(The Hill) — Adults ages 50 and older who live near fast food-dense environments may be at heightened risk of stroke, preliminary research has determined. 

So-called “food swamps” typically contain an abundance of fast-food chains and convenience stores — essentially “swamping” neighborhoods with unhealthy eating options, the authors explained. 

Meanwhile, food swamps also often overlap with food deserts, where insufficient grocery stores complicate the quest to find fresh produce, they added.

“An unhealthy diet negatively impacts blood pressure, blood glucose and cholesterol levels that increases the risk of stroke,” lead author Dixon Yang, a postdoctoral fellow at Columbia University Irving Medical Center, said in a statement

“Independent of one’s own demographics or socioeconomic status, living in a neighborhood with an abundance of poor food choices may be an important factor to consider for many people,” Yang added. 

To determine the connection between food swamp density and stroke risk, the researchers performed a secondary analysis of data collected from 2010 to 2016 on 17,875 adults. 

The initial data came from the University of Michigan’s ongoing Health and Retirement Study, which recruits participants across the U.S. to explore the challenges and opportunities associated with aging. 

The researchers then cross-referenced this information with food environment details from the U.S. Department of Agriculture, to create a so-called “retail food environment index.”

The index, they explained, indicates the ratio of unhealthy food options to the number of healthy choices in each neighborhood. 

Unhealthy food options included convenience stores, fast-food and full-service restaurants, while healthy food retailers included grocery stores, farmer’s markets and specialized food stores, according to the report.

The areas with more unhealthy choices generally had a ratio of higher than five, while those with healthier options had a ratio of five or lower.

“Prior research has shown that a retail food environment index ratio of five or higher may predict the prevalence of people with obesity in a neighborhood,” Yang said.

Yang and his colleagues then weighted the 17,875 adults to be representative of a much larger U.S. population of more than 84 million community-dwelling adults. 

More than 3 million people — or 3.8 percent of those studied — self-reported having experienced a stroke, the scientists found.

About 28 percent of those surveyed lived in areas with a retail food environment index below five — the areas with healthier options. 

The remaining 72 percent lived in regions ranked five or higher on the index, according to the research. 

Those who lived in the neighborhoods with less healthy options had 13 percent greater odds of stroke in comparison to residents of areas that ranked below five, the authors found.  

The scientists acknowledged several limits in their research, including the single time period evaluated and the fact that stroke events were self-reported. 

In addition, the research is still in preliminary stages — to be presented at next week’s American Stroke Association conference — and has yet to be peer-reviewed. 

“At this early stage of our research, it’s important to raise awareness that a person’s neighborhood and food environment are potentially important factors affecting their health,” Yang said. 

“In the future, it may help to focus on community-based interventions or dietary guidance to improve cardiovascular health, thereby, hopefully reducing the risk of stroke,” he added.