Northwestern Professor Teresa Horton hopes people will spend more time in nature. (Submitted photo)

After a 50-minute walk in the park, a person’s mood improves and their cognitive function increases, according to a 2019 study in a body of work called the Walking Green Project. And people who spend more time outside tend to have better mental health, recent research shows.  

However, these studies do not prove that regular exposure to nature directly leads to an improvement in heath conditions like cardiovascular disease, diabetes, and obesity. That’s what Northwestern professor Teresa Horton’s research is centered around. She is working to find data that shows the long-term benefits of spending time in nature, particularly when it comes to alleviating stress.  

“Chronic stress changes our neurotransmitters. It changes our stress hormones, and it leads to chronic illness,” said Dr. Horton. “How can we change our urban plans? How can we make nature available as a place of refuge for people to help break the cycle of chronic stress?”  

Dr. Horton had to sift through confounding variables in order to understand the impact that nature alone has, she said. Exercise and exposure to sunlight have proven beneficial to health, but Dr.  Horton is working to understand nature’s influence apart from these factors.  

For instance, Dr. Horton and fellow researchers have shown a distinction between exercising in nature and exercising in an urban or indoor setting, according to their work in the Walking Green Project.

“If you’re doing your exercise in a green space, you are more relaxed and less stressed than if you tried to do it on a suburban sidewalk,” Dr. Horton said. She points to a study that shows the sounds of nature can decrease stress-levels and another study that shows looking at the patterns in nature has a calming effect.  

“We need to step back and take a more holistic view of health and our relationship with nature,” Dr. Horton said. “Our human connections with nature can contribute to public health and to our general health, from physical to mental health.”  

Dr. Horton is also conscious of the disparities between natural spaces. Spending time outdoors in areas with poor air quality and heavy pollution can lead to negative health effects, she said. 

In addition, not all natural spaces are accessible. Particularly in Chicago, low-income and minority communities have fewer green spaces, said Dr. Horton. It is easier for individuals in  wealthier communities to seek medical help and go on relaxing vacations, so those who benefit  most from accessible natural spaces are low-income communities.  

While Dr. Horton’s primary role is researcher and scientist, she said she hopes her findings will encourage policymakers or city planners to prioritize natural spaces. These spaces are also important for furthering sustainability efforts. “The things in nature that benefit our health, our clean air, clean water, stable soils, biodiversity, those are all the hallmarks of a sustainable  ecosystem,” said Dr. Horton.  

The NCH2 Network  

Independent of her research, Dr. Horton is the organizer and chairperson of the NCH2 network, a group working to connect individuals and organizations interested in nature’s effect on health.  

NCH2 was started in 2014 after a symposium organized by the Forest Preserves of Cook County and held at the Chicago Botanic Garden. The symposium, titled “Nature, Culture, and Human Health,” inspired the group’s name. Speakers discussed the benefits of nature in order to encourage more residents to connect with Cook County’s Forest Preserves. The meeting was so successful that attendees wanted to continue to stay in touch. In response, the organizers founded NCH2 in order to help connect those interested in the topic of nature and mental/physical health.  

Many groups have researched the effects of nature on health, but are not in touch with each other, said Dr. Horton. A goal of NCH2 is to bring these groups together and provide them with  helpful resources. Before the COVID-19 pandemic, NCH2 held a symposium every other year. Now, these symposiums have been replaced with virtual coffee dates and occasional larger Zoom presentations.  

Dr. Horton’s Work  

Before organizing the NCH2 network, Dr. Horton, who has a background in biology, studied how organisms adapt to changes in their environment. Around the time that the NCH2 network was started, she began to focus more on the influence of nature on human health. Dr.  Horton said she wanted to take a step back to understand the significance of her work to humans and their relationship with the planet.  

“Anything that we can see, hear, touch, smell, taste, ends up influencing our brain, and can influence our health,” said Dr. Horton. She said people need to start thinking of their skin and sensory organs as a way to connect with the environment, not a barrier that separates them from it.  

A part of Dr. Horton’s research involves evaluating what the correct “dosage” of nature should be. A 2019 study from the United Kingdom shows that people should spend 120 minutes a week in nature.  Dr. Horton would like to go further to understand how that time should be broken up and if this time in nature is having lasting health effects. Even without further study, Dr. Horton recommends people spend as much time as they can outside and that they do their physical activity in nature.  

“Support your local parks and green spaces,” said Dr. Horton. “Get outside as much as you can, and take time to just stop and sit and listen to nature.” 

Adina Keeling

Adina Keeling is a photojournalist and reporter, covering city news, sustainability, schools, and art. She also investigates mental health systems and environmental injustices in Evanston, and puts together...