A new study is finding that greener neighborhoods protect telomeres from being damaged.
The role of telomeres in aging
Telomeres are repetitive sequences of DNA found at the ends of chromosomes that play a crucial role in preserving the integrity and stability of the genetic material within a cell.
As cells divide and their telomeres become progressively shorter, they eventually reach a critical point where they can no longer divide. This state is known as cellular senescence, and it is associated with aging and age-related diseases.
“This makes telomeres important markers of biological age, or how worn down our cells are,” said Scott Ogletree, corresponding author of a paper on the study and a former postdoctoral researcher at North Carolina State University’s Center for Geospatial Analytics. “And we know that many variables – such as stress – can influence how quickly our telomeres wear down.”
Preventing the shortening of telomeres is therefore key to a long healthy life. Now, new research is indicating that green spaces can indeed achieve this.
The CDC’s National Health and Nutrition Examination Survey (NHANES) for the years 1999-2002 served as the study’s data source. Through interviews and physical tests, the NHANES longitudinal, nationally representative study evaluates the health of the American population.
The researchers specifically examined information on 7,827 individuals that allowed them to evaluate their demographics, the length of their telomeres, and where they lived. The study team evaluated each person’s neighborhood’s green space and how that connected to their telomere length.
“We found that the more greenspace people had in their neighborhoods, the longer their telomeres were,” said Aaron Hipp, co-author of the study and a professor of parks, recreation and tourism management at NC State. “That was true regardless of race, economic status, whether they were drinkers or smokers, etc.”
Benefits virtually vanished
The effects of green space were, however, limited and virtually vanished when the researchers took into account other aspects of each neighborhood, such as air pollution, segregation, or “deprivation.” In other words, even while telomere length appears to be protected by green space, the harm caused by other causes seems to outweigh that protection.
“Green space 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,” added Hipp. “This study drives home the idea that creating green space 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.”
There is a lot of interest in potential therapies to protect or prolong telomeres as a means of promoting lifespan and health. Research into telomeres and their function in aging and disease is still ongoing. This study provides one approach to prolonging telomeres but others need to be included to outweigh the negative effects on telomeres caused by societal issues.
The study is published in the journal Science of the Total Environment.
The exposome, reflecting the range of environmental exposures individuals encounter throughout their life, can influence a variety of health outcomes and can play a role in how the environment impacts our genes. Telomeres, genetic structures regulating cell growth and senescence, are one pathway through which the exposome may impact health. Greenspace exposure, representing the amount of green areas in one’s neighborhood, is one component of the exposome and has been associated with multiple health benefits. To investigate the potential link between greenspace exposure and telomere length, we analyzed data from the 1999–2001 National Health and Nutrition Examination Survey (NHANES) sample. Our study examined individual, risk, and contextual factors. We found that greater greenspace exposure in one’s neighborhood was associated with longer telomere lengths when considering individual and risk factors, suggesting a positive effect of living in greener neighborhoods. However, this relationship became non-significant when contextual factors, such as air pollution and deprivation, were included in the analysis. These findings highlight a complex relationship between greenspace and telomere length, warranting further research to explore contextual factors in detail.