Two major UK supermarket chains have voluntarily stopped offering "buy one get one free" deals on foods high in fat, salt, and sugar—and researchers now have a rare chance to measure whether that actually changes what people buy and eat. Obesity and unhealthy diets are major drivers of disease in the UK, and price promotions are known to push shoppers toward less healthy options. While the UK nations are considering mandatory bans on such promotions, two chains acted early, in 2016 and 2022. This project will analyse household purchasing data, model health outcomes and healthcare costs, and interview shoppers and industry insiders to understand what happened. If the voluntary bans reduce purchases of unhealthy foods, the findings could directly inform mandatory policies across the UK and internationally. The research will also reveal whether the policies widen or narrow health inequalities between richer and poorer households, and whether supermarkets simply shift promotions to loyalty card schemes instead. The results could reshape how food is marketed and priced in every UK supermarket.
View original technical description
RESEARCH QUESTION What are the public health and related impacts of industry-led voluntary policies in two nationwide supermarket chains to ban the use of price promotions to sell HFSS foods? BACKGROUND Obesity and unhealthy diets are major causes of disease in the UK and globally. Marketing of foods high in fat salt and sugar (HFSS), including the use of price promotions (e.g. get two-for-the-price-of-one), are important contributory factors. Banning price promotions may help tackle these health issues. The four UK nations are at different stages of consideration or adoption of a mandatory ban on price promotions. However, two UK supermarket chains have already voluntarily banned their use on HFSS foods, in 2016 and 2022. This presents a valuable opportunity to understand the real-world public health and related impacts of a ban on the use of price promotions to inform adoption of mandatory bans. AIMS AND OBJECTIVES To quantify and understand changes in two supermarket chains on: a) consumer behaviour and food expenditure (overall and by sub-group) b) health, healthcare costs and socio-economic inequalities c) industry behaviour and economic performance To understand the extent to which any observed changes are due to the voluntary policy, and to disseminate the findings to inform policy and future research. METHODS The project is structured into five interlinked work packages (WPs). WP1 will engage the public and policy makers, integrate WPs and synthesize the findings and existing literature, and disseminate the findings. WP2 will provide quantitative estimates of the impact of the intervention (use of promotions; consumer purchases and food expenditure in aggregate and by sub-group) in comparison to controls using a longitudinal commercial dataset of household food purchases; findings will be triangulated with analysis in a second complementary commercial dataset (product sales dataset of loyalty card holders for one supermarket) that will also be used to explore industry adaptation and use of loyalty card price promotions. WP3 will use public health modelling to estimate the impact on health and healthcare costs (in aggregate and by deprivation quintile, age and gender) based on the observed changes in purchasing from WP2. WP4 will provide quantitative estimates of the impact on industry economic performance. WP5 will use qualitative methods to understand industry and public knowledge, attitudes and behaviours towards the use of price promotions and restrictions in their use. TIMELINES 2 years (Mar25 to Feb27) PUBLIC INVOLVEMENT Our project has been developed with the public. A member of the public who does the food shopping for her family will co-lead the public involvement and engagement work. We will recruit a diverse 10-person public panel from across the UK who will keep our work relevant; ensure our methods are appropriate for participants; and support dissemination. IMPACT & DISSEMINATION Findings can inform the adoption, implementation and/or refinement of mandatory policies in each of the four UK nations and internationally. Dissemination will focus on five groups: the public, UK national-level policymakers, UK civil society, industry, and researchers. We will disseminate our findings through academic publications, briefing notes, seminars and a podcast. A policy advisory group will facilitate a continuous dialogue with policymakers allowing timely efficient sharing of findings to inform policy.
Plain English summaries and category classifications on this site are generated by AI and may not perfectly reflect the original research.
Is something wrong? Let us know