Food insecurity linked to higher dementia risk, especially before 65, study finds

Food insecurity is linked to a higher risk of cognitive impairment and dementia, with the strongest effect among people under 65, according to a multi-country study of aging Americans. The research, conducted by teams from Harvard University, the University of Michigan, Queen’s University Belfast and Johns Hopkins Bloomberg School of Public Health, analyzed data from the Health and Retirement Study to track cognitive outcomes over roughly nine years.

The study followed 5,851 adults aged 50 and older, with an average age of 67, who did not have dementia or cognitive impairment at the outset. Participants were assessed for cognitive health every two years, and researchers adjusted for wealth, education and pre-existing health conditions to isolate the impact of hunger on brain aging.

At the start, about 9% of participants experienced low food security and 7% had very low food security, while more than 83% were food secure. Food security status was measured using a six-item module that categorizes access to enough food and anxiety about food supply. Cognitive health outcomes ranged from normal aging to mild impairment and dementia.

Across the follow-up period, those with low or very low food security were about 1.6 to 1.8 times more likely to develop neurological conditions, including mild cognitive impairment or dementia, than their food-secure peers. Importantly, the association varied by age. The link between food insecurity and cognitive problems was significantly stronger for adults under 65, where the risk more than doubled. For adults over 65, the relationship was weaker and often not statistically significant.

The researchers emphasized that the age pattern suggests a crucial window for intervention. Strikingly, stronger associations among those younger than 65 imply that addressing food insecurity between ages 50 and 65 could yield the greatest cognitive benefit later in life. As the team wrote, "Stronger associations among older adults younger than 65 years suggest that this subgroup may gain greater cognitive benefits from interventions targeting food insecurity."

Experts have long noted that food insecurity can trigger a cascade of health harms beyond hunger. When people cannot access nutritious food, diets often become poorer, increasing risks for heart disease, diabetes and obesity, while the stress of ongoing hunger can heighten anxiety and depress mood. Over time, limited nutrition and chronic stress can contribute to cognitive decline and, in some cases, dementia.

The authors advocate for policy actions to reduce hunger and improve nutrition for older Americans. They highlighted measures such as expanding nutrition assistance programs for seniors, increasing access to meals served in group settings at senior centers or community locations, and strengthening the Supplemental Nutrition Assistance Program (SNAP).

"Our findings suggest that policies addressing food insecurity may reduce the risk of cognitive impairment among aging adults," the researchers concluded.

Food insecurity remains a nationwide challenge, affecting an estimated 47 million Americans at some point each year. The new study adds to a growing body of evidence that hunger and poor nutrition are not only immediate concerns but may also shape cognitive health decades into the future.

Health officials say the implications are clear: expanding access to reliable, nutritious food for midlife and older adults could help slow the trajectory of dementia and support brain health across the aging population. While the data cannot prove causation, the association observed across nearly a decade of follow-up highlights a potentially modifiable risk factor for cognitive decline.

In the near term, health systems and policymakers may consider targeted nutrition support in midlife as part of a broader dementia prevention strategy, embracing programs that ensure stable meal access, monitoring of nutritional status and coordination with social services to reduce food insecurity before cognitive symptoms emerge.