Discretionary food intake and willingness to change in a large Australian cohort: findings from the CSIRO Junk Food Analyser

Discretionary foods and beverages (DF) contribute around one third of daily energy intake in Australian adults.⁽¹⁾ The National Preventive Health Strategy 2021–2030 prioritises a reduction in energy from DF to improve diet quality and reduce the burden of non-communicable disease and obesity.⁽²⁾ In April 2021, CSIRO launched the ‘Junk Food Analyser’, an online survey allowing Australians to assess their DF intake. This study uses data collected from the survey to describe the DF intake of Australian adults, and what and how they are willing to change. Cross-sectional data were collected in the 4 weeks after launch. Participants included Australian adults ≥ 18 years, with a BMI ≥ 18.5 kg/m², who exceeded age and gender specific Australian Dietary Guideline recommendations for DF.⁽³⁾ DF were grouped into 11 categories based on the Australian Dietary Guidelines. Intake was assessed using frequency and portion-based questions, with intake converted into serves per day. Participants indicated their willingness to consume less of DF categories on a five-point scale (5 = very willing). Median (IQR) willingness per DF category was calculated across the cohort consuming that category. Participants were asked to indicate which strategies they would be willing to attempt to reduce their intake of their most consumed category of DF from ‘eliminate’, ‘halve’, ‘days off’, ‘fewer types’ and ‘healthy swaps’. Of 42,327 survey completions, 27,694 (65.4%) participants met the criteria, 71.2% being female, 53.0% aged ≤ 50 years, 55.7% university educated and 66.9% with overweight/obesity. DF intake was a median of 5.0 serves/day (IQR = 3.6–7.3). Alcohol, followed by cakes and biscuits, confectionary, and takeaway were the most consumed categories of DF (by intake in serves). Willingness to reduce intake was highest for takeaway foods and savoury pastries (4, 4:5) and lowest for alcohol (3, 2:4). In all categories except takeaway, willingness to reduce the most consumed category was lower than participants mean willingness across remaining categories. The most acceptable strategy was ‘days off’, particularly with respect to alcohol (58.6% of consumers with alcohol as their most consumed category), confectionary (47.0%) and ice-cream (40.7%). Strong survey engagement demonstrates public interest in DF intake. Strategies for reducing DF intake that target frequency of consumption such as having ‘days off’, rather than strategies targeting portion size, appear to be preferred. People's worst area of consumption may be the most resistant to change. It is therefore important to consider not just what Australians need to change, but also what they are willing to change. Takeaway food appears to be a promising intervention target. Personalised intervention targets may be beneficial, but these may also need to focus on behaviours that are less habitually ingrained and more open to change. This could involve a sequential intervention approach, addressing foods less consumed first to build incremental feelings of success.