Dementia is not an inevitable part of aging. Although we cannot change our genes or prevent time from passing, we can take powerful steps to protect our brains — and reduce the risk of dementia. Research shows that a substantial proportion of dementia cases worldwide may be preventable. In fact, modifying a specific group of 14 lifestyle and environmental factors could prevent or delay up to 45% of dementia cases.

Why Modifiable Risk Factors Matter

These risk factors are called “modifiable” because they are, to some extent, within our control. While it may not be easy to change long-standing habits or overcome environmental barriers, doing so can have significant health benefits — not only for brain function but also for heart disease, diabetes, stroke, and other chronic illnesses. The earlier we start, the better the results.

Changes can be made at all stages of life. Even people in later life can benefit from adjustments to their daily routines, medical care, and social engagement.

The 14 Modifiable Risk Factors for Dementia

1. Physical Inactivity

A sedentary lifestyle is one of the leading risk factors for dementia. Regular physical activity boosts blood flow to the brain, supports cardiovascular health, reduces inflammation, and improves mood and sleep — all of which are linked to better cognitive function.

• Aim for at least 150 minutes of moderate aerobic activity (like brisk walking or cycling) or 75 minutes of vigorous activity (like jogging or swimming) per week.
• Even light activities like gardening, dancing, or walking the dog count.

2. Smoking

Smoking causes oxidative stress and inflammation, damages blood vessels, and increases the risk of stroke and other vascular conditions — all contributing to brain damage and cognitive decline. Smokers are at a significantly higher risk of developing dementia.

• Quitting smoking reduces risk at any age.
• Seek help through smoking cessation programs, nicotine replacement therapy, or medication.

3. Excessive Alcohol Consumption

Heavy and regular drinking is associated with brain atrophy, memory loss, and increased dementia risk. Alcohol also raises the risk of depression, liver disease, and falls.

• Drink moderately
• Avoid binge drinking and seek support if alcohol misuse is a concern.

4. Air Pollution

Long-term exposure to fine particulate air pollution has been linked to accelerated cognitive decline and increased dementia risk. Polluted environments can harm brain function over time.

• Reduce exposure by using air purifiers, avoiding outdoor activity during peak pollution times, and supporting policies that promote clean energy and urban greenery.

5. Head Injury

Traumatic brain injury, even when mild or moderate, can increase dementia risk — especially if sustained during midlife. Causes include road accidents, falls, and high-impact sports.

• Wear helmets when biking or motorcycling.
• Reduce fall hazards at home, especially for older adults.
• Advocate for safer sports practices and protective regulations.

6. Infrequent Social Contact

Loneliness and social isolation have been shown to increase the risk of dementia. Social interaction stimulates cognitive processes, enhances mood, and supports healthy behaviors.

• Stay connected with friends, family, or community groups.
• Join clubs, volunteer, or attend classes or religious services.
• Even brief social interactions have mental health benefits.

7. Lower Educational Attainment

Education helps build “cognitive reserve” — the brain’s resilience to age-related decline. People with limited education in childhood and early adulthood are at higher risk of developing dementia later in life.

• Support and invest in universal access to quality early-life education.
• Promote adult learning, cognitive stimulation, and skill-building activities at all ages.

8. Obesity (Especially in Midlife)

Obesity increases inflammation, insulin resistance, and vascular damage — all risk factors for dementia. The link is strongest when obesity occurs during midlife (ages 45–65).

• Aim for a healthy body weight through balanced nutrition and regular activity.
• Focus on whole foods, reduce processed sugar and fat, and practice portion control.

9. Hypertension

High blood pressure — particularly during midlife — can damage blood vessels in the brain, leading to vascular dementia or contributing to Alzheimer's disease.

• Monitor blood pressure regularly.
• Follow a DASH or Mediterranean-style diet, reduce salt intake, and take medication if prescribed.

10. Type 2 Diabetes

Diabetes damages small blood vessels and increases inflammation, both of which affect the brain. People with diabetes are at greater risk of developing cognitive impairment and dementia.

• Manage blood sugar through diet, physical activity, and medication.
• Screen regularly for early signs of complications.

11. Depression

Depression is both a risk factor and an early symptom of dementia. Chronic depression may affect brain structure, reduce motivation, and interfere with healthy behaviors.

• Seek professional mental health support.
• Engage in therapy, medication, social activities, and stress-reduction techniques.

12. Hearing Loss

Untreated hearing loss is associated with increased cognitive decline, social withdrawal, and loneliness — all of which impact brain health. Hearing aids can reduce this risk.

• Get your hearing checked, especially after age 50.
• Use hearing aids or assistive devices when needed.

13. Vision Impairment

Visual problems, such as cataracts or diabetic retinopathy, may increase dementia risk if left untreated. However, some conditions like glaucoma and macular degeneration do not appear to increase the risk.

• Have regular eye exams.
• Treat conditions like cataracts early; surgery can restore vision and may help reduce dementia risk.

14. High LDL Cholesterol

Elevated low-density lipoprotein (LDL) cholesterol levels contribute to atherosclerosis, stroke risk, and inflammation. They may also accelerate brain changes linked to Alzheimer’s.

• Adopt a heart-healthy diet rich in fiber, fruits, vegetables, and lean proteins.
• Consider medication if recommended by your doctor.

Dementia does not have to be an inevitable outcome of aging.

Let’s take the first step — for ourselves, our loved ones, and the generations to come.