Study suggests link between trees, human health

US Forest Service study suggests connection between trees, human health


DETROIT – Can't see the forest for the trees?  That could be a good thing when it comes to your health.

A new study by the U.S. Forest Service suggests there may be a connection between the presence of trees and human health.

The researchers came to that conclusion after studying areas, like Michigan, that suffered massive tree loss due to the emerald ash borer, a destructive beetle that kills ash trees.

The study analyzed 18 years of data from 1,296 counties in 15 states.  They found that Americans living in areas infested by the emerald ash borer suffered from an additional 15,000 deaths from cardiovascular disease and 6,000 more deaths from lower respiratory disease, compared to uninfected areas.

The findings held true even after taking into account other factors like income, race and education.

"There's a natural tendency to see our findings and conclude that, surely, the higher mortality rates are because of some confounding variable, like income or education, and not the loss of trees," said researcher Geoffrey Donovan. "But we saw the same pattern repeated over and over in counties with very different demographic makeups."

The study found an association, but didn't prove the lack of trees causes poor health.  Researchers don't know exactly why having trees around is beneficial, but previous studies suggest exposure to nature can reduce stress.