The study, published in the journal Circulation, found some surprising connections between urban nature and heart health.

Researchers found that living in an urban environment with access to nature can decrease your chances of developing coronary artery calcification (CAC). CAC occurs when calcium builds up as plaque in the walls of your heart’s coronary arteries. It is an early sign of heart disease and can also cause heart attack.

This trend was more noticeable among Black individuals and those living in neighborhoods with lower socioeconomic status.

The study showed that Black participants with the highest accessibility to rivers had 32% lower odds of CAC compared to those with the lowest accessibility. Black participants with greater access to green spaces had up to 35% lower odds of CAC.

“The protective effect of having access to urban blue and green spaces with coronary artery calcification highlighted in our study underscore the potential benefits of green and blue spaces, particularly for underserved populations at higher risk for cardiovascular disease,” says corresponding author Lifang Hou, MD, PhD, chief of Cancer Epidemiology and Prevention in the Department of Preventive Medicine at Northwestern University Feinberg School of Medicine.  

How Do Green and Blue Spaces Improve Health?

According to Dr. Hou, exposure to green and blue spaces can boost your immune system, reduce chronic inflammation and slow down the biological aging process.

But that’s not all. These natural areas offer:

• More opportunities for physical activity
• Spaces for social interaction
• A natural stress reliever

All of these factors contribute to better metabolic and cardiovascular health.

How the Study Was Conducted

The study followed 2,960 Black and white men and women* from four major U.S. cities — Birmingham, Chicago, Minneapolis and Oakland — over a 25-year period (1985-1986 to 2010-2011). The average age of participants was 50 years old.

While previous research has linked proximity to urban blue and green spaces with better cardiovascular health, this study broke new ground. It specifically examined the role of social determinants of health, such as race and neighborhood socioeconomic status, using long-term observational data.

Researchers assessed participants’ access to nature by measuring:

• Percent of blue space cover
• Distance to the nearest river
• Percent of green space cover
• Distance to the nearest major park

All of these factors were considered within a five-kilometer radius of participants’ homes.

At around age 50, participants underwent CT scans to check for CAC. Researchers then examined the relationships between each type of natural space and CAC, taking into account both race and neighborhood socioeconomic status.

Other Factors Impacting Access to Green and Blue Spaces

While the benefits are clear, accessing these spaces isn’t always easy for everyone.

“The poor condition of parks and/or safety concerns in underserved urban neighborhoods might stop residents from using parks and prevent them from fully benefitting from these spaces,” says study first author Kyeezu Kim, PhD, assistant professor of Preventive Medicine at Northwestern University Feinberg School of Medicine. “From a public health perspective, it’s important to look at the social determinants of health of participants as well. More data is warranted to fully explain this observation.”

What This Means for You

This study was just the beginning. “More studies are needed to fully understand the role of urban natural environments in pathways related to human health,” adds Dr. Hou.

But from what this study has shown, it’s important for your heart to get outside and enjoy green and blue spaces near you whenever possible.  Even if you live in the heart of the city, finding ways to incorporate nature into your routine can make a difference. You could:

• Seek out local parks for regular visits
• Make a nearby lake or river (if you have one) a destination for walks
• Take your lunch breaks outdoors in a green space near your workplace
• Plan weekend nature walks
• Incorporate indoor plants into your home or office décor
• Attend outdoor fitness classes held in parks

Making any of these a regular part of your routine can have positive effects on your well-being.

Learn about CAC.

*Scientists do not always collect information from participants about gender identity. To avoid misrepresenting the results of this research, we use the same terminology as the study authors.