A University of Sheffield study suggests that policy restricting junk food advertising on Transport for London (TfL) networks has prevented nearly 100,000 obesity cases and could save the NHS more than £200 million.
Performed in a collaboration between the University of Sheffield and the London School of Hygiene & Tropical Medicine (LSHTM), the research illuminated that the TfL advertising policy, which restricts the advertisement of food high in calories from sugar and fat or high in salt, resulted in consumers cutting down on junk food.
The study is published in the International Journal of Behavioural Nutrition and Physical Activity.
Impacts of junk food advertising restrictions
The TfL junk food advertising restrictions were first implemented in early 2019, with previous research by the team discovering that the policy led to a 1,000 calorie decrease in energy from unhealthy foods in consumers’ weekly shopping.
The new study analysed consumer purchasing habits in their weekly food shops via surveys and compared trends in London to a control group of households outside the city where junk food advertising rules were not in place.
The team estimated that the policy directly led to 94,867 fewer cases of obesity than expected – a 4.8% decrease. Additionally, limiting junk food advertising resulted in 2,857 fewer cases of diabetes and 1,915 fewer cases of cardiovascular disease. The policy is also expected to save the NHS £218m during the lifetime of the current population.
Dr Chloe Thomas, the first author of the study from the University of Sheffield’s School of Health and Related Research (ScHARR), said: “We all know how persuasive and powerful advertising can be in influencing what we buy – especially the food we eat. Our study has shown what an important tool advertising restrictions can be in order to help people lead healthier lives without costing them more money.
“We hope that demonstrating the policy’s significant benefits in preventing obesity and the diseases exacerbated by obesity will lead to it being rolled out on a national scale, something that could save lives and NHS money.”
The policy affected deprived areas more significantly
The results suggest that the junk food advertising policy had the biggest health impact on people from deprived areas in averting health conditions and reducing the level of health inequality in London. Although middle-income people cut more calories, the policy had a more significant impact on the most deprived areas, where people tend to be less healthy overall.
Professor Steve Cummins from LSHTM commented: “This work shows the potential health impacts and costs savings of the Mayor of London’s ‘Junk Food Ad Restriction’ based on our evaluation earlier this year, published in PLoS Medicine, which found that the policy reduced average household purchases of energy by 1000 calories per week.
“With more than 80 local authorities across the UK now considering the implementation of similar policies, this study provides further evidence of the effectiveness of advertising restrictions to help support decision-makers. In light of the government’s current delay in implementing obesity prevention policies outlined in the recent 2022 Health & Care Act, this is a policy that local authorities can deliver now without the need for national regulation in an effort to tackle obesity on a national scale.”
Sadiq Khan, the Mayor of London, concluded: “Junk food advertising undoubtedly plays a significant role in promoting and encouraging the consumption of less healthy foods. With child obesity putting the lives of young Londoners at risk, it simply isn’t right that children and families across the capital are regularly inundated with adverts for foods that do not support their health – that’s why I was clear that tough action was needed.
“This study, which builds on research from earlier this year, demonstrates yet again that the ground-breaking restrictions we introduced could not only influence behaviour and ultimately save lives but could directly save our NHS hundreds of millions of pounds. I am determined to continue this work to improve the health of Londoners, alleviating some of the burdens on our overstretched health service and building a better London for everyone.”