People who live near islands of greenery are biologically, on average, two and a half years younger than the rest, according to research published Wednesday in the scientific journal Science Advances.

In the city, parks and green spaces help to cool down the temperature and promote biodiversity but also help to slowing cell aging.

“Living near greenery helps keep us younger than our actual age,” explained Kiesoo Kim, lead author of the study and a postdoctoral researcher in medicine at Northwestern University.

“We believe our discovery will have important implications for urban planning in terms of expanding green spaces, promoting public health and reducing health disparities,” he added.

It had already been identified link between being green and people’s better cardiovascular health, as well as lower mortality rates. The researchers estimated that physical exercise and social contacts in the parks played a role in this direction. But until now it was not clear that the parks themselves slow down the aging of cells.

Inequalities

Kim and her colleagues more than 900 people attendedwhites and blacks, in four American cities (Birmingham, Chicago, Minneapolis and Oakland) over a period of 20 years, from 1986 to 2006.

With the help of satellite images, the team measured the distance between the participants’ homes and green spaces. He also looked at blood samples taken from participants in the 15th and 20th year of the study to determine their biological age.

The researchers then built scientific models to evaluate the results and took into account various variables that could affect them, such as education, income, whether they are smokers or not, etc.

They observed that people whose homes had around 30% green space within five kilometers were on average 2.5 years younger biologically than those with around 20% green space.

However, the benefits were not the same for everyone.

Blacks who lived near green were only a year younger than their actual age, while whites were three years younger.

“Other factors such as stress, the quality of green spaces and various social factors may affect the benefits”Kim explained, adding that these differences should be examined by other research.

For example, people living in deprived areas avoid frequenting the parks there, as these are often used for illegal activities. Consequently their health benefits are smaller.

Next scientists may examine the connection between green spaces and specific human health consequences, Kim noted. How green slows aging isn’t yet clear, he explained, adding that we just know there’s a connection between green and youth.