News Children's Food Campaign

Junk food purchases drop thanks to London transport advertising policy

New evidence shows advertising restrictions that Sustain helped to write and implement on Transport for London (TfL) network, led to households consuming 1000 calories less a week.

Destination Junk Free London bus. Credit: Sustain

Destination Junk Free London bus. Credit: Sustain

Research led by the London School of Hygiene and Tropical Medicine has shown that restricting unhealthy food adverts across TfL has significantly reduced unhealthy food purchases. According to the findings, the Mayor of London's Healthier Food Advertising Policy has led to households buying 1000 fewer calories (6.7% less than would have happened without the policy) per week from high fat, salt and/or sugar foods and drinks (HFSS). That's equivalent to one big bar of chocolate less each week.

The restrictions, which Sustain helped to write and implement across the TfL network, had a particularly strong impact on sugary purchases: confectionery and chocolate had the sharpest reductions of all HFSS products with a decrease of 20% (318 calories) per week. This is notable when compared with other interventions. The study found that TfL's advertising restrictions had an even more significant impact on sugar purchases than the Government's successful Sugary Drinks Industry Levy (SDIL), an up to 82g reduction compared to SDIL's 32g.

The Mayor of London introduced the Healthier Food Advertising Policy across the TfL network in 2019 to address health inequalities and improve children's health. This followed public consultations which showed that 82% of Londoners were supportive of the proposals. The policy swaps out advertising of unhealthy food and drinks, replacing them with healthier products. Companies have continued to advertise food and drink on the TfL estate by adapting their advertising to comply with the policy. TfL's advertising revenues were sustained over the first year of the policy being live, with TfL reporting an increase of £2.3m (before Covid). In its second year, advertising revenues continued to be unaffected by the advertising policy, however, there were general losses due to Covid restrictions reducing customer numbers.

Sustain advised the Mayor of London’s team on the writing and implementation of the Healthier Food Advertising Policy and has subsequently supported five local authorities to bring in their own policies: Bristol, Greenwich, Haringey, Merton and Southwark. More than 70 local authorities have contacted Sustain for support with their own Healthier Food Advertising Policies and Sustain continues to collaborate with them to progress policy implementation.

The findings come at a time when there are concerns that the Government is considering delaying or diluting national TV and online advertising and in-store promotions regulations aimed at reducing public exposure to marketing of HFSS foods and drinks. This week, senior health leaders have warned Prime Minister Boris Johnson, who has himself attributed poor health and weight management with higher risk of serious complication, not to deviate from his own obesity strategy, despite intense pressure from industry and some members of his own party to u-turn on measures to protect children’s health.

Kath Dalmeny, Chief Executive of Sustain, said:

What a momentous win for children’s health! The news that the Mayor of London’s Healthier Food Advertising policy works will be game-changing in London and across the UK. This research proves that when the spotlight is taken off junk food, we buy less of it. This can help us make more room in our minds and shopping baskets for healthier foods and drinks. It is also good news that the policy does not affect advertising revenues, supporting the case for regional and national governments to implement these restrictions. We look forward to working with them to do so.

Barbara Crowther, Sustain's Children's Food Campaign Coordinator, said:

We’re delighted to see that Transport for London’s healthier food advertising policy is working as intended and is helping to stem the tide of junk food advertising that constantly nudges us towards less healthy options. It acts as an incentive to business to produce and put healthier options into the spotlight instead, and to play their part in making London a healthier city for us all, and especially children. The research offers further valuable insight and evidence that we hope will also give confidence to other regional and national policy makers: healthy food advertising regulations do work and have a role to play in supporting healthier food choices.

Sadiq Khan, The Mayor of London, said:

It is a scandal that London has such high levels of child obesity and, that in a city as prosperous as ours, where you live and the amount you earn can have such a huge bearing on whether you have access to healthy and nutritious food.

There is no denying that advertising plays a massive role in the choices we make, and I am pleased to see the positive impact these groundbreaking measures have had, leading to a real reduction in the amount of junk food being purchased.

I am determined to continue this work, starting with providing local councils with a Toolkit to help effect change at a local level, so Londoners’ lives can be improved and the burdens on our overstretched heath service reduced.

The data, published in PLOS Medicine, comes from the evaluation of the TfL policy which was independently funded by the National Institute for Health Research, and carried out by the London School of Hygiene and Tropical Medicine. The researchers used data on nearly two million grocery purchases of HFSS foods and drinks collected by Kantar, a commercial consumer data company. The study ran from 18 June 2018 to 29 December 2019 and looked at average weekly purchases of HFSS products in 977 London households. The team compared these with purchasing data from a control city in the North of England to estimate what would have happened without the policy. After controlling for key factors including sex, age, socioeconomics, number of adults and children in the household and festivals such as Christmas, they estimated the changes in household purchases of energy and nutrients from HFSS products associated with the TfL advertising policy.

Sustain's Healthier Food Advertising Policy toolkit, commissioned by the Mayor of London, includes case studies, policy recommendations and step by step actions and is now available to support local governments interested in pursuing their own local policies.

Published Thursday 17 February 2022

Children's Food Campaign: Better food and food teaching for children in schools, and protection of children from junk food marketing are the aims of Sustain's high-profile Children's Food Campaign. We also want clear food labelling that can be understood by everyone, including children.

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