Public knowledge of ultra-processed foods: Insights from a national survey of Australian adults.

Abstract

Background: Ultra-processed foods (UPFs) are increasingly recognised as major contributors to diet-related chronic diseases, environmental deterioration and cultural impacts. While the salience of the UPF concept in societal discourse has also grown substantially in recent years, public knowledge of UPFs remains unclear. This study aimed to explore public knowledge of, and attributes associated with, UPFs in Australia.

Methods: Data included cross-sectional national survey involving 1,086 adults (20-64 years) living in Australia. Data collection occurred between June and July 2024 using a piloted questionnaire administered via Qualtrics market research services. Sociodemographic characteristics and prior awareness about UPFs were collected. The survey included open-ended questions, free-listing tasks, UPF functional knowledge measures (e.g., identification of UPFs among 20 images of products; Food Processing Knowledge (FoodProK) Score), and triadic sorting techniques (used to identify attributes associated with UPFs). Multivariable linear regression models were fitted to examine associations between the number of items correctly identified as UPFs, and FoodProK scores, with socio-demographic characteristics. Open-ended responses to the main survey question 'What comes to your mind when you think of the term 'ultra-processed foods' were analysed using Leximancer, a content analysis software, to identify dominant concepts and themes. Attributes reported through the triad sorting techniques were thematically analysed.

Results: Sixty-four percent of participants reported awareness of the UPF term. The dominant concepts and themes in participants' responses reflected key characteristics of UPFs (e.g., presence of industrial ingredients) and main examples were fast-food meals and soft drinks. Most participants (85%) were able to correctly identify non-UPFs, and 45% were able to correctly identify UPFs, with multigrain bread and flavoured yoghurt misclassified most often. Socio-demographic differences were observed, with women, people with higher education, Non-Indigenous people and those with prior awareness about UPFs being more likely to correctly identify UPFs. Attributes associated with UPFs included presence of artificial ingredients, low nutritional quality, convenience, and affordability.

Conclusions: In this national survey, most participants were aware of the concept of UPFs and could identify key UPF characteristics, however some UPF items were often misclassified. Future research could explore how UPF knowledge influences diet, the factors shaping this knowledge, and interventions and policies to improve knowledge and reduce UPF consumption.