Top Alzheimer’s Risk Factors (Ranked)

1. Age (by far the strongest)

Risk rises sharply after 65, doubling approximately every 5 years.

2. Genetics – especially the APOE-ε4 gene

Having one APOE-ε4 copy increases risk; two copies increase it significantly more.
Family history also increases risk.

3. Cardiovascular and metabolic health

Anything that damages blood vessels or metabolic function raises Alzheimer’s risk:

  • High blood pressure

  • Diabetes

  • High cholesterol

  • Obesity (midlife)

  • Heart disease

  • Stroke / mini-strokes

4. Lower education / lifelong cognitive inactivity

Lower cognitive reserve is associated with earlier or more rapid decline.

5. Traumatic brain injury (TBI)

Moderate or severe head injury increases risk; repeated concussions increase it further.

6. Lifestyle factors

  • Smoking

  • Physical inactivity

  • Poor diet (high sugar, ultra-processed foods)

  • Excessive alcohol

  • Lack of social engagement

7. Chronic inflammation

Long-term systemic inflammation, autoimmune issues, and untreated infections may contribute.

8. Sleep disorders

Chronic sleep deprivation and untreated sleep apnea are linked to increased amyloid buildup.

9. Environmental exposures

Long-term exposure to air pollution, toxins, and heavy metals (where significant) can increase risk.