Food Processing Knowledge in Relation to Healthiness and Self-Reported Understanding of the Health Star Rating in...

This study aimed to examine Australians' food processing knowledge in relation to food healthiness and self-reported understanding of the Health Star Rating (HSR), their association, and sociodemographic differences.

An online survey was completed by 3760 adults in Australia as part of the 2021 International Food Policy Study. Participants rated the healthiness of foods across four categories (grains, meat, dairy, fish), with three products presented per category representing increasing levels of processing. Food processing knowledge (FoodProK) scores were based on the alignment between healthiness ratings and processing level. Participants also self-reported their ease of understanding the HSR. Multivariable regression analyses were conducted.

The mean FoodProK was 4.8 (of 8 points); 63% of respondents found the HSR label very easy/easy to understand. FoodProK was positively associated with HSR understanding. Females and older respondents had a higher FoodProK, while those aged 60+ had lower HSR understanding. Respondents who identified as Aboriginal and/or Torres Strait Islander had a lower FoodProK and HSR understanding. Following dietary restrictions and not being involved in food shopping were associated with lower FoodProK. Higher self-reported nutrition knowledge, diet healthiness and income adequacy were associated with higher FoodProK and/or HSR understanding.

The study found a moderate FoodProK, a generally adequate HSR understanding, and a positive association between self-reported HSR understanding and food processing knowledge in relation to food healthiness, although notable sociodemographic inequities were observed.

Tailored communication strategies may help improve understanding of the HSR and food processing in relation to healthiness across population groups.