As children, many of us instinctively understood that being outside in nature and getting active was, well, simply the best! Now as adults, we can even turn to scientific evidence to see how exposure to green vegetation can profoundly and positively impact our health.
In one study looking at 108,630 women for 8 years, it was found that women living in the top 20% of “average greenness” had a 12% lower rate of all-cause, non-accidental mortality. This was compared to women in the bottom 20%, with the greenness level measured within 250 meters of their homes. These results were weaker, but still consistent, when the level of green cover within 1250 meters was measured.
The association between vegetation and reduced mortality was strongest in the cases of cancer, respiratory diseases, and kidney disease, which fell by 13%, 34% and 41%, respectively. However, exposure to greenery did not protect against coronary heart disease, diabetes, or infections, and its effect against stroke was too weak to be significant.
How Could Nature Protect Against Disease?
So how does this work? For thirty years, a hypothesis of “biophilia” has been proposed, which means that we have evolved to prefer favorable natural environments, i.e. those with plenty of vegetation and water. More specifically, living in said environments can increase physical activity, reduce exposure to pollution, improve social engagement, and reduce stress and depression.
Vegetation can remove harmful air pollution from the air, such as particulate matter, carbon monoxide, and sulfur dioxide. And honestly, how would you rather exercise? By walking or cycling down a crowded city street, cars and buses speeding (or crawling!) past, or in a park where you can hear the birds sing? Where would you choose to meet friends, or go to relax?
The women in this study weren’t exactly young, either. They had initially signed up for the Nurses’ Health Study in 1976, when they were between 30 and 55. This means that from 2000 to 2008, they were aged anywhere from their 60’s to their 90’s! Deaths are usually more difficult to prevent at these ages, so the power of nature is nothing to laugh at.
Green space may also prevent another major threat to the longevity and health of older people: cognitive decline. Amber Watts, an assistant professor of clinical psychology, found in 2014 that daily walking slowed cognitive decline even in people with Alzheimer’s-related pathology. This required their communities to be “walkable,” and a sizeable part of this protective effect came from the mental exercises provided by spatially complex neighborhoods.
There is more than enough research (and personal experience) showing how beneficial nature can be; it’s just about time we unplug ourselves from this crazy world and boost our collective health in the green grass and blue skies.