Junk food ads make children eat more

Telegraph

11-05-2025

Five minutes of junk food advertising is enough to persuade children to eat an extra 130 calories every day, British research has found.
Children and teenagers exposed to the marketing ate far more calories than other children, even if the adverts did not feature food products at all.
Those who saw or heard adverts for foods high in saturated fat, sugar and salt typically consumed around 130 more calories – equivalent to two slices of standard white bread.
The effect was the same for content featuring specific food products or with only branding, such as logos for companies such as McDonald's, KFC and Burger King.
Experts warned that the study exposed a serious loophole in the Government's planned ban on junk food TV adverts before 9pm, which comes into force in October.
Emma Boyland, the study leader, who is a professor of food marketing and child health at the University of Liverpool, said: 'This is the first study to show that brand-only food advertising affects what children eat.
'We also showed that children don't just eat more immediately following food advertising – they actually ate more at the lunch meal as well, a couple of hours after they had seen the advertising.
'This led to an overall increased consumption of 130 calories in the day just based on five minutes of advertising exposure, which of course is much less than children would typically be seeing on a normal day. That's a substantial uplift in calorie intake that, if repeated over time, would clearly lead to weight gain in young people.'
The research is the first to show that junk food adverts that simply showcase a logo rather than tempting children with images of food or drink were just as effective in persuading children to eat more.
Experts said the trend was concerning because there are currently no restrictions on such advertisements.
Prof Boyland said: 'Even short exposure to marketing of foods high in fat, salt, and sugar can drive excess calorie consumption and potentially weight gain, particularly in young people who are more susceptible to advertising and whose eating patterns influence their lifelong health.'
The findings – from a study involving 240 children aged seven to 15 at schools on Merseyside – will be presented at this year's European Congress on Obesity in Malaga.
On two different occasions, the children were shown five minutes of food-related and non-food adverts. After each exposure, they were offered snacks such as grapes or chocolate buttons, and, a while later, trays of lunch food with savoury, sweet and healthy items.
Children ate 58 calories more in snacks and 73 calories more at lunchtime after being exposed to junk food adverts.
Prof Boyland said: 'The foods that we served them weren't the same foods that were shown in the advertisements and were presented with no branding information. So it wasn't that they were driven to buy the particular food or go and consume fast food, it was just a prompt to consume what was available.'
The effect was stronger for children with a higher body mass index (BMI), with participants consuming an additional 17 calories for every unit increase in BMI. It was consistent across four different types of content: video with sound, social media posts, podcast audio-only advertising and street posters or billboards.
Prof Boyland added: 'It raises the question: are we doing enough in terms of regulation to restrict advertising in those spaces as well?'
Advertising watershed
The Government confirmed in December that a 9pm watershed would be introduced for TV adverts featuring junk food products, along with restrictions on paid online adverts. It said the move would prevent thousands of cases of childhood obesity by removing around 7.2 billion calories per year from the diets of UK children.
Prof Boyland said brand-only advertising, which seeks to create a positive impression of brands rather than push specific products, was expected to be exempt.
She added: 'This research suggests that we need to look at what's happening in the media and advertising trends, and that is certainly towards a greater emphasis on brands and creating positive associations with positive attributes like happiness, positive emotions and so on.'
'It might be that once we get this policy implemented in October, a future iteration of that policy should be considering how to incorporate brand-only advertising.'
Katharine Jenner, the director of the Obesity Health Alliance, said the study must send 'a clear message to policymakers: food advertising is driving excess calorie intake in children'.
She said: 'From October, new restrictions will limit unhealthy food adverts on TV before 9pm and online at any time – a vital step forward that will protect children from the worst offenders.
'But loopholes remain. Brands will still be able to advertise to young people even without showing specific products, on billboards and at bus stops, and children living with overweight or obesity are especially vulnerable.
'Small reductions in calorie intake can lead to meaningful improvements in children's health. If the Government is serious about ending junk food advertising to children, they must close the loopholes that will allow companies to keep bombarding them.'