New UofL study reveals health benefits of increased tree coverage in Louisville

LOUISVILLE, Ky. (WDRB) -- A University of Louisville research study reports trees have a positive affect on people's health.

UofL's Green Heart Louisville Project found people living in neighborhoods where the number of trees and shrubs was more than doubled showed lower levels of a blood marker of inflammation than those living outside the planted areas, according to a news release. General inflammation is a risk indicator for heart disease and other chronic diseases.

The project launched by the Christina Lee Brown Envirome Institute partnered with The Nature Conservancy, Washington University, Hyphae Design Laboratory and others in 2018. The study focused on whether and how living among more densely greened surroundings contribute to better heart health.

According to a news release, the team applied the treatment, which was the addition of large trees and shrubs, to some participants' neighborhoods but not to others. The study then compared residents' health data to see how the addition of trees affected their health.

"Trees are beautiful, but these results show that the trees around us are also beneficial to individual and community health. Through this and many other projects, the Envirome Institute is improving health at the community level, not just for individuals, but for everyone living in a neighborhood," UofL president Kim Schatzel said in a news release.

At the start of the study, researchers took blood, urine, hair and nail samples to document health data from 745 people living in the four-square-mile area of south Louisville. The researchers also measured tree coverage and levels of air pollution in the area.

More than 8,000 trees were planted in the designated neighborhoods as people living in the green area were considered treated population.

The study found people living in the greened areas had 13-20% lower levels of biomarker of general inflammation compared to those living in the areas without the additional trees. According to the study, a reduction of hsCRP corresponds to nearly a 10-15% reduction in the risk of heart attacks, cancer or dying from any disease.

"These results from the Green Heart Louisville Project indicate that trees contribute more to our lives than beauty and shade. They can improve the health of the people living around them," Aruni Bhatnagar, director of the Envirome Institute and UofL professor of medicine, said in a news release. "Although several previous studies have found an association between living in areas of high surrounding greenness and health, this is the first study to show that a deliberate increase in greenness in the neighborhood can improve health."

To learn more about the project, visit Green Heart Louisville's website.

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