Experts say Australian national parks are worth about $145 billion in health benefits.

New research estimates the health value of national parks worldwide to be about $8.7 trillion a year, coming in the form of improved mental health of visitors.

Using a concept called quality-adjusted life years, which measure a person’s ability to carry out the activities of daily life free from pain and mental disturbance, researchers estimated the economic value of national parks using data collected from a representative sample of the Australian population.

For Australia, the team estimated the annual health services value of Australia’s national parks was around $145 billion a year.

“The article suggests several ways to calculate health services value, and these numbers are from just one of those methods - now we need to extend that research to other methods and other countries,” says Griffith University’s Professor Ralf Buckley.

“Protected areas are there for conservation, which gives us a liveable planet and underpins our entire economy, but conservation is not very powerful politically. People and politicians pay more attention to health, because it affects them personally.

“This value already exists, it just was not recognised. People already visit parks to recover from stress. In healthcare terms, it’s patient-funded therapy. Without parks, costs of poor mental health in Australia would rise by $145 billion a year.”

Currently, the costs of poor mental health in Australia amount to approximately 10 per cent of GDP, and the researchers’ estimates indicate that these costs could be 7.5 per cent higher without protected areas such as national parks.

The health-related benefits of spending time in nature are thought to include improved attention, cognition, sleep and stress recovery, but the economic value of national parks is in terms of their impact on the mental health of their visitors has been previously unknown.

“The next step will be to test how mental health benefits depend on individual personalities, and on particular aspects of park visits,” said fellow researcher Dr Ali Chauvenet.

“It’s possible that park visits could then become a routine part of the healthcare system, prescribed by doctors and funded by insurers.

“From a park management perspective, it means that maximum economic return to government treasuries may be from investing in low-key hiking tracks, lookouts, and other visitor facilities, to attract people to visit with their children as often as possible.”

The study is accessible here.