Alzheimer’s: The 12 Modifiable Risk Factors According to the WHO

title: Alzheimer’s’s prevention: 12 modifiable risk factors WHO reduce dementia 40%

description: Complete guide 12 modifiable risk factors Alzheimer’s’s according WHO Lancet: prevent 40% dementia cases, act on education, hearing, smoking, depression, social isolation, hypertension, obesity, diabetes, alcohol, head trauma, air pollution, physical inactivity and reduce disease risks.

keywords: Alzheimer’s’s, prevention, risk factors, WHO, Lancet, dementia, modifiable, reduce risk, health

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Alzheimer’s’s, prevention, risk factors, WHO, Lancet, dementia, modifiable, health, risk reduction, lifestyle

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Reading time: 36 minutes

“Alzheimer’s’s is a genetic lottery, nothing can be done.” “If it’s in my genes, I’ll get it anyway.” “Prevention doesn’t really work.” “Too late for me, I’m 60.”

FALSE. Alzheimer’s’s ≠ Inevitable genetic fate. Science reveals: 40% of dementia cases could be prevented or delayed by acting on 12 modifiable risk factors. That’s huge. The Lancet Commission (2020, updated 2024), validated by WHO, identifies these factors: Limited education, hearing loss, smoking, depression, social isolation, hypertension, obesity, diabetes, excessive alcohol, head trauma, air pollution, physical inactivity. Some act young (education), others midlife (hypertension), others elderly (isolation). Each factor = Power to act. Modifying lifestyle, today, reduces Alzheimer’s’s risk, tomorrow.

This guide details the 12 factors, explains mechanisms, and provides concrete actions for each.

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Table of Contents

1. Alzheimer’s’s Prevention: The Scientific Revolution

2. The 12 Modifiable Risk Factors

3. Limited Education (youth)

4. Hearing Loss (midlife)

5. Smoking (midlife)

6. Depression (midlife, elderly)

7. Social Isolation (elderly)

8. Hypertension (midlife)

9. Obesity (midlife)

10. Diabetes (midlife)

11. Excessive Alcohol Consumption (midlife)

12. Head Trauma (lifelong)

13. Air Pollution (lifelong)

14. Physical Inactivity (lifelong)

15. Taking Action: Where to Start?

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Alzheimer’s’s Prevention: The Scientific Revolution {#revolution-scientifique}

Lancet Commission 2020-2024

Global Reference:

Lancet: Prestigious medical journal (reference).

Commission: 28 international experts (neuroscience, epidemiology, public health).

Publication: 2020 (updated 2024).

Conclusion:

40% of dementia cases: Preventable/delayable (action on modifiable factors).

Remaining 60%: Genetics, age, uncontrollable factors (but 40% = Immense).

Why This Is Revolutionary

Before:

Fatalism: “Alzheimer’s’s = Lottery, nothing to do.”

Focus: Medications (repeated failures).

Now:

Hope: Prevention possible (individual, collective power).

Actions: Concrete, accessible (lifestyle).

Public Health: Prevention campaigns (governments, WHO).

Mechanism

Risk Factors:

Brain Damage: Inflammation, oxidative stress, vascular damage.

Cognitive Reserve: Reduced (compensation capacity).

Accumulation: Cumulative effects (multiple factors = Risk +++).

Prevention:

Reduces Damage: Brain protected.

Increases Reserve: Plasticity, connections (disease compensation).

Delays Symptoms: Even with amyloid plaques (brain resists more).

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The 12 Modifiable Risk Factors {#12-facteurs}

Overview

By Life Period:

Youth (<45 years):

1. Limited education

Midlife (45-65 years):

2. Hearing loss

3. Smoking

4. Depression

5. Hypertension

6. Obesity

7. Diabetes

8. Excessive alcohol consumption

Later Life (>65 years):

9. Social isolation

10. Depression (also)

Lifelong:

11. Head trauma

12. Air pollution

13. Physical inactivity (implicit in Commission, added from studies)

Relative Contribution

Estimates (% attributable risk):

Limited education: 7%

Hearing loss: 8%

Hypertension: 2%

Obesity: 1%

Smoking: 5%

Depression: 4%

Physical inactivity: 3%

Diabetes: 3%

Social isolation: 4%

Alcohol: 1%

Head trauma: 3%

Air pollution: 2%

Total: ~40% (rounded).

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Limited Education (youth) {#education}

Impact

Education:

Cognitive Reserve: Building (childhood, adolescence, young adults).

Neuronal Connections: Learning creates (density, plasticity).

Limited Education:

Less than 12 years schooling: Increased risk (vs higher education).

Brain: Less reserve (limited Alzheimer’s’s compensation).

Mechanism

Early Intellectual Stimulation:

Neurons: Connection multiplication (synapses).

Plasticity: Flexible, adaptable brain.

Adult: Reserve = Buffer (compensated damage).

Actions

For Yourself:

If limited education: Compensate (continuing education, reading, lifelong learning).

Never too late: Cognitive stimulation (adult, senior) effective.

For Children, Grandchildren:

Encourage studies: Maximum possible (not pressure, but support).

Reading: From young age.

Cognitive activities: Educational games, music, languages.

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Hearing Loss (midlife) {#audition}

Impact

Hearing Loss:

Midlife: 45-65 years (often ignored, minimized).

Alzheimer’s’s Risk: +8% (major factor).

Mechanism

Reduced Hearing:

Isolation: Difficult conversations (social withdrawal).

Cognitive Load: Brain compensates (fatigue, diverted resources).

Reduced Stimulation: Sensory inputs (under-stimulated brain).

Atrophy: Brain auditory zones (degenerate if not stimulated).

Actions

Screening:

Regular: Audiogram (50 years, then every 2-3 years).

Signs: Asking to repeat, loud TV, group difficulty.

Hearing Aids:

Hearing Aids: As soon as loss detected (don’t wait).

Reimbursement: Social security, insurance (recent improvement).

Early Correction:

Effective: Before established isolation (preserves cognition).

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Smoking (midlife) {#tabac}

Impact

Smoking:

Alzheimer’s’s Risk: +5% (also stroke, cancer, cardiovascular disease).

Dose-dependent: More smoking, more risk.

Mechanism

Toxins:

Vascular Damage: Brain arteries (micro-strokes, ischemia).

Inflammation: Chronic (brain).

Oxidative Stress: Free radicals (damaged neurons).

Amyloid Accumulation: Promoted (Alzheimer’s’s plaques).

Actions

Quit:

Never too late: Even at 60, benefits (brain partially recovers).

Aids: Nicotine substitutes, medications (Champix), tobacco specialists.

Number: 39 89 (Tobacco Information Service).

Avoid passive smoking:

Exposure: Also harmful (protect yourself).

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Depression (midlife, elderly) {#depression}

Impact

Depression:

Midlife: +4% Alzheimer’s’s risk.

Elderly: Factor also (but sometimes early Alzheimer’s’s symptom, complex).

Mechanism

Chronic Depression:

Hippocampus: Atrophy (memory area).

Inflammation: Cerebral (pro-inflammatory cytokines).

Cortisol: Elevated (stress hormone, toxic to neurons).

Withdrawal: Social, activities (under-stimulation).

Actions

Treat Depression:

Consult: Doctor, psychiatrist, psychologist.

Therapies: CBT (cognitive-behavioral therapies), antidepressants (if necessary).

Don’t trivialize: “It’s age, it’ll pass” (no, treat).

Prevention:

Physical activity: Natural antidepressant (endorphins).

Social: Maintain connections (support).

Sleep: Regular (7-8h).

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Social Isolation (elderly) {#isolement}

Impact

Isolation:

Elderly: +4% Alzheimer’s’s risk.

Vicious Circle: Isolation → Cognitive decline → More isolation.

Mechanism

Social Interactions:

Cognitive Stimulation: Conversations, exchanges (engage memory, language, attention).

Positive Emotions: Connections (protective).

Isolation:

Under-stimulation: Brain (atrophy).

Depression: Frequent (risk factor also).

Sedentary: Often associated (physical inactivity).

Actions

Maintain Connections:

Family, Friends: Calls, visits (regular).

Associations: Senior clubs, volunteering, cultural activities.

New Encounters: Classes, workshops (never “too old”).

Technology:

Video: Video calls (distant family).

Social Networks: Adapted for seniors (stay connected).

Animals:

Companionship: Dog, cat (indirect social connection, walks, routine).

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Hypertension (midlife) {#hypertension}

Impact

Hypertension:

Midlife: 45-65 years (+2% Alzheimer’s’s risk).

Elderly: Link less clear (paradox, too low pressure also risk).

Mechanism

Elevated Blood Pressure:

Vascular Damage: Brain (micro-strokes, leukoaraiosis).

Blood-Brain Barrier: Permeability (toxins enter brain).

Hypoperfusion: Brain areas (oxygen lack).

Vascular Dementia: Direct, but also Alzheimer’s’s (mixed lesions).

Actions

Control Pressure:

Regular Measurement: Home, doctor.

Target: <140/90 mmHg (midlife), adjust according to age.

Treatments:

Medications: Antihypertensives (if prescribed, take).

Lifestyle:

• Reduce salt (home cooking, avoid prepared meals).
• Exercise (30 min/day).
• Healthy weight.
• No smoking, moderate alcohol.

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Obesity (midlife) {#obesite}

Impact

Obesity:

Midlife: BMI ≥30 (+1% Alzheimer’s’s risk).

Interactions: With diabetes, hypertension (cumulative risk).

Mechanism

Excess Fat:

Inflammation: Chronic (pro-inflammatory adipokines).

Insulin Resistance: Brain (disturbed glucose metabolism).

Vascular Damage: Atherosclerosis (micro-strokes).

Hormones: Imbalances (disturb neurons).

Actions

Lose Weight:

Goal: BMI <30 (ideal 20-25).

Method:

• Balanced diet (see MIND diet later).
• Regular exercise (cardio + Strength).
• Medical follow-up (dietitian, doctor).

No drastic diets: Yo-yo (ineffective long term).

Prevention:

Young: Maintain healthy weight (avoid obesity setting in).

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Diabetes (midlife) {#diabete}

Impact

Type 2 Diabetes:

Midlife: +3% Alzheimer’s’s risk.

Also: Vascular dementia.

Mechanism

Hyperglycemia:

Vascular Damage: Micro-angiopathy (brain).

Glycation: Proteins (damaged neurons).

Cerebral Insulin Resistance: Glucose enters poorly (reduced neuron energy).

Inflammation: Chronic.

Alzheimer’s’s = “Type 3 Diabetes”: Hypothesis (brain insulin resistance).

Actions

Prevent Diabetes:

Diet: Low glycemic index, fiber.

Exercise: Regular (insulin sensitivity).

Weight: Maintain health.

If Diabetes:

Control Blood Sugar: HbA1c <7% (target).

Treatments: Antidiabetics (take correctly).

Follow-up: Medical (vascular complications).

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Excessive Alcohol Consumption (midlife) {#alcool}

Impact

Alcohol:

Excessive: >21 drinks/week (+1% Alzheimer’s’s risk).

Moderate: Debate (some say protective, others neutral).

Excessive: Direct brain toxicity.

Mechanism

Excessive Alcohol:

Neurotoxic: Direct (destroys neurons).

B1 Deficiency: Thiamine (Wernicke-Korsakoff syndrome, dementia).

Vascular Damage: Stroke, brain atrophy.

Inflammation: Chronic.

Actions

Limit:

Recommendations: Max 10 drinks/week, 2 drinks/day, alcohol-free days.

Ideal: Less (or zero).

If Dependence:

Help: Addiction specialists, AA (Alcoholics Anonymous).

Withdrawal: Medical (dangerous alone if severe dependence).

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Head Trauma (lifelong) {#traumatismes}

Impact

Trauma:

Repeated mild: Concussions (contact sports, falls).

Severe: Accidents (car, serious fall).

Alzheimer’s’s Risk: +3% (cumulative).

Mechanism

Impact:

Axonal Damage: Neuron connections (damaged).

Inflammation: Acute then chronic (if repeated).

Tau Accumulation: Protein (tangles, Alzheimer’s’s).

CTE: Chronic traumatic encephalopathy (boxers, American footballers, early dementia).

Actions

Prevent:

Sports: Helmets (cycling, skiing), protections (contact sports).

Car: Seatbelt, careful driving.

Home: Prevent falls (seniors: stairs, rugs).

If Trauma:

Rest: Cognitive (limited screens, reading).

Consultation: Doctor (monitoring).

Don’t minimize: “Simple bump” (if symptoms: headaches, dizziness, confusion).

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Air Pollution (lifelong) {#pollution}

Impact

Pollution:

Fine Particles: PM2.5, PM10 (vehicles, industries).

Alzheimer’s’s Risk: +2% (chronic exposure).

Mechanism

Particles:

Inhaled: Lungs, then blood (cross blood-brain barrier).

Inflammation: Brain (activated microglia).

Oxidative Stress: Free radicals.

Amyloid Accumulation: Promoted.

Actions

Reduce Exposure:

Avoid: Pollution peaks (stay indoors, alert days).

Transportation: Less car (walking, cycling quiet routes, public transit).

Home: Ventilate (early morning, late evening, avoid rush hours).

Air Purifiers: If highly polluted area (HEPA filters).

Plants: Indoor (absorb pollutants, modest).

Policy:

Support: Anti-pollution measures (vote, petitions).

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Physical Inactivity (lifelong) {#inactivite}

Impact

Sedentary:

Alzheimer’s’s Risk: +3% (varying estimates).

Multifactorial: Links obesity, diabetes, hypertension (factors).

Mechanism

Physical Exercise:

Blood Circulation: Brain (oxygen, nutrients).

BDNF: Neurotrophic factor (neuron growth, plasticity).

Neurogenesis: Hippocampus (new neurons, even adults).

Inflammation: Reduced.

Inactivity:

Reverse: All benefits lost.

Actions

Move:

Recommendation: 150 min/week (moderate) or 75 min (intense).

Types:

• Brisk walking (30 min/day).
• Swimming, cycling, dancing.
• Gardening, active housework.
• Strength training (2 times/week).

Lifelong:

Children: Daily activity (habits).

Adults: Maintain (stairs vs elevator).

Seniors: Adapt (gentle gym, water aerobics).

See dedicated article: Alzheimer’s’s and exercise (later).

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Taking Action: Where to Start? {#agir}

Assess Personal Risks

List of 12 Factors:

Check: Those that concern you.

Prioritize: Easily modifiable factors (quick wins).

Progressive Action Plan

Not all at once:

Failure: Drastic changes (unsustainable).

Method: 1-2 factors / 3 months (anchor habits).

Examples:

Quarter 1: Quit smoking + Walk 30 min/day.

Quarter 2: Control pressure + Reduce alcohol.

Quarter 3: Lose 5 kg + Join social club.

Medical Follow-up

Assessment:

45 years: Hypertension, diabetes, cholesterol, BMI.

50 years: Audiogram.

60 years: Cognitive evaluation (baseline).

Regular: Primary care physician (adjust).

Combine Factors

Synergy:

Exercise: Reduces obesity, diabetes, hypertension, depression, isolation.

Diet: Controls weight, diabetes, hypertension.

Social: Fights isolation, depression.

Act on multiple fronts: Maximizes benefits.

Never Too Late

Even at 70:

Benefits: Exercise, social, diet (proven).

Decline: Slowed (improved quality of life).

Hope: Every change counts.

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Testimonials

John, 58 years old

“45 years: Hypertension detected, ignored. 50 years: Overweight (BMI 32), smoker. Mother Alzheimer’s’s 72 years, fear. Read Lancet Commission. Decision: Act. Quit smoking (difficult, 6 months patches). Exercise: Cycling 3 times/week. Diet: Less salt, more vegetables. 3 years later: BMI 26, normal pressure, fit. Fear Alzheimer’s’s? Still. But I act. Control.”

Mary, 65 years old

“Retirement: Isolation (friends gone, husband deceased). Latent depression. Daughter pushes to consult: Psychologist, antidepressants 6 months. Join book club, library volunteering. Now: Rich social life, better morale. Daughter says: “Mom transformed.” Alzheimer’s’s prevention? Didn’t think initially. Now understand: Act today = Protection tomorrow.”

Paul, 72 years old

“Believed too late (72 years). Son shows studies: “Never too late Dad.” Started daily walking (30 min), stopped excessive TV, cognitive activities (SCARLETT, crosswords). 2 years later: Stable memory (cognitive tests), energy, optimism. Regretted not doing before, but proud now.”

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Conclusion: 40% of Power in Your Hands

Alzheimer’s’s ≠ Inevitable fate. 40% preventable/delayable cases = Revolution. 12 modifiable risk factors = 12 action levers. Education, hearing, smoking, depression, isolation, hypertension, obesity, diabetes, alcohol, trauma, pollution, inactivity: Each = Power. Act young (education, trauma prevention), midlife (hypertension, smoking, hearing), elderly (isolation, exercise): Lifelong = Opportunities. Lifestyle changes = Not guarantee (genetics, age remain), but maximize chances healthy brain. Start today. One factor. Then two. Then three. Your brain will thank you. Tomorrow, 10 years, 30 years. Alzheimer’s’s prevention = Marathon, not sprint. But every step counts.

The 12 factors to remember:

1. ✅ Education (maximize youth, compensate adult)

2. ✅ Hearing (screen, use hearing aids)

3. ✅ Smoking (quit)

4. ✅ Depression (treat)

5. ✅ Isolation (social connections)

6. ✅ Hypertension (control)

7. ✅ Obesity (lose weight)

8. ✅ Diabetes (prevent, control)

9. ✅ Alcohol (limit)

10. ✅ Trauma (prevent)

11. ✅ Pollution (reduce exposure)

12. ✅ Inactivity (move)

You are not alone. Our Alzheimer’s’s training explains prevention. SCARLETT stimulates cognition (cognitive reserve). Free guide: All resources.

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DYNSEO resources for prevention:

• Alzheimer’s’s Training: Understanding risk factors and prevention
• SCARLETT: Daily cognitive stimulation (reserve)
• Free guide for supporting people with Alzheimer’s’s

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You read list 12 factors. Check mentally: Smoking (yes), sedentary (yes), isolation (starting). Fear rises. Then, realize: Power. Each factor = Lever. You decide: Quit smoking (now), walk 30 min daily (tomorrow), call lost friend (tonight). Small steps. But directed. Toward protected brain, long life, lucid. 40% in your hands. You clench fists. Act. Today.