Make sure you get your greens(pace)

By Hannah Jarman-Miller

Laurelhurst Park is one of my favorite places in Portland. Once the site of a prestigious cattle farm, the area was sold to the City of Portland in 1911 when the east side neighborhoods were beginning to develop and the land became too valuable for agriculture. The area was converted into a public park, intentionally designed to serve the needs of the growing community, which it has continued to do for many generations. It was even named the most beautiful park on the west coast in 1919, and though it may not hold this title in 2017, it is still one of the most beautiful parts of my day.

There is something remarkable and ineffable about the effect that green spaces have on our lives. Not only parks, but the trees that line our streets, the flowers planted near the bus stop, or the looming rhododendrons sprouting up by the side of a building on your way into work. The value of being outside, how refreshing and calming it can feel, is rooted in its proximity with nature. However, with more and more of the world’s population moving into big cities, our outside experiences are being stripped of their greenery. It is essential that we preserve that closeness, because the impacts on our lives, and our health, are substantial. Green spaces have been suggested to improve both perceived and objective health and wellbeing, reduce income related inequality in health, and be a major component of sustainability in urban environments[i]. It has been suggested that many cities need to increase their green spaces as a public health agenda[ii]. More than this, green space has a significant influence on the next generation, in ways that we may not have originally anticipated.

 One recent study conducted in Portland investigated whether greater tree-canopy cover is associated with reduced risk of poor birth outcomes, such as low weight at birth and preterm deliveries, the results of which demonstrated a potential link between the natural environment and pregnancy outcomes[iii]. These outcomes have a significant impact on the continuing health of the child. Since this study was conducted, other research has followed that found protective associations by green space on birth outcomes[iv], and that increased residential greenness was association with beneficial birth outcomes[v]. It is becoming ever more apparent that natural spaces are important to our health, and that the mechanisms by which these benefits are delivered are still being determined.

There are a few proposed explanations for this link between green space and positive pregnancy outcomes. One possibility is that gathering in our communal green spaces leads to increased social support, stronger social networks, and a greater sense of community belonging4. Green spaces also lead to increased physical activity, and reduce noise and air pollution levels1, as well as reducing levels of prenatal physiological stress3. In Japan, “forest bathing”[vi] is recommended as a way to strengthen the human immune system. Most likely of all, is that there are a number of these mechanisms occurring simultaneously. The network of factors by which green spaces are incorporated into our lives and health is intricate, and the extent of influence is yet to be discovered. When we consider the value of green spaces to our communities, and to our next generations, we cannot underestimate their impact.

Laurelhurst Park was built in response to the needs of a growing community, and its benefits are still felt generations later. The same is true in a quite literal sense for the generations to come, as we discover the complexity and strength of the relationship between green space and birth outcomes. Defending green spaces in urban areas is a critical role for public health in urban planning. Considerations that we need to make for the importance of incorporating green space into our built environment has been discussed at previous IMCL Conferences, and will again be discussed at the Santa Fe conference. For example, Anirban Adhya, Associate Professor at Lawrence Technological University, will be presenting The Detroit Conrail Greenway: A case of urban wilderness and placemaking, and Emmalee Dolfi and Bob Heuer from The Trust for Public Land will be presenting the new US-wide survey of accessibility of parks, especially focusing on underserved neighborhoods, and strategies to improve their accessibility and positive health benefits.

[i] Dadvand, P., de Nazelle, A., Figueras, F., Basagaña, X., Su, J., Amoly, E., ... & Nieuwenhuijsen, M. J. (2012). Green space, health inequality and pregnancy. Environment international, 40, 110-115.

[ii] Nieuwenhuijsen, Mark, et al. Fifty Shades of Green. Pathway to Healthy Urban Living. January 2017 - Volume 28 - Issue 1 - p 63–71

[iii] Donovan, G. H., Michael, Y. L., Butry, D. T., Sullivan, A. D., & Chase, J. M. (2011). Urban trees and the risk of poor birth outcomes. Health & place, 17(1), 390-393.

[iv] Ebisu, K., Holford, T. R., & Bell, M. L. (2016). Association between greenness, urbanicity, and birth weight. Science of The Total Environment, 542, 750-756.

[v] Hystad, P., Davies, H. W., Frank, L., Van Loon, J., Gehring, U., Tamburic, L., & Brauer, M. (2014). Residential greenness and birth outcomes: evaluating the influence of spatially correlated built-environment factors. Environmental health perspectives, 122(10), 1095.