Food stress has heightened during the pandemic, but new modelling demonstrates how nutritional quality and affordability can be improved.

Dietary modelling in both Australia and New Zealand has identified how nutritional quality and affordability of food could be improved. Foods were categorised by level of processing, analysed for nutrient density as measured by the Nutrient Rich Food Index (NRF9.3), and cost, and ranked by nutrient density-to-cost ratio.

In Australia

The top quartile of nutrient-dense, low-cost foods included:

• 54% unprocessed foods (e.g., vegetables and reduced fat dairy)
• 33% ultra-processed foods (e.g., fortified wholegrain bread and breakfast cereals with <20g sugars/100g)
• 13% processed (e.g., fruit juice and canned legumes)

Fruit juice had the highest nutrient density-to-cost ratio, followed by orange and yellow vegetables and processed potatoes (e.g., oven fries).

Using substitution modelling whereby lower nutrient density-to-cost ratio foods were replaced by foods with the highest nutrient density-to-cost ratio, dietary quality improved 52% for adults and 71% for children across all households, and affordability improved by 25% and 27% for low-medium socioeconomic households, respectively.

In New Zealand

The top quartile of nutrient-dense, low-cost foods included:

• 56% unprocessed foods (e.g., vegetables, fruit, porridge, pasta, rice, nuts, seeds)
• 31% ultra-processed foods (e.g., vegetable dishes, fortified bread, unfortified breakfast cereals with <15g sugars/100g and fortified cereals with 15-30g sugars/100g)
• 6% processed (fruit juice)
• 6% culinary processed oils

The highest nutrient-density-to-cost ratio was achieved by fruit juices, followed by other vegetables, and orange/yellow vegetables. Using substitution modelling whereby lower nutrient density-to-cost ratio foods were replaced by foods with the highest nutrient density-to-cost ratio, dietary quality improved 59% for adults and 71% for children across all households and affordability improved by 20-24%, depending on ethnicity and SES.

Key take out messages

This research suggests the nutritional quality and affordability of diets in Australia and New Zealand could be improved by choosing nutritious, low-cost foods. These include some core foods categorised as ‘ultra-processed’ such as bread and breakfast cereals, and some nutrient-dense foods containing added and free sugars such as breakfast cereals and pure fruit juices.

You can freely access both these papers here (Au) and here (NZ)