Visits to green spaces, like national parks, have the potential to save the health system millions of dollars, according to researchers from the University of Adelaide.
Associate Professor Patrick O'Connor and Associate Professor Adam Loch, School of Economics and Public Policy, and Dr Jack Maclean, School of Computer and Mathematical Sciences, have extended upon well-known knowledge that green spaces can have a positive impact on health.
They used mobile phone data to estimate the use of Adelaide's 20 most accessible national parks -- Adelaide International Bird Sanctuary, Aldinga Scrub, Anstey Hill, Cobbler Creek, Torrens Island, Black Hill, Morialta, Cleland, Brownhill Creek, Belair, Shepherds Hill, Marino, Sturt Gorge, O'Halloran Hill, Hallett Cove, Onkaparinga River, Granite Island, Newland Head and Deep Creek National Parks -- in 2018-19.
This data was combined with information from a survey of more than 1,000 park visitors about attitudes towards South Australian parks, as well as the cost of treating 10 of the most major long-term chronic diseases to estimate the health savings, according to Australian Institute of Health and Welfare figures for the state.
The research, published in Urban Forestry and Greening, found Adelaide's 1.3 million residents made around 1.45 million trips to parks, with access to these spaces having the potential to reduce healthcare costs by $140 million a year.
"Spending time in green spaces leads to higher reported levels of wellbeing and general health by contrast to people in the population who do not visit green spaces," said Associate Professor O'Connor.
"This in turn can lead to lower private health costs (visits to a general practitioner) and less reliance on public health services (visits to publicly funded clinics).
"A greater understanding of the health benefits associated with using green spaces can then assist governments to better account for the external costs and benefits across alternative or related options, like investments in different green space infrastructure."
They also analysed the impact of access on socio-economic groups across the metropolitan area, applying the postcode-based Index of Relative Socioeconomic Disadvantage from the ABS.
"Importantly, citizens from the highest 40 per cent of relative socio-economic disadvantage in the metropolitan area received a disproportionately low reduced health cost from accessing nature green spaces, despite the additional private cost of accessing the urban national parks," said Associate Professor O'Connor.
"We found people from the most disadvantaged socio-economic backgrounds live around three times further from metropolitan national parks (large biodiverse areas) and have travel and proximity barriers to getting the health benefits of nature, making access to nature a social inequality problem with significant cost implications."
The study found those within the higher socio-economic areas had a wider selection of parks to choose from, and did visit more often than their lower socio-economic counterparts.
"Lower socio-economic groups are prepared to travel to green spaces, but a concentration of parks at more distant locations - more than 30 km away - may limit the opportunity for these groups to improve their health benefit and reduce costs to the health system."Associate Professor Adam Loch, School of Economics and Public Policy, University of Adelaide
"Lower socio-economic groups carry a higher burden of chronic diseases and associated health costs. These groups will also have a higher probability of needing to rely on the public health system by contrast to higher socio-economic groups," said Associate Professor Loch.
"And yet when the lower socio-economic groups use green spaces, they may improve their health; again, at a higher relative rate to other groups as might be expected and in line with other jurisdictions.
"The fact that many green spaces are also increasingly the main way in which many of us interact with natural settings - and experience the outdoors - as urban migration grows over time, the importance placed on preserving them for current and future generations increases.
"More work needs to be done to show where health budgets can be reduced by investments in access to nature."
