Delaying Retirement May Help Lower Dementia Risk, Study Finds — Updated Insights

Is working a few more years good for your brain? According to a study of over 429,000 workers, the answer is yes. Each extra year of working past typical retirement age cut dementia risk by around 3.2% (HR 0.968) — even when excluding those who developed dementia within five years of retiring. The findings add to growing evidence that staying mentally and socially active, through work or other meaningful engagement, can help protect against Alzheimer’s and other forms of cognitive decline. It turns out that retirement might come with more than financial tradeoffs — it could also impact your long-term brain health.

More than just a number, this supports the “use-it-or-lose-it” concept: mental engagement at work helps maintain cognitive reserve, keeping the mind sharper longer. That reserve comes from complex thinking, social interaction, and purpose — factors that build up resilience against Alzheimer’s .

As Americans increasingly delay retirement, a French study indicates this scenario may have a silver lining: a lower risk of developing Alzheimer’s disease.

Researchers analyzing health and insurance records of more than 429,000 self-employed workers found a 3 percent reduction in dementia risk for each extra year at the age of retirement. Workers evaluated had been retired for an average of more than 12 years, and 2.65 percent of the group had dementia.

“There’s increasing evidence that lifestyle factors such as exercise, mental activities, social engagement, positive outlook and a heart-healthy diet may reduce the risk of developing Alzheimer’s disease and other forms of dementia,” said Dr. James Galvin. “Now we can add staying in the workforce to this list of potential protective factors.”

Galvin, director of the Pearl Barlow Center for Memory Evaluation and Treatment at the NYU Langone School of Medicine, was not involved with the research.

The study, led by Carole Dufouil, director of research in neuroepidemiology at the French National Institute of Health and Medical Research, is scheduled to be presented at an Alzheimer’s Association conference in Boston. Research presented at scientific conferences typically has not been peer-reviewed or published and results are considered preliminary.

About 5.2 million Americans have been diagnosed with Alzheimer’s disease, which is the sixth leading cause of death in the United States, according to the Alzheimer’s Association.

Americans are increasingly putting off retirement, especially those in the middle class. According to a 2012 Wells Fargo survey of 1,000 Americans earning less than $100,000 annually, almost one-third said they’d need to work until age 80 to live comfortably in retirement.

But Dufouil’s research, which linked health and pension databases of self-employed workers who were retired as of 2010, puts a positive spin on that choice. In study background materials, she said the data is in line with the “use it or lose it” hypothesis of brain health. The study showed an association between higher retirement age and lower dementia risk, but not a cause-and-effect relationship.

One Alzheimer’s disease expert was not surprised by the findings.

“There seems to be growing evidence that staying cognitively [mentally] active is really important to reducing a person’s risk, and perhaps professional activity may be one of those cognitive activities,” said Heather Snyder, director of medical and scientific operations for the Alzheimer’s Association, based in Chicago. “What we know is that things that promote lifelong learning seem to be beneficial. But that may mean different things for different people…and exactly what that is, we can’t define at this point in time.”

For his part, Galvin noted several caveats to keep in mind when interpreting the study’s meaning. First, he said, self-employed workers may be inherently different than company-employed workers, with differences in skill sets, work environment, stress and social mobility that might affect the study’s results.

Also, the prevalence of dementia was based on a review of either an existing dementia diagnosis or prescription for dementia-related medication, he noted.

“There is no way of knowing about those individuals who did not seek medical attention, did not have access to health care or who were not properly diagnosed,” Galvin added. “Nonetheless, the study supports the concept that keeping oneself mentally, physically and socially active over the span of a lifetime may have important effects on both physical and mental health.”

New Data Since Headline Findings

1. Social activity delays dementia diagnosis by ~5 years
A 2025 study from Rush University followed 1,923 older adults and found that those most socially active were diagnosed about five years later compared to the least active — and had a 38% lower risk of dementia.

2. Physical activity protects the brain
USC researchers tracked nearly 50,000 adults and reported that individuals who sat for 15 hours a day had over three times the dementia risk compared to those with healthier activity levels. Staying physically active actively supports brain resilience.

3. Midlife exercise preserves brain structure
A Brain Communications study found lifelong physical activity before age 50 helps maintain memory-related brain regions. Active adults showed better brain volume and cognitive function, even when they carried Alzheimer’s markers.

4. Greenspace exposure slows cognitive decline
A Boston University study revealed that midlife exposure to residential greenery slows cognitive decline by nearly eight months annually — especially in lower-SES neighborhoods and among APOE‑ε4 carriers.

5. Mentally demanding work builds cognitive reserve
Multiple international studies, including one of 108,000 participants, confirm that jobs with high mental demands (creativity, learning, control) delay dementia compared to repetitive or low-demand roles.

Why This Matters

Age-specific dementia rates are declining
A Lancet analysis shows that while absolute dementia numbers rise with aging populations, the age-specific rates have dropped by about two-thirds in the US, UK, France, Sweden, and the Netherlands over the past four decades — largely due to reduced smoking, better education, and improved vascular health.

Delaying onset delivers major impact
If Alzheimer’s onset were delayed by five years, the number of Americans aged 70+ with Alzheimer’s in 2050 would drop from 9.1 million to just 5.4 million — cutting prevalence by over 40%.

What You Can Do

Here’s how to build protective habits:

• Stay mentally engaged: Keep working, learning, socializing.
• Move daily: Walk, lift weights, reduce sedentary time.
• Eat and live well: Mediterranean-style diet, manage blood pressure and weight.
• Stay social: Regular interaction delays dementia by years.
• Embrace nature: Greenspace exposure boosts brain health.

Bottom Line

Pushing retirement later isn’t about working longer — it’s about keeping your brain working. Combining big-picture lifestyle strategies with day-to-day mental, physical, and social activity builds a stronger defense against dementia. That’s the real takeaway from recent research.

More Information

The Alzheimer’s Association has more about living with Alzheimer’s.