Responding to new research on the effectiveness of the TfL HFSS advertising restrictions, the Advertising Association has issued the following statement.
Sue Eustace, Director of Public Affairs, Advertising Association, said:
“Tackling obesity is an important issue. Two research studies published by LSHTM in February and by the University of Sheffield last week seem to show that the restrictions the Mayor introduced in 2019 on HFSS advertising on the TfL estate were successful in this respect, but the policy has clearly failed.
Childhood obesity continues to increase significantly in London, with 30% of Year 6 children now classified as obese. This is higher than in the rest of England, including the North East – used as the first study’s control group – and considerably higher than in 2019 when the restrictions were introduced.
We are sceptical about the claimed success of the TfL HFSS ad restrictions, given that the Government’s estimate of an HFSS online ban and TV advertising watershed restriction is that it would only reduce calorie intake by 2-3 calories a day. There are some clear and obvious discrepancies and we believe that these TfL study results should not be relied upon in support of policies that restrict HFSS adverts.
There are some serious methodological gaps in the models used in the two research studies, the first of which concluded that London households are purchasing 1000 fewer calories per week and the second that there are 95,000 fewer cases of obesity in the capital.
An analysis by SLG Economics points out some of the flaws:
- The first study misses out over half (by calories purchased) of the HFSS product groups and as a result does not explain where 57% of the reported reduction in calories comes from.
- It also excludes out-of-home purchases and deliveries where one might expect TfL ads to have a much greater impact, again questioning the credibility of the results.
- The study suggests results that are 32 to 109 times higher than the expected results from a 9pm watershed ban on HFSS adverts on TV – this is not a credible result.
- HFSS advertising continues to be widely available and widely read in free newspapers on the underground, further questioning the study results.
- It is a serious methodological gap to not take into account the extent to which people in the survey would have had the opportunity to see HFSS adverts on the TfL estate and how that would have changed over the period of the study.
- The results fail an important statistical test which reduces the statistical validity of the results and the robustness of the conclusions.
From these conclusions, we would question if there is any evidence that concretely points towards ad bans reducing levels of obesity. While we all agree that addressing obesity requires a holistic, evidence-based approach, the rules governing HFSS advertising are already among the strictest in the world. Advertising plays a vital role in funding sporting activities and can be part of the solution to tackle the obesity epidemic. Coupled with community-based levelling-up initiatives, policymakers should be supporting schemes that are proven to cut childhood obesity and have a real impact on promoting active lifestyles.”
This webpage has been updated as of August 9.


