Planting trees could help this city prevent 400 premature deaths

Increasing tree cover in Philadelphia could save hundreds of lives, a study says.

(CNN)Many cities around the world are planting trees as a way to fight climate change.

But they might also reduce our risks of dying early.
Scientists say these trees, and other ways to green urban areas, could be just as beneficial to our mental and physical health and reduce the risk of premature death.
    New research has put a number on just how many premature deaths could be prevented in one US city if it were to increase tree cover from 20% to 30% within five years.
    Philadelphia, America's fifth-largest