Closing the doors on junk food advertising – promising evidence from TfL

The TfL advertising restrictions are a story of success. A recent study has found that London households consumed 1,000 fewer calories from HFSS products as a result of Transport for London’s (TfL) advertising restrictions.  The paper, produced by the London School of Hygiene and Tropical Medicine, evaluated the impact of advertising restrictions upon foods high in fat, sugar and salt (HFSS).

The Mayor of London’s ban on junk food advertising was implemented across the TfL network in February 2019 to help tackle the impact of HFSS foods on overweight and obesity in the city. The restrictions included all adverts for HFSS food and non-alcoholic drinks considered by Public Health England to be “less healthy” such as cheeseburgers, chocolate bars, sugary drinks and salted nuts. Food establishments such as takeaways or restaurants, or food and drink brands, are now only able to promote healthier food items within the TfL network. Despite this significant change within London’s transport network, TfL witnessed an increase in advertising revenue of £2.3 million during the first year of the restrictions being in place.

This latest study conducted a range of tests on a large sample of food and drink purchases from households in London and compared results to a predicted trend using household samples in the North of England that had similar purchasing habits but were not exposed to any advertisement restrictions. Purchases of all products categorised as HFSS were examined in addition to separate analysis of five HFSS categories (chocolate and confectionary, puddings and biscuits, sugary drinks, sugary cereals and savoury snacks). The results revealed an association between the policy being implemented and households in London purchasing fewer unhealthy foods:

• Weekly household energy purchases from HFSS products decreased by an average of 6.7%, or 1,001 calories, after the introduction of the advertising restrictions.
• Weekly calories consumed from chocolate and confectionary decreased by 19.4% (317.9 calories).
• Individual energy purchases decreased by 385 calories per week - equivalent to 1 and a half bars of chocolate.
• Average weekly purchases of fat, saturated fat, and sugar from HFSS products also decreased by 6.5% (57.9g), 7.3% (26.4g), and 10.5% (80.7g), respectively.

The outcomes of this study are hugely promising as London currently has some of the highest obesity rates in Europe, while obesity in children has risen sharply in recent years. Furthermore, children from lower socioeconomic households and boroughs are disproportionately affected and are twice as likely to be living with obesity than their less deprived peers. Policies such as the TfL advertising ban take aim at structural-level causes of overweight and obesity and are therefore more likely to have an equitable impact on everyone, no matter their socioeconomic position. Encouragingly, 70 other local authorities from across England are now planning to echo the work undertaken within London and restrict outdoor advertisements on HFSS foods.

In November 2021, we published a report which aimed to understand the influence local authorities have on outdoor advertising in the East Region of Scotland. The report explored the benefits, opportunities, risks and challenges associated with potentially introducing local health-protecting advertising policies. A key finding of our report was the desire for national level regulations which would offer a level-playing field for local authority advertising. Following the evidence presented in the TfL study, it is fair to say that a similar policy applied across the whole of Scotland would only benefit people’s health.

Read the full paper on the TfL restrictions here