A new study presented at the European Congress on Obesity (ECO) in Malaga, Spain, has uncovered alarming effects of junk food advertising on children's eating habits. Researchers found that exposure to advertisements for foods high in saturated fats, sugar, and salt (HFSS) leads children and adolescents to consume significantly more calories throughout the day, regardless of the type of media platform.
The trial, conducted by a team from the University of Liverpool, involved 240 children aged between 7 and 15 years from schools across Merseyside, UK. Participants were exposed to just five minutes of HFSS food advertisements and, in a separate session, to non-food advertisements. The study measured their subsequent intake of snacks and lunch, revealing that children consumed an average of 130 extra kilocalories after viewing junk food ads—the caloric equivalent of two slices of bread.
"Our findings offer crucial novel information on the extent, nature, and impact of unhealthy food marketing via different types of media on young people's eating behaviour," said Professor Emma Boyland, the lead author of the study. She highlighted the significance of even brief exposure to such advertising, stating, "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 study is particularly timely as many countries across Europe and around the world are considering implementing restrictions on unhealthy food advertising to combat rising childhood obesity levels. While previous research has linked product-based advertising in audiovisual media to increased immediate and later consumption among children, this study is the first to demonstrate that brand-only food advertisements—ads featuring branding elements like logos without showing the actual food products—can also increase children's food intake.
"Unhealthy food marketing leads to sustained increases in caloric intake in young people at a level sufficient to drive weight gain over time," Professor Boyland explained. "This study is the first to demonstrate that brand-only food ads, for which there is currently no restrictive advertising policy globally, increase children's food intake."
Interestingly, the type of media—whether audio-visual like television, visual like social media posts, audio like podcasts, or static images like billboards—did not moderate the effect on children's intake. Advertisement content also did not alter the outcome; brand-only ads were as effective as product-based ads in increasing calorie consumption. The researchers noted that for every standardized unit increase in body mass index (BMI) adjusted for age and sex, children consumed an additional 17 kilocalories overall.
The article was written with the assistance of a news analysis system.