Consumers attitudes about public health interventions to promote portion control of discretionary food: a qualitative focus group study

Discretionary foods that are energy-dense and nutrient-poor contribute to over one third of total energy intake in Australian children and adults, and the typical portion sizes of many discretionary foods have increased significantly in the last two decades (1) . The portion size norms (described as a typical perception of how much of a given food people choose to eat at a single eating occasion) are likely to have increased concurrently, with larger sizes now being considered the new normal (2) . Public health interventions are urgently needed to reduce the portion size norms and consumption of discretionary foods (3) , but the acceptability of such interventions remains unknown. Therefore, this qualitative study aimed to gain insights into consumers’ attitudes towards potential interventions targeted at promoting portion control of discretionary foods. Four online focus group sessions were conducted via Zoom with healthy Australian adults who regularly consume discretionary foods. A question guide was developed to gather participants’ perspectives around four potential public health interventions; reduction of the default serving sizes, increasing serving size options, changes to package sizes, and improving serving size labelling. A female facilitator moderated all focus groups, with a second moderator present to capture other relevant details. Collected data were analysed using a hybrid approach combining deductive and inductive thematic analyses. A total of 35 participants completed the study (19 females, mean age 38 ± 14 years). Participants identified the current food environment as promoting overconsumption; larger serving sizes were reported to be more ubiquitous and better value for money than smaller size options. An overall positive attitude towards the proposed interventions was noted. Out of the four proposed interventions, participants considered the most acceptable intervention to be providing a wider range of serving size options while maintaining a consistent unit price. Other acceptable interventions included reducing the default serving sizes with concurrent price reduction; education and clear guidance around portion size selection (for example, the involvement of health professionals to promote portion control, along with relevant recommendations of appropriate portion sizes from health authorities); more practical on-pack serving size suggestions; and innovative package designs that enable better portion control without contributing to food and plastic waste. In conclusion, participants identified a need for and were in support of interventions aimed at the portion control of discretionary foods. Further research should focus on examining the feasibility and effectiveness of the potential interventions to reduce the purchasing and consumption of large serving sizes. More efforts from public health authorities are required to develop practical and tailored recommendations for consumers around appropriate portion sizes for discretionary foods. Collaboration with the food industry and policy makers is also necessary for implementing public health interventions to reduce the excessive intake of discretionary foods.