Surrounding ourselves with nature does wonders for our bodies, from better mental health to healthier hearts and stronger developing immune systems. So much so that some doctors are literally prescribing nature as treatment.
New research may have found a potential explanation for some of these benefits: People living in areas surrounded by nature tend to have younger biological ages.
“This study was an attempt to quantify the beneficial impacts of greenspace at the cellular level, and the extent to which greenspace can help to offset environmental harms,” says social ecologist Aaron Hipp from North Carolina State University.
Examining 7,827 people and their home environments, the researchers found those living in areas filled with more parks, gardens, trees, and other vegetation had longer telomeres – a region in DNA sequences associated with longevity.
“That was true regardless of race, economic status, and whether they were drinkers or smokers,” explains Hipp.
Telomeres are repeating sections of DNA found at the ends of each of our 46 chromosomes, preventing the genetic molecule from unravelling (like the plastic ends of shoelaces).
Each time a cell divides, the telomeres inside them become shorter, until the cell can no longer divide its genetic material and its cell line dies out.
“This makes telomeres important markers of biological age, or how worn down our cells are,” explains University of Edinburgh geospatial analyst Scott Ogletree.
“We know that many variables – such as stress – can influence how quickly our telomeres wear down.”
Green spaces are well known to mitigate stresses in many ways. Plants help protect and insulate us from the environment, keeping our surrounds up to several degrees cooler during heat waves. They decrease air and noise pollution.
Green spaces encourage physical activity and social interactions and are associated with a lower risk of crime.
Yet at the same time we’ve been learning just how intrinsically reliant our minds and bodies are on the natural world, as we’ve become more segregated from it than ever, in perception as well as in our physical realities.
This disconnection has likely contributed to the deterioration of the natural world around us (the sixth mass extinction), as we’ve lost awareness of what the world around us should be like – a situation related to the phenomenon of shifting baseline syndrome.
While this phenomenon may offer some psychological protection in the short term, it’s also dangerous for our future health, and studies such as this one are now demonstrating the immediate impacts separation from nature has on our health as well.
“Considering the average rate of attrition in the sample, greenspace could reduce a person’s biological age by 2.2 to 2.6 years,” Ogletree and colleagues calculated.
Of course, the powerful benefits of nature only work up to a point. When the team accounted for risk factors such as air pollution, the positive impacts of green spaces disappeared.
Their study also highlighted the impacts of racial inequities in limiting peoples’ access to green spaces. Non-hispanic white people in the study lived in the greenest areas, which tended to have lower racial/ethnic diversity overall.
What’s more, the impacts aren’t as clear when considering women alone, suggesting additional disease risks or added social stresses may be playing a larger role on their telomere length.
The researchers suspect the stresses these other factors contribute may overwhelm the benefits contributed by green spaces.
“Greenspace is tremendously valuable for a community, but it is not enough to overcome systemic racism and the effects of economic segregation and environmental justice challenges on its own,” says Hipp.
“This study drives home the idea that creating greenspace in a community is important, but it’s as crucial – or more crucial – for us to address environmental harms, particularly those tied to systemic racism.”
Even if your neighbourhood is lacking in green space though, we can all find ways to try to reconnect with nature – even if it’s just removing the dust around the house, or by starting a garden on your balcony.
This research was published in Science of the Total Environment.