Evidence is increasing from multiple scientific fields that exposure to the natural environment can improve human health. In a new study by the US Forest Service, the presence of trees was associated with human health.
Report by EurekAlert
For Geoffrey Donovan, a research forester at the Forest Service’s Pacific Northwest Research Station, and his colleagues, the loss of 100 million trees in the eastern and midwestern United States was an unprecedented opportunity to study the impact of a major change in the natural environment on human health.
In an analysis of 18 years of data from 1 296 counties in 15 states, researchers found that Americans living in areas infested by the emerald ash borer, a beetle that kills ash trees, suffered from an additional 15 000 deaths from cardiovascular disease and 6 000 more deaths from lower respiratory disease when compared to uninfected areas.
“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 Donovan. “But we saw the same pattern repeated over and over in counties with very different demographic makeups.”