Magella Lajoie, Sydney Region Branch
Since the COVID-19 crisis, my husband and I head off for the bush at the end of our street everyday. We are very lucky to live in a suburb with abundant greenspace. We have been bushwalkers all our lives and know that feeling of introspection during the walk and value that feeling of rejuvenation after a bush walk. Now science has bourgeoning evidence that urban greenspace is good for our health, our mental health and our wellbeing.
Cities create difficult environments, with poor or turbulent airflows, heat island effects and increased surface water runoff. Well planned urban greenspaces can modify these effects. Urban greenspace can also alleviate adverse factors in the urban environment, such as social inequalities, air pollution, noise, chronic stress and insufficient physical activity. All these factors are known to negatively impact our health. Town planners now have available detailed tool kits for analysis of land use and population data to design for greenspaces to be accessible, large enough to allow exercise, provide for social spaces and be well equipped, eg playgrounds, and to be safe.
The effectiveness of urban greenspace is thought to be through psychological relaxation, stress alleviation, increased physical activity, and reduced exposure to air pollutants, noise and excess heat. Emergency departments across Australia plan their work on hotter days to respond to statistics that have consistently shown increased presentations of self-harm and suicide on hotter days. Air pollution (PM2.5 and PM10) has been associated with other major mental illnesses such as bipolar disorder. One theory is that this small particulate matter enters the bloodstream to cause inflammation in major organs including the brain. Reduced cardiovascular morbidity and mortality, obesity, type 2 diabetes, and improved pregnancy outcomes are some of the physical health benefits of urban greenspace, and therefore have flow-on effects to mental and community health.
Improved school performance, including social skills, improvement in attention and ADHD scores in children have been associated with time in nature and urban greenspace. Wellbeing in children and adults is attributed to reduction in stress, restoration of attention as well as a sense of social cohesion and meaning of life. Exciting recent research indicates that time spent in nature may improve our microbiome thereby boosting our immune system.
What I find heartening is evidence that urban greenspace mitigates the health effects of social inequalities. For example, adolescents from poor areas of New York who suffer from depression have been shown to fare much better if they live near sizeable parks. For decades we have known that social inequalities are the modifiable causes of physical and mental illness and disability. Shockingly, social inequalities reduce lifespan by up to 20 years.
The evidence that health benefits of urban greenspace are strongest most of all for the most vulnerable – economically deprived communities, children, pregnant women and senior citizens – prompted the World Health Organisation, in the Parma Declaration in 2010, to a commitment “…to provide each child by 2020 with access to healthy and safe environments and settings of daily life in which they can walk and cycle to kindergartens and schools, and to greenspaces in which to play and undertake physical activity”.
Readings and contacts
- www.dea.org.au/why-we-need-forests-and-native-vegetation-for-our-health A Doctors for the Environment Australia Factsheet – a concise summary of the many ways our health depends on our forests and greenspace