“The exposome encompasses the various experiences and exposures faced throughout the lifecourse and can shape health outcomes by causing changes in the human body, including at the cellular and genetic level.”
Telomere health
The study revealed that neighborhood greenspaces such as yards, parks, and other public areas are particularly beneficial to our telomeres. These are repetitive DNA sections situated at each end of a chromosome, playing a crucial role in safeguarding chromosome ends from potential damage.
With every cell division, these telomeres reduce a bit in size. When they become exceedingly short, the cell can no longer divide and ultimately dies.
Biological age
“This makes telomeres important markers of biological age, or how worn down our cells are,” explained study co-author Scott Ogletree. “And we know that many variables – such as stress – can influence how quickly our telomeres wear down.”
Focus of the study
The study was focused on data from the CDC’s National Health and Nutrition Examination Survey (NHANES), which was conducted from 1999-2002.
The researchers analyzed data from 7,827 individuals, taking into account factors like their demographic details, telomere length, and residence. They evaluated the neighborhood greenspaces in each person’s vicinity and related this information to telomere size.
What the researchers learned
According to Hipp, the findings show a direct correlation between increased neighborhood greenspace and extended telomeres. This correlation was found regardless of an individual’s racial background, economic status, drinking or smoking habits.
“That’s the good news,” said Ogletree. “However, when we accounted for other characteristics of each neighborhood – air pollution, segregation, or ‘deprivation’ – the positive effect of the greenspace essentially disappeared.”
“Deprivation, in this context, was an overarching variable that included the neighborhood-level data on income, education, employment status, and housing conditions. In other words, while greenspace seems to help protect telomere length, the harm from other factors appears to offset that protection.”
Study implications
“Greenspace is tremendously valuable for a community, but it is not enough to overcome systemic racism and the effects of economic segregation and environmental justice challenges on its own,” said Hipp.
“This study drives home the idea that creating greenspace in a community is important, but it’s as crucial – or more crucial – for us to address environmental harms, particularly those tied to systemic racism.”
The research is published in the journal Science of The Total Environment.