Food Security As a Brain Protector? Study Links SNAP to Lower Dementia Risk

Older adults who struggle with food insecurity experience worse brain health, including faster rates of cognitive decline and increased risk of developing dementia. 

But, in the United States, the Supplemental Nutrition Assistance Program (SNAP) — which reduces food insecurity by providing funds for people with low income to buy groceries — has been linked to better health outcomes for eligible people at all ages, from childhood to later life. And according to data from a large national survey, that translates to healthier cognitive aging, too.

As the U.S. Congress greenlights nearly $300 billion in federal funding cuts to the food security program over the coming decade, researchers from the University of Georgia presented evidence indicating that SNAP participation protects against food insecurity-linked cognitive decline.

“By improving access to nutrient-rich foods, SNAP can help support brain health, reduce stress, and promote better overall health,” Linlin Da, a health services researcher at UGA who led the study, told Being Patient. Her team, which presented the study results at this week’s Alzheimer’s Association International Conference in Toronto, pointed to evidence suggesting that the benefits of food assistance are long-lasting — and that investing in SNAP now can pay dividends as participants age, especially in reduced dementia care costs.

Evidence for SNAP’s protective health benefits

Da and her team analyzed responses to the University of Michigan’s Health and Retirement Study, a nationally representative sample of adults over the age of 50. The researchers identified 1,131 respondents who were enrolled in the program in 2010, and 1,216 who were not enrolled, even though their low income made them eligible. Then, Da’s team tracked changes in each participant’s cognitive function — as indicated by their responses to the survey — over the following decade.

It turned out that SNAP participants had a slightly slower rate of year-over-year cognitive decline, suggesting that increased access to food can help people with low income maintain brain health as they age. While participation in the program only reduced the annual change by 0.l percent, Da said that that seemingly small difference can add up over time, delaying the onset of cognitive impairment and dementia. 

“It allows older adults to maintain independence longer,” she said.

Variable results from past studies

Da and her team were not the first group to study the effect of SNAP participation on cognitive health. Overall, the results of such studies have historically been mixed: Researchers who examined data from the National Health and Aging Trends Study also found that SNAP participation protected against food insecurity-linked cognitive decline. But another group found that SNAP participation had no effect on dementia risk for older adults who participated in the Panel Study of Income Dynamics (PSID). 

While the variability of these results could reflect differences in the surveys — each of which includes a different set of questions, and samples a slightly different segment of the American public — it could also indicate limitations in the capacity of SNAP to fully address food insecurity. Outside of the COVID pandemic, during which Congress temporarily increased benefits, the available data show that many SNAP participants still struggle with food insecurity.

“Most people spend all of their benefits in the second or third week [of the month],” Cindy Leung, a public health researcher at Harvard University who led the study analyzing data from the PSID, told Being Patient. That leaves those people vulnerable to the negative health effects that come with inconsistent access to food.

Leung added that other factors may prevent participants from fully realizing the cognitive health potential benefits of assistance programs like SNAP as well. She said that a person’s diet depends on their ability to access grocery stores and to prepare their own food, regardless of whether they can afford the food. If a person lives in a food desert or has no way to operate a kitchen, then funding from SNAP cannot necessarily grant them food security or the health benefits.

Da may have found evidence of these other factors in her study. She and her team compared the rates of cognitive decline among white, Black, and Hispanic SNAP participants. Although all three groups benefited from the program, non-Hispanic white participants showed the slowest rate of cognitive decline. Da said that this difference could reflect structural barriers that prevent older adults of color from consistently obtaining nutritious food. 

Food insecurity and public health

The results of Da’s study suggest that some changes to the country’s existing food assistance programs may be necessary to ensure that all participants receive the same brain health benefits. However, Leung explained that studying the connection between SNAP participation and health becomes even more difficult when researchers and policymakers look beyond simple associations, and try to identify targetable improvements to achieve specific public health goals. 

For instance, when and how food insecurity influences dementia risk is not clear. Food insecurity can lead to a host of mental and physical health issues — all of which, like increased stress and risk of cardiovascular disease, are linked to dementia — and those issues can affect a person as long as they struggle to find adequate food. 

“We’ve seen every health behavior that you can think of as negatively associated with food insecurity: poor diet, lower physical activity, poor sleep, more smoking, more alcohol use,” Leung said. Without a more precise understanding of how SNAP participation may protect against cognitive decline and when it may be most crucial, it can be difficult to identify effective changes to the program that would help more participants age better.

Still, the question for Leung is not whether ameliorating food insecurity could improve health (including cognitive health) but whether assistance programs like SNAP provide adequate support to help participants live healthier lives. 

Any answer to that question will have to account for the changes in SNAP included in the One Big Beautiful Bill Act, which shifts some of the program’s costs to states and increases the age cutoff for work requirements to 65.

Regardless, Da said that her study offers evidence that public investment in food security programs can help older adults to maintain cognitive health later in life. 

“Cognitive aging is not only about some genetics problems — it can also be shaped by policies, by our environment, by access to different resources like food,” she said. “Everyday support programs can make a real difference.” 

Andrew Saintsing (@AndrewSaintsing) earned a PhD in biology, and now he writes about science for outlets like Drug Discovery News.