Surprising Dementia Data Suggest Being Unmarried May Lower Risk

An 18-year U.S. study challenges the belief that marriage protects against cognitive decline

Topline:

Contrary to common belief, new research shows that older adults who were never married, divorced, or widowed had a lower risk of developing dementia than those who were married—challenging long-held assumptions about the protective effects of marriage on brain health.

Authors Opinion
This study challenges earlier research suggesting that marriage protects against cognitive decline. It raises an important question: have societal dynamics shifted in ways that now alter the impact of marriage on brain health—or is there a missing piece in our understanding that these findings haven't yet captured?

Study Details

This new insight into dementia risk and marital status comes from a large-scale U.S. study published in Alzheimer’s & Dementia and conducted using data from the National Alzheimer’s Coordinating Center (NACC). The study followed over 24,000 older adults for 18 years, providing one of the most comprehensive looks at how relationship status might influence cognitive decline.

Earlier studies, including data from the Health and Retirement Study (2000–2014), suggested the opposite—that unmarried people had higher odds of dementia. This newer analysis paints a different picture.

Methodology

Participants aged 60+ were recruited from Alzheimer’s Disease Research Centers across the U.S. and underwent yearly assessments that included clinical evaluations and neuropsychological testing. At baseline, none of the 24,107 participants had dementia. They were categorized by marital status: married, never married, divorced (including separated), and widowed.

Over a median of nearly 4 years, researchers tracked dementia diagnoses, including Alzheimer's disease, Lewy body dementia, vascular dementia, and frontotemporal dementia.

Key Findings

• Never married adults had the lowest risk of dementia (HR 0.60).

• Divorced individuals showed a similarly reduced risk (HR 0.66).

• Widowed participants also fared better than married individuals, though the risk reduction was slightly less pronounced (HR 0.73).

• These associations remained significant even after adjusting for demographics and baseline cognitive status.

• Unmarried individuals also had a lower risk of progressing from mild cognitive impairment to dementia.

Researchers hypothesize that married individuals may face stressors such as caregiving burdens, smaller social networks, or reliance on partners, which could influence brain health.

Implications for Practice

For Patients:

• Being unmarried does not increase your dementia risk—in fact, it may offer unexpected cognitive resilience.

• Maintaining independence and diverse social connections could be more protective than marital status alone.

For Healthcare Providers:

• Reconsider blanket assumptions that marriage inherently benefits cognitive aging.

• Evaluate patients' social structures and stress levels, not just relationship status, when assessing dementia risk.

• Encourage all older adults—married or unmarried—to build robust support systems and practice self-care.