Top Five Dementia Risk Factors To Look Out For

By Melissa Fleur Afshar

Life and Trends Reporter

ShareNewsweek is a Trust Project member

Over 55 million people live with dementia globally, a number projected to nearly triple come the year 2050. A significant portion of these cases, however, may be preventable.

According to neuroscientists, geriatric psychiatrists and dementia researchers, nearly half of all dementia cases could be avoided or delayed by addressing a handful of modifiable risk factors early and consistently throughout life.

Experts who spoke with Newsweek emphasized that while some risk factors—like genetics—may be beyond control, a growing body of evidence points to lifestyle and environmental factors that can be acted upon now to protect the brain as it ages.

Neuroscientist Lila Landowski told Newsweek that “seven percent of dementia is linked to hearing loss, seven percent to high LDL blood pressure, five percent to less education and five percent to social isolation.”

She added that “equal fifth” risk contributors—at three percent each—include depression, traumatic brain injury and air pollution.

...

Vascular Health

Uncontrolled vascular risk is one of the most important—and most underappreciated—factors influencing dementia onset.

“Midlife hypertension, diabetes, high cholesterol and smoking significantly increase dementia risk,” Dr. Barbara Sparacino, an adult and geriatric psychiatrist known as The Aging Parent Coach, told Newsweek. “I often tell patients: ‘What protects your heart usually protects your brain.’”

That link is backed by recent global data. A 2024 study published by The Lancet Commission confirmed that midlife high cholesterol and hypertension rank among the most consequential contributors to dementia onset.

The report estimated that addressing 14 modifiable risk factors—including vascular conditions—could prevent or delay 45 percent of dementia cases worldwide.

Sparacino urged people not to dismiss “borderline” numbers on routine health tests, emphasizing that “treating blood pressure, blood sugar, and cholesterol...may be one of the most powerful long-term ways to lower dementia risk.”

Hearing Loss

Once viewed as a quality-of-life issue, untreated hearing loss is now recognized as a powerful and preventable dementia risk factor.

“When you can’t hear well, your brain works overtime just to decode sound,” Sparacino said. “People often withdraw socially. That combination of increased cognitive load plus isolation is hard on the brain over time.”

Landowski agrees. She said that hearing loss makes it harder for a person to socialize, do activities and maintain their independence, and as a result in some cases, their cognitive function.

Treating hearing loss early—through hearing aids, cochlear implants or assistive devices—can have measurable effects.

Social Disconnection

Loneliness, isolation and lack of cognitive engagement can erode brain health over time.

“The brain is a social, learning organ,” Sparacino said. “You don’t need fancy brain games—just regular conversation, reading, volunteering, classes, communities and hobbies all count as meaningful cognitive exercise.”

Depression and Chronic Stress

Mental health is not just emotional—it is structural, too, and long-standing depression and chronic stress can physically alter the brain.

“In older adults, persistent depression can both mimic dementia and increase vulnerability to it,” Sparacino said.

She encourages families to treat mood disorders as essential medical conditions rather than ancillary concerns.

“Treating mood and stress [is] a key part of protecting brain health," she explained.

Stress elevates cortisol, an essential hormone that when in overdrive for chronic periods can do harm. Chronic elevated cortisol levels are associated with inflammation and impaired cognition.

Dr. Aaron Ritter, director of the Memory and Cognitive Disorders Program at Hoag’s Pickup Family Neurosciences Institute, told Newsweek that untreated mood disorders can contribute to “brain inefficiencies” and raise dementia risk over time.

Physical Inactivity

Perhaps the most consistently overlooked variable is movement.

“Movement supports blood flow, reduces vascular risk, and helps preserve brain volume and function,” Sparacino said. “We’re not aiming for marathon training—just consistent, doable movement.

"That also reduces falls, which can dramatically worsen cognition."

Sparacino recommends walking, light cardio, strength, and balance exercises most days of the week.

Dr. Amy Sanders—a neurologist with Sunday Health—described physical inactivity, especially when coupled with a poor diet or essential vitamin deficiencies, as a primary threat to cognitive function.

"Regularly engaging in aerobic exercise and strength training is one of the most effective ways to reduce the risk of dementia," Sanders told Newsweek. "It improves cardiovascular health, blood flow to the brain, and can reduce inflammation."

She added: "A diet high in saturated fats, sugars, refined carbohydrates, and ultra-processed foods is also associated with a higher risk of cognitive decline and Alzheimer's disease."

Is there a health issue that's worrying you? Let us know via [email protected]. We can ask experts for advice, and your story could be featured on Newsweek.

Reference

Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission—The Lancet. (2024). Retrieved December 3, 2025, from https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(24)01296-0/abstract

Request Reprint & LicensingSubmit CorrectionView Editorial & AI Guidelines