Five minutes of junk food advertising results in children consuming 130 extra calories per day, researchers say.
A study found that advertising and marketing across platforms such as social media, TV and podcasts all had a similar effect.
The research, which has not yet been published in a peer-reviewed journal, was presented at the European Congress on Obesity in Malaga.
The study found that seven to 15-year-olds exposed to five minutes of adverts for foods high in saturated fat, sugar, and/or salt (HFSS) consumed on average 130 extra calories per day – the equivalent of a small chocolate bar.
Lead author, Professor Emma Boyland from the University of Liverpool, 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 research included 240 children aged seven to 15.
Analysis showed that following exposure to HFSS food ads, children consumed more snacks (an extra 58.4 calories), more lunch (an extra 72.5 calories), and more food overall (snack and lunch combined) than after exposure to non-food advertising.
Those children with a higher body mass index also showed a “greater responsivity” to the food adverts, experts found.
The Government is introducing a ban on the targeting of junk food adverts at children from October this year.
It estimates this will prevent thousands of cases of childhood obesity.
The restrictions affect advertising for less healthy food or drink on television between 5.30am and 9pm, alongside paid-for advertising online at any time.
Other types of advertising, such as billboards and other outdoor advertising, are not be affected by the change.
