The Health Impacts of Green Urban Design

By Sarah Titcomb

(Example of a "high-complexity" street with greenery and a variety of facades. Photo Source: Tony Webster from San Francisco, CA.)

A new study has come out that once again links human health to environmental factors. The researchers wired subjects up with stress reading devices that measured the heart rate, brain waves, and body temperature of each individual. The devices were also able to ask the subjects questions as they walked around different cities. According to researchers, there are two types of urban environments, low-complexity and high-complexity. Low-complexity landscapes are, for instance, streets full of unending large corporate buildings that lack any interesting architectural features. High-complexity areas on the other hand, have a diversity of architectural styles and facades, smaller shops mixed with larger buildings, and plenty of urban green spaces.

Data from the study illustrates that when people walk around low-complexity parts of cities they became bored, versus engaged and happy while walking through high-complexity streets. Below, one of the researchers explains how this state of boredom and lack of stimulation can actually be bad for your health.

"The [low-complexity landscapes] produce stress...We generate stress hormones like cortisol that has been related to a number of different kinds of diseases, cardiac diseases, for example. So we know that high levels of cortisol make us less healthy. So if you put all of that together, what it means is, when you're thinking about how to design a streetscape in a city, it's something that goes beyond actual aesthetics. I think that it's a matter of public health to design a city right" (MyNorthwest.com).

This is a statement that jives perfectly with the vision and beliefs of the ROSS. When you have robust and accessible green infrastructure within cities, individuals have the opportunity to become healthier through mental restoration as well as physical activity. The researcher went on to say that, "When you immerse people in a natural setting, you get this immediate and very deep relaxation response from people...It changes the way your body works, it slows down your heart, it reduces those levels of cortisol. It makes you feel happier, it makes your mind work differently. It makes you pay attention to the world in a different way. What's really important for people to understand is we don't have to go off on a trekking holiday in the deep woods to experience those kinds of effects. You can get them from a brief exposure to nature in an urban setting, so a walk through a community garden" (MyNorthwest.com).

While this 2016 study does not address the duration of this benefit, a 2014 study based in the UK did find that living in, or moving to, greener urban environments can produce lasting improvements to your mental well-being. Further, when you move to a greener neighborhood the benefit is almost immediate, and lasts for at least three years (EurekAlert). Although, this lasting improvement may not be equal across the genders. A 2013 study in Scotland once again found that there is "a significant and negative relationship between higher green space levels and stress levels, indicating living in areas with a higher percentage of green space is associated with lower stress" (Roe et al., 2013). But they found that this benefit is not the same for men and women, and varies particularly among the types of green spaces. Additionally, when people move away from greener areas, the effect is not necessarily the opposite of moving to areas with more urban green space. The 2014 study found that when individuals move to more built up locations, they suffer a decrease in mental health right before the move. Although after the move is over, they are able to recover to previous mental health levels.

These studies all highlight the essential services provided by green spaces, as well as the list of things we do not fully understand yet.