How inequity leads to poor nutrition

There is evidence that the lower people’s socioeconomic status, the more likely they are to eat a poor diet, putting them at greater risk of chronic disease.

A Prevention Centre project had made a quantum leap in our understanding of why this is so, by examining the inequities in the food system and people’s local environment that encourage poor diets.

Researchers led by Professor Sharon Friel from the Australian National University have developed a systems framework to examine the impact of factors such as price, distribution of retail outlets, and the quality of the food supply on people’s diets. Importantly, the framework moves out of the food system to also include issues such as employment conditions, social welfare levels and urban planning.

Professor Friel said the main aim of the project, known as the Healthy and Equitable Eating (HE²) study, was to bring a social equity lens to systems methods.

“What, where and how much people eat are responses to their economic, environmental and cultural contexts,” Professor Friel said. “We wanted to understand the effects of determinants, social inequities and poverty – what is it that undermines the abilities and desires of different social groups to make use of a healthy food environment when it exists?”

She said evidence on inequities in non-communicable diseases and their risks factors, particularly diet, had not been examined from a systems perspective in Australia before. The team’s paper on their systems methods has been accepted recently by PLOS ONE (pending revisions).

Modelling inequities

The HE² project involved collaborative conceptual modelling workshops with an expert group of representatives from government, non-government health organisations and academia. The workshops developed a visual representation of the determinants of inequities in healthy eating – called a causal loop diagram.

Research Fellow Dr Melanie Pescud said the causal loop diagram demonstrated the complexity of the determinants of inequities in healthy eating.

It highlighted seven sub-systems that influence people’s healthy food consumption: food supply and environment; transport; housing and the built environment; employment; social protection; health literacy; and food preferences.

While some of these sub-systems had been studied in detail elsewhere, this was the first attempt in Australia to understand from a complex systems perspective how individual and societal level factors interacted in a dynamic way.

The project showed that the distribution of healthy eating is influenced by all the sub-systems, and that they each influence each other. For example, housing not only influences healthy eating, but can also influence transport, employment and, food supply and environment.

Dr Pescud said the process had highlighted how all areas of government needed to address social inequity and conditions, not just in the food system, to successfully tackle poor nutrition and chronic disease. “The purpose of doing this was to understand the whole system and to begin to identify key leverage points to more effectively address inequities in healthy eating,” she said.

“To me, it’s reinforced the message that we need to look beyond the food system. This doesn’t get fixed in the Health Department alone.”

The systems framework has led to development of an HE² framework to guide whole-of-government policy actions in these areas.