The phrase “food swamp” was created more than a decade ago to describe regions where fast-food franchises and convenience shops dominate, flooding the neighborhoods with bad eating alternatives as opposed to healthier ones. Food swamps are often associated with food deserts, where a lack of grocery shops makes it difficult to get fresh produce and nutritional food.
“Despite major advances in stroke care, stroke continues to be a significant problem, and some people will remain at risk despite optimal medical treatment,” adds lead author Dixon Yang. “An unhealthy diet negatively impacts blood pressure, blood glucose and cholesterol levels that increases the risk of stroke. 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.”
Food swamps and the possible relation to stroke have not been well investigated. In this study, researchers looked at whether food swamp settings were linked to an increased risk of stroke. They examined data from the Health and Retirement Study (HRS), an ongoing investigation of aging and retirement run by the University of Michigan that enrolls people from around the country. The U.S. Department of Agriculture’s food environment data was then cross-referenced with this information to create the retail food environment index (RFEI), which measures the proportion of fast-food outlets and convenience stores to the availability of retail healthy food options in a given neighborhood.
This research was a secondary examination of data obtained between 2010 and 2016. Based on participant health data, researchers then applied an enhanced retail food environment score. The retail food environment index classed grocery shops, farmer’s markets, and specialty food stores as healthy food retailers whereas convenience stores, fast food chains, and full-service restaurants were categorized as unhealthy food alternatives.
The research comprised 17,875 people (average age 64 years; 54% women; 84% white adults) who were statistically weighted to approximate the broader U.S. population. Each individual was weighted based on survey design/sampling to ensure that the group was representative of a considerably broader U.S. population of more than 84 million stroke-free community-dwelling people. The retail food environment index was divided into two categories: ratios of less than 5 and ratios of 5 or higher.
“The two categories were chosen for comparison because prior research has shown that a retail food environment index ratio of 5 or higher may predict the prevalence of people with obesity in a neighborhood,” Yang adds.
Over 3 million persons, or 3.8% of those surveyed, self-reported having had a stroke.
The research revealed:
72% of individuals reside in places with a food environment index score of 5 or above, compared to 28% of residents in regions with a retail food environment index below 5.
When compared to residents in neighborhoods with an index score below 5, those in the higher retail food environment index group (ratio 5 or more) had 13% greater risks of experiencing a stroke event.
According to Yang, the median retail food environment index for all towns was 6, which meant that 6 times as many unhealthy food retailers were present as healthy food retailers.
“Our research highlights the potential importance of an area’s retail food options as a structural factor affecting stroke, especially since most participants resided in areas with 6 times the amount of relative unhealthy to healthy food choices,” Yang says.
Researchers were unable to verify cause and effect between retail food environment index and stroke due to the study’s cross-sectional design, which covered just a single period of time. Additionally, there was no information on the kind of stroke, and strokes were self-reported.
“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, especially among people who may have difficulty in reaching optimal cardiovascular health targets. In the future,” Yang adds, “it may help to focus on community-based interventions or dietary guidance to improve cardiovascular health, thereby, hopefully reducing the risk of stroke.”
According to Anne N. Thorndike, M.D., M.P.H., FAHA, the director of the Cardiac Lifestyle Program at Massachusetts General Hospital, the majority of the respondents in this research of older, community-dwelling adults in the United States resided in locations with a high density of unhealthy food alternatives.
“The association between having a stroke and living in an unhealthy food environment,” comments the expert who was not involved in the study, “highlights the importance of having effective policies and programs that can help to improve access to healthier food options for all Americans.”
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