Albani V, Goffe L, Akhter N, Hollingsworth B et al. The impact of school exclusion zone planning guidance on the number and type of food outlets in an English local authority: A longitudinal analysis. Health & Place. 2021 July;70:102600.
  14. Yau A, Adams J, Boyland EJ, Burgoine T, Cornelsen L, Vocht F de, et al. Sociodemographic differences in self-reported exposure to high fat, salt and sugar food and drink advertising: a cross-sectional analysis of 2019 UK panel data. BMJ Open. 2021 Apr 1;11(4):e048139.
  15. Russell SJ, Croker H, Viner RM. The effect of screen advertising on children’s dietary intake: A systematic review and meta-analysis. Obes Rev. 2019;20(4):554–68.
  16. Coleman PC, Hanson P, van Rens T, Oyebode O. A rapid review of the evidence for children’s TV and online advertisement restrictions to fight obesity. Prev Med Rep. 2022 Apr 1;26:101717.
  17. Packer J, Russell SJ, McLaren K, Siovolgyi G, Stansfield C, Viner RM, et al. The impact on dietary outcomes of licensed and brand equity characters in marketing unhealthy foods to children: A systematic review and meta-analysis. Obes Rev. 2022 March. e13443.
  18. Packer J, Russell SJ, Siovolgyi G, McLaren K, Stansfield C, Viner RM, et al. The Impact on Dietary Outcomes of Celebrities and Influencers in Marketing Unhealthy Foods to Children: A Systematic Review and Meta-Analysis. Nutrients. 2022 Jan;14(3):434.
  19. Mytton OT, Boyland E, Adams J, Collins B, O’Connell M, Russell SJ, et al. The potential health impact of restricting less-healthy food and beverage advertising on UK television between 05.30 and 21.00 hours: A modelling study. PLoS Med. 2020 Oct;17(10):e1003212.
  20. Yau A, Berger N, Law C, Cornelsen L, Greener R, Adams J, et al. Changes in household food and drink purchases following restrictions on the advertisement of high fat, salt, and sugar products across the Transport for London network: A controlled interrupted time series analysis. PLOS Med. 2022 Feb 17;19(2):e1003915.
  21. Meiksin R, Er V, Thompson C, Adams J, Boyland E, Burgoine T, et al. Restricting the advertising of high fat, salt and sugar foods on the Transport for London estate: Process and implementation study. Soc Sci Med. 2022 Jan 1;292:114548.
  22. Hawkes C. Family Food Experience study: how can local authorities improve the efficiency and effectiveness of interventions to address inequality in childhood obesity? NIHR129771. NIHR Funding and Awards Search Website. [cited 2022 Jan 21].
  23. Parnham J, et al. An evaluation of policies to improve nutrition and health outcomes in low-income infants in the United Kingdom. NIHR School for Public Health Research. 2020 [cited 2022 Jan 21].
  24. Relton C. Fresh Street: a cluster randomised controlled trial of the benefits of a place and household-level subsidy for fresh fruit and vegetables on diet, health and the wider environment NIHR129937. NIHR Funding and Awards Search Website. [cited 2022 Jan 21].
  25. Keeble M, et al. Investigating new ways of purchasing takeaway food – NIHR School for Public Health Research NIHR SPHR. [cited 2022 Jan 21].
  26. Burgoine T. Evaluation of planning policy to regulate takeaway food outlets for improved health in England NIHR130597. NIHR Funding and Awards Search Website. [cited 2022 Jan 21].
  27. Adams J. Implementation and assessment of mandatory calorie labeling in the out-of-home sector NIHR200689. NIHR Funding and Awards Search Website. [cited 2022 Jan 21].
  28. White M, et al. Local government interactions with harmful commodity industries: an assessment of the nature, extent and need for guidance (WSB WS1 WP2). NIHR School for Public Health Research. 2019 [cited 2022 Jan 21].
  29. Knai C. Population interventions to improve diet in England: An evidence synthesis of the effectiveness of mandatory, voluntary and partnership approaches NIHR128607. NIHR Funding and Awards Search Website. [cited 2022 Jan 21].
  30. Sykes S. A realist evaluation of a public health community of practice advocacy project to restrict outdoor advertising (HFSS) – NIHR Funding and Awards. NIHR Funding and Awards Search Website. [cited 2022 Mar 10].