PARIS, Nov 29 — Living in a neighbourhood with lots of trees could play a role in increasing the life expectancy of residents, reports a recent study conducted in the United States.
The benefits of gardening are already well-known, and regular contact with nature has been found beneficial to physical and mental health. In the same vein, a neighbourhood that benefits from a long-term “green restoration” policy could have similar virtues.
In fact, the impact could be significant, since this could actually boost the life expectancy of an area’s residents, according to research conducted in the United States.
Published in the journal Environment International, and co-led by the Barcelona Institute for Global Health (ISGlobal), the study draws on scientific literature to investigate associations between exposure to nature and reduced mortality.
The research is based on the work of the American NGO Friends of Trees, which planted 49,246 trees in the streets of Portland, a city located in the state of Oregon, between 1990 and 2019.
The research team examined the number of trees planted in a specific area (with a population of about 4,000) over the previous five, ten or fifteen years.
They then associated this information with mortality from cardiovascular, respiratory, or non-accidental causes in that same area, using data from the Oregon Health Authority Registry.
The results show that in neighbourhoods where more trees were planted, mortality rates (deaths per 100,000 people) were lower.
According to their findings, each tree planted was associated with a significant reduction in non-accidental and cardiovascular mortality (by 20 per cent and 6 per cent respectively), particularly among men, as well as among people over 65 years of age.
The study authors also note that the mortality rate was twice as low if the trees had been planted 11 to 15 years earlier.
This observation makes sense to the researchers, since large trees are better able to counteract mortality factors such as air pollution, rising temperatures and noise.
“We observed the effect both in green and less green neighbourhoods, which suggests that street tree planting benefits both,” says Geoffrey H. Donovan, from the USDA Forest Service and first author of the study. — ETX Studio
