The researchers, in partnership with the Cancer Council, Australia, studied 12,618 food advertisements from 11 countries and found that 67 per cent endorsed unhealthy food. The research builds on a previous study at Liverpool which revealed that children would consume twice as many calories from snacks after watching food adverts compared to after viewing advertising for toys and games.
The research reveals that Germany, Spain and Greece have the highest frequency of adverts promoting unhealthy foods during children's peak viewing time, compared to other European countries and parts of the US, Canada and Australia. These adverts tend to feature child-orientated persuasive techniques, such as the use of popular animated characters and celebrities.
Although the US, Canada and Australia have a lower rate of unhealthy food advertising overall, broadcasters still air the adverts more frequently during a time when children are watching.
Dr Jason Halford, Director of the Kissileff Laboratory for the Study of Human Ingestive Behaviour at the University of Liverpool said: "Obesity in young children is now a major health concern all across the world. Our studies highlight that there are global connections between advertising, food preferences and consumption. Our previous research showed that snacking on unhealthy food doubled after a child had watched a series of 'junk' food adverts. This new study demonstrates that children are specifically targeted and repeatedly overexposed to large quantities of adverts for these products.
"Young children are less aware of the persuasive intent of advertising, which makes them more susceptible to its marketing purposes. Current regulations on advertising only take into account the proportion of children watching, not the actual number. We hope this work will contribute to a review of regulations concerning the type and amount of advertisements shown during the times when children are most likely to be watching."
Emma Boyland, lead UK researcher on the project, added: "Regulations on unhealthy food advertisements were first enforced in Sweden, where companies must not generate television advertisements targeted specifically towards children under the age of 12. The UK has reformed its own regulations, but these restrictions only apply to programmes that have a certain proportion of children in the audience, rather than being based on the actual number of children watching. This means that a significant number of children could be watching among an adult audience.
"Our work suggests that further study is necessary to ensure that TV regulations are appropriate and effective at reducing children's exposure to unhealthy food advertising in the UK. An additional study would also indicate whether or not this legislation could be applied elsewhere to lessen the frequency of such advertising internationally."