The high availability of energy-dense nutrient-poor discretionary foods in large serving and package sizes may have shifted portion size norms (described as a typical perception of how much people choose to eat from a given food at a single eating occasion) towards larger sizes. Few public health recommendations exist around appropriate discretionary food portion sizes. This qualitative study aimed to explore the underlying rationale of portion size norms of discretionary foods among Australian adults 18–65 years.

Four focus group sessions were conducted. Collected data were analysed using inductive thematic analysis.

Focus groups were held online via Zoom between September and October 2023.

Thirty-four participants were recruited in the study (mean age 38 years, 19 females).

The key themes raised from inductive analysis were personal factors, eating context factors and food environment factors relevant to the portion size norms. A framework was established to illustrate the interaction across these themes during the conceptualisation of the norms. For serving size availability, consumers found that there were limited serving size choices when making portion size selections and lacked the knowledge and skills in portion control.

These findings highlight the need to make positive changes to the current food environment and develop relevant public health guidelines around appropriate portion sizes to promote healthier portion size norms and enable better portion control.

Agriculture accounts for around 70 % of global freshwater withdrawals. As such, the food system has been identified as a critical intervention point to address water scarcity. Various studies have identified dietary patterns that contribute less to water scarcity. However, it is unclear what level of reduction is necessary to be considered sustainable. The pursuit of unnecessarily aggressive reductions could limit dietary diversity. Our objective was to assess the sustainability of water use supporting Australian dietary habits and the adequacy of current dietary guidelines.

Dietary intake data were obtained from the National Nutrition and Physical Activity component of the Australian Health Survey. For each individual daily diet, the water scarcity footprint was quantified, following ISO14046:2014, as well as a diet quality score. Water scarcity footprint results were compared with the planetary boundary for freshwater use downscaled to the level of an individual diet.

Australia.

9341 adults participating in the Australian Health Survey.

Dietary water scarcity footprints averaged 432·6 L-eq (95 % CI 432·5, 432·8), less than the 695 litres/person per d available to support the current global population of 7·8 billion, and the 603 litres/person per d available for a future population of 9 billion. Diets based on the Australian Dietary Guidelines required 521 L-eq/d, or 379 L-eq/d with lower water scarcity footprint food choices.

Diets based on the Australian Dietary Guidelines were found to be within the freshwater planetary boundary. What is needed in Australia is greater compliance with dietary guidelines.

The present research aimed to investigate the impact of the physical activity calorie equivalent (PACE) front-of-pack label on consumption, prospective consumption and liking of familiar and unfamiliar discretionary snack foods.

In a within-subject randomised design, participants tasted and rated liking (9-point hedonic scale) and prospective consumption (9-point category scale) of four different snack foods with four different labels (i.e. blank, fake, PACE, PACE doubled) and four control snack foods. The twenty snack foods were presented during two 45 min sessions (i.e. ten snack foods per session) which were separated by one week. The amount participants sampled of each snack food was measured.

The study was conducted in the Centre for Advanced Sensory Sciences laboratory at Deakin University, Australia.

The participants were 153 university students (126 females, twenty-seven males, mean age 24·3 (sd 4·9) years) currently enrolled in an undergraduate nutrition degree at Deakin University.

When the PACE label was present on familiar snack foods, participants sampled 9·9 % (22·8 (sem 1·4) v. 25·3 (sem 1·5) g, P=0·03) less than when such label was not present. This was in line with a decreased prospective snack food consumption of 9·1 % (3·0 (sem 0·2) v. 3·3 (sem 0·2) servings, P=0·03). Such pattern was not seen in unfamiliar snacks.

The PACE label appears to be a promising way to decrease familiar discretionary snack food consumption in young, health-minded participants.

Excessive consumption of discretionary foods/beverages in the Australian population has been identified, increasing the risk of obesity and chronic disease. The present study aimed to examine the associations between demographic, anthropometric and dietary factors and the consumption of discretionary foods, discretionary beverages and discretionary foods/beverages combined.

Discretionary food/beverage consumption reported in two 24 h recalls was analysed, stratified by gender, age, socio-economic status, country of birth, BMI, waist circumference, and fruit and vegetable intakes.

2011–12 National Nutrition and Physical Activity Survey.

Australian adults (n 7873) aged 19 years or above.

Mean discretionary food and beverage consumption was 631 g (28 % by weight from foods; 72 % from beverages), providing 2721 kJ of energy intake (72 % from foods; 28 % from beverages). Total discretionary food/beverage consumption was higher in younger age groups (P<0·001), those in lower socio-economic categories (P<0·001), those born in Australia (P<0·001), those with higher BMI (P<0·001) and those with lower fruit (P<0·001) or vegetable intake (P<0·001). Discretionary beverage consumption (β=6·6, P<0·001) was more strongly associated with BMI than discretionary food consumption (β=0·5, P=0·01).

Total discretionary food/beverage consumption as well as discretionary foods alone and discretionary beverages alone were associated with BMI in Australian adults. In addition, high intakes were associated with younger age, lower socio-economic status, and lower consumption of fruit and vegetables.