Older adults who experienced food insecurity later in life had higher odds of probable dementia.
The association was strongest among people who experienced food insecurity during both midlife and later life.
Researchers say the findings show a connection, but they don't prove that food insecurity causes dementia.
Not always knowing whether you'll have enough food for yourself or your household can take a toll in many ways. Now, new research suggests that food insecurity later in life may also be connected with cognitive health.
A University of Michigan study published in The American Journal of Clinical Nutrition looked at whether food insecurity at different points in adulthood was associated with probable dementia later on. The researchers were particularly interested in whether the timing of food insecurity made a difference.
Researchers followed adults for more than 20 years
The study included 2,051 adults who were part of the Panel Study of Income Dynamics, a nationally representative U.S. household survey that has followed families for decades.
Researchers examined food insecurity during two periods: 1999 to 2003, when participants were in midlife, and 2015 to 2019, when they were in later life. Food insecurity was measured using an established 18-question survey that assesses experiences related to having inadequate resources to obtain food.
“Not only can we now track the changes one family experiences, but by collecting this information for decades, we can also examine different parts of the life course,” researcher Noura Insolera said in a news release.
“We have known for some time that hunger and nutritional deficiencies make it harder for children to learn in school, for example, but only by collecting this information year after year for many years can we look at something like the connections between food insecurity and dementia risk.”
The researchers then assessed probable dementia in 2019 and 2021 using an eight-question screening tool called the AD8. A score of two or higher was considered probable dementia.
The analysis accounted for factors including age, sex, race and ethnicity, education, marital status, employment, homeownership, family income, and several health conditions.
The timing of food insecurity appeared to matter
After accounting for these factors, adults who experienced food insecurity only in later life had 1.85 times the odds of probable dementia compared with adults who remained food secure during both periods. Those who experienced food insecurity during both midlife and later life had 2.18 times the odds.
By comparison, food insecurity during midlife alone was not significantly associated with probable dementia.
The researchers also found that adults who experienced food insecurity during both periods had an estimated 40% probability of probable dementia, compared with 11% among those who remained food secure. Those who experienced food insecurity only during later life had an estimated 34% probability.
Still, these results don't establish cause and effect. The study was observational, meaning it identified an association rather than proving that food insecurity itself leads to dementia. The researchers noted that other factors connected with food insecurity could help explain the relationship.
“The physical toll that a lack of nutrition has on the body is a tangible health issue, but the mental strain of worry and anxiety about where their next meal might come from is also a very real problem,” Insolera said. “Food insecurity causes both of these, and the combination of these adverse physical and mental conditions can create a problem that is larger than the sum of its parts.”