Mayor uses junk science for junk food Ad Ban

Misleading research wildly exaggerates impact of TfL's Ad Ban

• This morning’s misleading research has already been debunked, as childhood obesity in London continues to rise (per NHS data).

• NHS Data shows rising obesity with London seeing the highest increase of any Region.

• Christopher Snowden tweets that it is “the worst piece of activist-driven quackery in a journal this year.”

• Emma Best AM says it is “brazen for the Mayor to claim success on the basis of junk science which has been roundly and repeatedly debunked.”

The Mayor of London is relying on ‘junk science’ to justify his failed Transport for London junk food ad ban, according to Emma Best AM, GLA Conservatives Health spokesperson.

This morning, new research was published purportedly showing nearly 95,000 people in London were prevented from becoming obese because of the TfL policy.

The Mayor of London claimed this study ‘demonstrates yet again’ the effectiveness of his junk food advertising ban on the TfL network, introduced in February 2019.

However, this afternoon the research has been immediately and roundly debunked, on the basis of a flawed methodology which uses misleading modelling.

Christopher Snowden, head of lifestyle economics at the Institute for Economic Affairs, tweeted his analysis of the research, which he describes as “the worst piece of activist-driven quackery in a journal this year.”

“The model is based on a factoid from another modelling study which I wrote about in February. That was also one of the worst pieces of garbage I've ever seen. The authors claimed that London households ate 1,000 fewer calories of HFSS [foods high in fat, sugar or salt] after the ban. This wasn't true in any sense. They could only pretend it was true by creating a ridiculous counterfactual in which consumption rose sharply for no reason if there hadn't been a ban.”

The research is the second of its kind to be peddled by the Mayor to justify the ban and subsequently be debunked.

Earlier this year, the GLA Conservatives Food For Thought: The TfL Junk Food Ad Ban and the Mayor’s Failure to tackle child obesity in London report set out the Mayor’s failings on this issue, and his reliance on flawed and misleading research.

It also found that, as of March 2022, the ban’s poor and inconsistent enforcement has meant McDonald’s ads continued to be permitted on the TfL network, almost three years after the policy was first introduced.

Emma Best, GLA Conservatives Health spokesperson, said:

“With rising childhood obesity in London, amongst reception and year 6 children, it is brazen for the Mayor to claim success on the basis of junk science which has been roundly and repeatedly debunked.”

“With up to £25 million in lost revenue and a flawed and inconsistent roll-out of this policy, Londoners rightly expect the Mayor to stop pushing dodgy research to cover up his mistakes, and start taking serious action to improve the health of London’s children.”

Notes for editors:

• The research released this morning is from the University of Sheffield and the London School of Hygiene and Tropical Medicine. The study is published in the journal International Journal of Behavioural Nutrition and Physical Activity, available at this link.

• The Mayor commented on the University of Sheffield press release, available here.

• As set out above, the methodology used in the research is flawed and cannot be used to claim success for the TfL junk food ad ban. Far more reliable NHS data shows that child obesity has increased in London.

• The Mayor introduced the Junk Food Advertising ban on 25th February 2019. The policy is based on the High Fat, Salt and Sugar (HFSS) foods.

• The purpose of the ban was to “tackle childhood obesity” which can be the only real measure of success.

• When the policy was introduced it was estimated that it would cost £25 million in lost revenue.

• The policy sparked controversy when it was introduced as it removed adverts for the likes of Strawberries and Cream at Wimbledon and McMillan Coffee Mornings. It also led to removing adverts for Farmdrop just because their adverts showed butter and bacon.