Unhealthy food advertising on social media: policy lessons from the Australian Ad Observatory.

The World Health Organization and public health experts are calling for urgent restrictions on the online marketing of unhealthy food. The harmful effects of exposure to advertising for 'unhealthy foods', including discretionary foods high in fat, salt or sugar, particularly for children, has prompted a proposed policy action in Australia to prohibit all online unhealthy food marketing. We used a novel data donation infrastructure, the Australian Ad Observatory, to create a dataset of 1703 ads promoting top-selling unhealthy food brands that had been placed by 141 different advertisers on 367 individual Australians' Facebook feeds. We used this dataset to identify any targeting of unhealthy food ads towards young people (18-24), investigate harmful marketing practices by four of the top advertisers (KFC, McDonald's, Cadbury and 7-Eleven); and demonstrate how online advertising may be made observable and accountable. We find indications that young people (18-24), especially young men, are being targeted by unhealthy food, especially fast food, ads. We also find that unhealthy food brands use potentially harmful marketing strategies to appeal to children, young people, parents and the broader community, including cartoon characters, and associations with popular sports and greenwashing. The policy implications of our findings are that a broad prohibition on all forms of unhealthy food advertising online is desirable to protect not only children but also young people and the broader community. Such a prohibition will go one step towards addressing the commercial and digital determinants of health caused by harmful industries' use of online automated advertising.