Parks as public health infrastructure: research links green space to lower suicide rates

When we think about preventing suicide, we usually picture clinical solutions: screenings in doctors' offices, therapy sessions, medications, or crisis hotlines. We rarely think about the neighborhood park down the street. But a recent study suggests that the built environment surrounding us — specifically, whether our community has accessible green space — may play a surprisingly powerful role in shaping suicide risk.

Researchers found that urban U.S. counties with at least one publicly accessible park had a 19% lower suicide rate than urban counties with no parks, even after accounting for demographic factors and social vulnerability. The protective association was even stronger among adults over the age of 65. Yet when the researchers ran the same analysis in England and Wales, where parks are nearly universal, the effect largely disappeared. The findings suggest that green space matters for mental health, but its impact depends heavily on the broader social and environmental context in which it exists. This nuance could reshape how we view the connections between urban planning and public health.

Untangling statistical factors

Previous research linking green space to lower suicide rates struggled to rule out the possibility that wealthier, less disadvantaged communities were simply better resourced across the board, with parks being just one visible marker of overarching disparity.

“Initially, the idea behind our study was essentially to debunk the association between green space and suicide rates — to explain all of it by social vulnerability,” said senior author Robert Gibbons, PhD, director of the Center for Health Statistics and Professor of Medicine and Public Health Sciences at the University of Chicago. “The surprising truth of the matter is that while social vulnerability does moderate the association to some degree, the link stands as significant on its own."

Gibbons and first author Shuhan Liu, a doctoral student in statistics at Northwestern University and a previous UChicago statistics master’s student of Professor Gibbons, were uniquely positioned to test the question rigorously. Gibbons previously collaborated with other UChicago researchers to develop the Social Vulnerability Metric (SVM), a model-based estimator that captures neighborhood-level disadvantage across dimensions including income, education, healthcare access, and infrastructure to produce a single score strongly correlated with health outcomes. The SVM has outperformed other measurements of social determinants of health, such as the CDC’s Social Vulnerability Index (SVI), in accurately predicting health outcomes like overall mortality and emergency room visits.

Using suicide data from the U.S. Centers for Disease Control (CDC) spanning 2019–2023, the team analyzed all urban counties in the United States, then replicated their analysis across all urban local authorities in England and Wales. They examined four different measures of green space: the total number of parks in a region, the proportion of land area covered by parks, how close residents lived to a park, and the average size of parks.

The work required some statistical creativity. The CDC suppresses suicide counts for counties with nine or fewer deaths to protect privacy, meaning small counties appear as blanks in the data. “We don't know if it's zero suicides or nine suicides,” Gibbons said. To handle that, he and Liu used a censored negative binomial model — a technique borrowed in part from environmental statistics, where pollutant concentrations often fall below detection limits.

Having parks makes a big difference; having more parks may not

The most striking finding was in the U.S. data: even after adjusting for social vulnerability, demographic composition, and other confounding factors, the presence of at least one open park in an urban county was associated with a 19% reduction in suicide rate compared to urban counties with no parks. Among older adults, the association was even more pronounced.

In England and Wales, however, the same pattern did not emerge. Every urban local authority studied had at least 14 parks or gardens, whereas roughly 6% of U.S. counties had none at all. “Where parks are essentially universal, like England and Wales, the sheer number of parks tells you nothing about the quality of those parks and their accessibility,” Gibbons said. “Counting parks alone doesn't tell you whether people have access to safe and usable restorative green space.” The present study provides a methodological paradigm that urban planning researchers can use to dig into questions of park quality and access in the future.

The researchers also found that bigger parks weren't necessarily better. In the U.S., larger average park size was actually associated with slightly higher suicide rates. Gibbons said this is likely because oversized parks tend to be in more rural areas, and rurality is itself a risk factor for suicide.

A new lens for suicide prevention

Gibbons is careful to note that the study is observational and ecological, meaning it identifies associations between community-level features and suicide rates rather than proving that parks themselves directly reduce individual risk. Still, he believes the findings should broaden the conversation about prevention.

“When we think about suicide prevention, we usually think about it in terms of individuals — screening, diagnoses, treatment,” he said. “Our study suggests that the environment in which people live also matters. Suicide is a complex outcome, and its prevention may require thinking not only about healthcare but also about the structure of communities.”

For urban planners, that could mean treating parks not just as amenities that improve quality of life, but as public health infrastructure — particularly in the 71 urban U.S. counties currently without a single open park.

“I don't think there are psychological therapies that will produce a 19% reduction in death by suicide,” Gibbons said. “This is an observational study, and there may be other confounding variables. But we've picked up on and adjusted for some pretty big ones, yet still found a substantive result.”

“Greenspace and suicide rate: comparing and contrasting the U.S., England & Wales” was published in Landscape & Urban Planning in August 2026. Authors are Shuhan Liu and Robert Gibbons.