
The Portland-Vancouver region is the epicenter of a movement to reshape cities into places that promote healthier living and stronger communities. The relationship between health and nature has been documented since the early 1980s, and new research is popping up almost weekly demonstrating the connections.
Here's what we know for sure. Nature affects health in four main ways:
- It encourages green exercise.
- It reduces stress.
- It creates a healthy environment.
- It builds community connections.
GREEN EXERCISE can be as simple as walking, biking or playing sports in a park or on a trail – or as challenging as climbing Mt. St. Helens. Whatever activity you choose, it may be more beneficial than you think. Most green spaces are free, or at least very inexpensive compared to gym memberships. And research shows that the same exercise, when done in nature, gives more than benefits than when done inside, a gym or otherwise. Also, youth regularly exposed to green spaces are more likely to engage in physical activity in general.
Green exercise can reduce blood pressure and burn calories, while increasing strength and metabolism. It can have a positive impact on self-esteem. It can lower the risk of stroke, heart attack, diabetes and so many other health issues that plague our society.
"Potential health gains of a shift from private motorized transport to walking, cycling and rapid transit/public transport include reduced cardiovascular and respiratory disease from air pollution, less traffic injury and less noise-related stress."
– World Health Organization
More and more, it seems that STRESS in America is on the rise. Why is this a problem, besides the obvious ways it is unpleasant? Research shows that stress contributes to heart disease, asthma, obesity, diabetes, headaches, depression, anxiety, gastrointestinal problems, Alzheimer’s disease, accelerated aging and premature death. But here's the good news: a recent Harvard survey reports that spending time outdoors was ranked highest among strategies for reducing stress. In fact, studies show a decrease in stress-related symptoms after just 5 minutes outside, or even from looking at a photograph of nature.
With depression currently ranking as the number one cause for disability, exposure to nature could mean a huge savings in terms of health care and work productivity. Spending time in urban woodlands and park has been shown to increase feelings of restoration, vitality, positive moods and creativity. In fact, individuals who have moved to greener areas have been shown to see an improvement in mental health within 5 years. People living in greener neighborhoods are at reduced risk for sleeplessness, and one study found a lower rate of chronic disease in individuals with access to a park.
A HEALTHY ENVIRONMENT contributes significantly to healthy individuals. Chronic respiratory disease is the fourth leading cause of death in the world, and research shows that air quality plays an important role in its development. Trees and other plants are effective in reducing carbon dioxide, nitrogen dioxide, and other people-harming gases from the air. Also, reducing storm water run-off by adding green infrastructure can eliminate or decrease chances of sewage overflow. By protecting our environment and keeping it clean, people are more freely able to enjoy rivers, forests and parks.
“The idea that physical space might contribute to healing does, it turns out, have a scientific basis. The first study to tackle this question, published in Science magazine in 1984, showed that when hospital rooms have windows looking out on the natural world, patients heal more rapidly."
– Professor Roger Ulrich, Department of Architecture and Centre for Healthcare Architecture, Chalmers University of Technology in Sweden
A green environment also helps build COMMUNITY CONNECTIONS. Research shows that people living in neighborhoods with nearby parks and trails are more likely to know their neighbors, experience a sense of belonging, and feel safer compared to those without green spaces nearby. This results in an increased sense of well-being and more civic participation. Evidence shows that if a park is within close proximity, people are more likely to use it -- adding “eyes on the street,” a concept linked to safer communities. Residents with greener surroundings report lower levels of fear, fewer incivilities and less violent behavior.
A number of local studies confirm the strong relationship between the built environment and a healthy quality of life. Clark County, Washington, conducted a Health Impact Assessment in 2011 to analyze and evaluate the potential public health effects of implementing the Clark County Bicycle and Pedestrian Master Plan. Metro, Multnomah County and the nonprofit Upstream Public Health have undertaken similar studies. Considering the significant costs to society associated with reduced physical activity, it's crucial that our region continue to implement its vision for incorporating nature into our cities.
“It is not surprising that Nature is a source of health and well-being. She has been our source of sustenance, shelter, livelihood and rest for all of human history. She is our ancestral home and the 'baseline' that all life (including our human species) has become accustomed to, despite the recent addition of asphalt, concrete and digital screens. We do better in our bodies, in our minds, and in our communities, when we have a regular relationship with the restorative and healing power of the natural world."
– Kurt Beil, ND, MSOM, MPH, National College of Natural Medicine, Portland

- Percentage of Portland Metro region’s population obese or overweight: 62%
- Estimated deaths in Oregon due to obesity & obesity-related illnesses: 1,500 annually
- Estimated regional healthcare expenditure on obesity: $1 billion annually
- Estimated amount of avoided weight gain due to exercise throughout The Intertwine: 17 million lbs a year
- Regional healthcare savings as a result of physical activity in The Intertwine: $155 million annually
- Regional healthcare savings associated with trees reducing nitrogen dioxide from air: $7 million annually
- Savings in direct medical costs for each $1 invested in trails: $3.60 (according to a study in Lincoln, Nebraska)
- Water caught by The Intertwine's 261,000 sq. miles of pervious surfaces: 168,514 billion gallons annually
- Percentage of days in 2013 that air quality was "good" or "moderate": 96%
- Each 40,000 sq. ft. of green roof removes 1,600 lbs. annually of particulate matter from the air, which yields $3,024 annually in avoided healthcare costs.
- Clean Water Services planted 700,000 native trees at a cost of $6 million, saving rate payers more than $100 million.
HEALTH & NATURE PRESENTATIONS
On May 8, 2014, The Intertwine Alliance and the Institute for Sustainable Solutions at Portland State University co-hosted The Intertwine's first Community Health and Nature Forum. Check out the forum summary or various speaker presentations below.
Read more about The Intertwine Alliance's Health & Nature Initiative.
A big thank you to Intertwine Alliance researcher Lyndsey Boyle of Portland State University for compiling this report.