Ultra-processed foods (UPFs) are often perceived as low-cost, convenient dietary options. Their industrial manufacturing processes facilitate mass production, reduce costs, and prolong shelf life. A prevailing perception is that healthier, minimally processed diets are more expensive than diets rich in UPFs. This study compared the costs of predominantly ultra-processed (80% of energy from UPF) and minimally processed (20% of energy from UPF) dietary patterns aligned with the Australian Guide to Healthy Eating and assessed the influence of supermarket choice and socioeconomic location on affordability. A cost-comparative design was used to evaluate two dietary patterns for a hypothetical Australian family of four, comprising two adults aged 30–44 years and two children aged 9–11 years, living in low- and high-socioeconomic areas as classified according to the Socio-Economic Indexes for Areas (SEIFA). Both dietary patterns were modelled using serving sizes from the Australian Guide to Healthy Eating. Meals were developed using FoodWorks, with foods classified according to the NOVA classification system(1) as predominantly ultra-processed or minimally processed. Food prices were collected over four weeks from the online platforms of Aldi and Woolworths in low- and high-SES locations. The lowest-cost suitable product within each food category was selected based on price per 100 g. Weekly food costs were then calculated to compare the affordability of the two dietary patterns across supermarkets and socioeconomic areas. Across 14 energy-matched days, the High-UPF diet cost a mean of $52.60 per day for a family of four, compared with $48.85 for the Low-UPF diet. This $3.75 difference was not statistically significant, t(13) = 1.23, p = 0.242, 95% CI [-$2.86, $10.36], d = 0.33. Daily costs were more variable for the High-UPF diet (SD = $12.97 vs. $7.92). Aldi was significantly less expensive than Woolworths for the High-UPF diet (p = 0.015), although this difference was not significant for the Low-UPF diet (p = 0.064). When matched for energy and nutritional adequacy, minimally processed and ultra-processed diets were comparable in food costs, challenging the assumption that whole-food diets are universally more expensive at the product level. The greater day-to-day cost variability of the High-UPF diet suggests that minimally processed dietary patterns may support more predictable household budgeting for Australian families. However, food preparation time, potential savings from bulk buying, and losses associated with perishability were not captured and may influence the overall cost comparison between dietary patterns.
Monteiro CA, Cannon G, Levy RB et al. (2019) Public Health Nutr 22, 936–941.