YapSpan

Your Alzheimer’s risk

Alzheimer’s is the most common dementia, genes load the dice but do not throw them, and sleep is when the brain clears the protein at the center of it.

Updated 2026-08-17

Test yourself: Sleep quiz10 questions · ~2 minStart →

Alzheimer’s risk, by the numbers

🧩
15–20 yrs

before the first symptom is when Alzheimer’s pathology starts accumulating, which makes your 40s and 50s the decade that counts.

Risk multipliers and protectors

Associations with Alzheimer’s and dementia

APOE4, two copies8–12×
APOE4, one copy≈3×
First-degree family history≈2×
MIND diet, strict adherence−53%
Midlife sleep of 6 h or less+30%
Anti-amyloid drugs, early stage−27–35% decline
works in your favor works against you

[1] · [2] · [3] · [4]

The 8 things to know about Alzheimer’s risk

?%

What raises dementia risk most

50%25%0%25%50%75%100%← more risk · % change in risk · less risk →Factors, ranked by biggest effect1349%#1120%#2≈76%#312%60%#470%#570%#626%≈35%#760%#850%#949%#1044%#1140%#1240%#1330%#1430%#1530%#1626%#17≈4%20%#1823%#1923%#2023%#2122%#2220%#2320%#2420%#2519%#2610%#27Everythingelseno single number

Scroll sideways to see every factor →

Tap a pill to answer yours.

Where you sit

0 of 27 answered

Answer the 27 factors above to see which ones raise your own risk, which sit at the reference, and which the studies have no number for.

Relative risk versus each factor’s reference group; above the line is lower risk, below it higher.

Sources (28)Livingston G, Huntley J, Liu KY, et al., Lancet 2024 · Zhong et al., PLoS One 2015 · Yeo BSY, Song HJJMD, Toh EMS, et al., JAMA Neurol 2023 and 25 moreShow all
  1. [1]E. Genin et al. APOE and Alzheimer disease: a major gene with semi-dominant inheritance. Mol Psychiatry, 16(9):903-7, 2011. doi:10.1038/mp.2011.52 Evidence: Low
  2. [2]G. Livingston et al. Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission. Lancet, 404(10452):572-628, 2024. doi:10.1016/S0140-6736(24)01296-0 Evidence: Not graded (review)
  3. [3]S. A. Shumaker et al. Conjugated equine estrogens and incidence of probable dementia and mild cognitive impairment in postmenopausal women: Women's Health Initiative Memory Study. JAMA, 291(24):2947-58, 2004. doi:10.1001/jama.291.24.2947 Evidence: Moderate
  4. [4]S. A. Shumaker et al. Estrogen plus progestin and the incidence of dementia and mild cognitive impairment in postmenopausal women: the Women's Health Initiative Memory Study: a randomized controlled trial. JAMA, 289(20):2651-62, 2003. doi:10.1001/jama.289.20.2651 Evidence: Moderate
  5. [5]Y. Vinogradova et al. Use of menopausal hormone therapy and risk of dementia: nested case-control studies using QResearch and CPRD databases. BMJ, 374:n2182, 2021. doi:10.1136/bmj.n2182 Evidence: Low
  6. [6]N. Pourhadi et al. Menopausal hormone therapy and dementia: nationwide, nested case-control study. BMJ, 381:e072770, 2023. doi:10.1136/bmj-2022-072770 Evidence: Low
  7. [7]A. Sommerlad et al. Association of social contact with dementia and cognition: 28-year follow-up of the Whitehall II cohort study. PLoS Med, 16(8):e1002862, 2019. doi:10.1371/journal.pmed.1002862 Evidence: Low
  8. [8]D. A. R. Sutin et al. Sense of meaning and purpose in life and risk of incident dementia: New data and meta-analysis. Arch Gerontol Geriatr, 105:104847, 2023. doi:10.1016/j.archger.2022.104847 Evidence: High
  9. [9]C. A. C. Coupland et al. Anticholinergic Drug Exposure and the Risk of Dementia: A Nested Case-Control Study. JAMA Intern Med, 179(8):1084-1093, 2019. doi:10.1001/jamainternmed.2019.0677 Evidence: Low
  10. [10]K. H. Franks et al. Association of Stress with Risk of Dementia and Mild Cognitive Impairment: A Systematic Review and Meta-Analysis. J Alzheimers Dis, 82(4):1573-1590, 2021. doi:10.3233/JAD-210094 Evidence: Low
  11. [11]L. Johansson et al. Midlife psychological stress and risk of dementia: a 35-year longitudinal population study. Brain, 133(Pt 8):2217-24, 2010. doi:10.1093/brain/awq116 Evidence: Low
  12. [12]B. S. Y. Yeo et al. Association of Hearing Aids and Cochlear Implants With Cognitive Decline and Dementia: A Systematic Review and Meta-analysis. JAMA Neurol, 80(2):134-141, 2023. doi:10.1001/jamaneurol.2022.4427 Evidence: High
  13. [13]M. Zuin et al. Risk of dementia in patients with atrial fibrillation: Short versus long follow-up. A systematic review and meta-analysis. Int J Geriatr Psychiatry, 36(10):1488-1500, 2021. doi:10.1002/gps.5582 Evidence: Moderate
  14. [14]G. Zhong et al. Smoking Is Associated with an Increased Risk of Dementia: A Meta-Analysis of Prospective Cohort Studies with Investigation of Potential Effect Modifiers. PLoS One, 10(3):e0118333, 2015. doi:10.1371/journal.pone.0118333 Evidence: High
  15. [15]Y. Leng et al. Association of Sleep-Disordered Breathing With Cognitive Function and Risk of Cognitive Impairment: A Systematic Review and Meta-analysis. JAMA Neurol, 74(10):1237-1245, 2017. doi:10.1001/jamaneurol.2017.2180 Evidence: Moderate
  16. [16]P. Iso-Markku et al. Physical activity as a protective factor for dementia and Alzheimer's disease: systematic review, meta-analysis and quality assessment of cohort and case-control studies. Br J Sports Med, 56(12):701-709, 2022. doi:10.1136/bjsports-2021-104981 Evidence: High
  17. [17]O. M. Shannon et al. Mediterranean diet adherence is associated with lower dementia risk, independent of genetic predisposition: findings from the UK Biobank prospective cohort study. BMC Med, 21(1):81, 2023. doi:10.1186/s12916-023-02772-3 Evidence: Low
  18. [18]S. Su et al. Leisure Activities and the Risk of Dementia. Neurology, 99(15), 2022. doi:10.1212/WNL.0000000000200929 Evidence: High
  19. [19]X. Qi et al. Dose-Response Meta-Analysis on Tooth Loss With the Risk of Cognitive Impairment and Dementia. J Am Med Dir Assoc, 22(10):2039-2045, 2021. doi:10.1016/j.jamda.2021.05.009 Evidence: Moderate
  20. [20]S. Asher et al. Periodontal health, cognitive decline, and dementia: A systematic review and meta-analysis of longitudinal studies. J Am Geriatr Soc, 70(9):2695-2709, 2022. doi:10.1111/jgs.17978 Evidence: Low
  21. [21]S. Sabia et al. Association of sleep duration in middle and old age with incidence of dementia. Nat Commun, 12(1):2289, 2021. doi:10.1038/s41467-021-22354-2 Evidence: Low
  22. [22]D. Hughes et al. Association of Blood Pressure Lowering With Incident Dementia or Cognitive Impairment: A Systematic Review and Meta-analysis. JAMA, 323(19):1934-1944, 2020. doi:10.1001/jama.2020.4249 Evidence: High
  23. [23]M. Eyting et al. A natural experiment on the effect of herpes zoster vaccination on dementia. Nature, 641(8062):438-446, 2025. doi:10.1038/s41586-025-08800-x Evidence: Low
  24. [24]M. Pomirchy et al. Herpes Zoster Vaccination and Dementia Occurrence. JAMA, 333(23):2083-2092, 2025. doi:10.1001/jama.2025.5013 Evidence: Low
  25. [25]M. Taquet et al. The recombinant shingles vaccine is associated with lower risk of dementia. Nat Med, 30(10):2777-2781, 2024. doi:10.1038/s41591-024-03201-5 Evidence: Low
  26. [26]L. Shi et al. Sleep disturbances increase the risk of dementia: A systematic review and meta-analysis. Sleep Med Rev, 40:4-16, 2018. doi:10.1016/j.smrv.2017.06.010 Evidence: Moderate
  27. [27]O. M. Bubu et al. Sleep, Cognitive impairment, and Alzheimer's disease: A Systematic Review and Meta-Analysis. Sleep, 40(1), 2017. doi:10.1093/sleep/zsw032 Evidence: High
  28. [28]M. Melville et al. Menopause hormone therapy and risk of mild cognitive impairment or dementia: a systematic review and meta-analysis. Lancet Healthy Longev, 6(12):100803, 2025. doi:10.1016/j.lanhl.2025.100803 Evidence: Low
Open What Matters →

Learn more about all the dementia factors, with the factor-by-factor walkthrough on its own page.

The short version

  • •Alzheimer’s disease causes roughly two thirds of dementia. It is defined by two proteins, amyloid plaques and tau tangles, that begin accumulating 15 to 20 years before the first symptom, which is why prevention is a midlife project.
  • •Genes matter but are not destiny: one copy of the APOE4 variant roughly triples risk and two copies raise it around 8 to 12 fold, yet many carriers never develop the disease, and lifestyle factors still move risk in carriers.
  • •Sleep is the brain’s rinse cycle: the glymphatic system clears amyloid mainly during deep sleep, a single night of deprivation measurably raises brain amyloid on PET scans, and people sleeping 6 hours or less in midlife had about 30% higher dementia incidence in a 25-year cohort.
  • •The MIND diet, a Mediterranean pattern tuned for the brain with berries and leafy greens, was associated with 53% lower Alzheimer’s incidence in strict adherers in the original cohort study.
  • •The field has changed: blood tests can now detect Alzheimer’s pathology, and the first anti-amyloid drugs slow early-stage decline by about 27 to 35%, which makes catching it early worth far more than it used to be.
Test yourself: Sleep quiz10 questions · ~2 minStart →

Alzheimer’s deserves its own look beyond general dementia risk, because it has its own biology: a slow, silent accumulation of amyloid and tau that starts in midlife, a major susceptibility gene that a quarter of people carry, and a uniquely strong link to how you sleep. It is also where the science is moving fastest, with blood tests and the first disease-slowing drugs arriving. None of this is cause for fatalism; it is cause for specifics. Here is what the evidence actually says, and what to do about it.

1

The 20-year head start

Amyloid plaques and tau tangles begin accumulating 15 to 20 years before symptoms (Bateman et al. [5], dominantly inherited cohort). The disease you would be diagnosed with at 75 is largely built in your 50s and 60s, which is when prevention has the most leverage.

Do this

Treat your 40s and 50s as the decade that counts. Every item below works best started before anything feels wrong.

2

Know what APOE4 does and does not mean

About 1 in 4 people carry one copy of APOE4, which roughly triples Alzheimer’s risk; two copies (about 2%) raise it around 8 to 12 fold [1]. But risk is not fate: many carriers never develop the disease, and exercise, sleep, and vascular health measurably modify risk in carriers.

Do this

If you test your genes, do it with your eyes open: the result changes urgency, not strategy. Everything on this list applies harder, not differently, to carriers.

Take the family history quiz →
3

Sleep, the amyloid rinse cycle

The glymphatic system flushes amyloid from the brain primarily during deep sleep. One night of total deprivation raised hippocampal amyloid on PET scans [6], and people sleeping 6 hours or less at 50 and 60 had about 30% higher dementia incidence over 25 years [2].

Do this

Protect a 7 to 8 hour sleep opportunity like a prescription, and treat loud snoring or apnea: fragmented sleep skips the deep stages where the clearing happens.

Take the sleep quiz →
4

Exercise, the best drug we have today

Active people develop Alzheimer’s meaningfully less often, and trials show aerobic exercise increases hippocampal volume in older adults [7], directly countering the atrophy pattern of early disease. Benefits appear in APOE4 carriers too.

Do this

The hippocampus responds to the sweaty kind: 3 or 4 sessions a week that raise your heart rate, sustained for months. Think of it as volume training for your memory hub.

Take the exercise quiz →
5

Eat for your brain: the MIND pattern

The MIND diet, Mediterranean plus DASH with specific weight on leafy greens and berries, was associated with 53% lower Alzheimer’s incidence in the highest adherers, and 35% lower even in moderate adherers [3]. A later randomized trial was shorter and showed smaller differences, so treat the exact number gently and the direction seriously.

Do this

The two signature moves are cheap: leafy greens most days, berries a few times a week, olive oil as the default fat.

Take the diet quiz →
6

Family history sharpens, not seals, the odds

A first-degree relative with Alzheimer’s roughly doubles your risk through shared genes and habits. The practical value of knowing is timing: earlier attention to sleep, vascular health, and hearing, and earlier baseline cognitive checks.

Do this

If a parent or sibling had it, tell your doctor now, not at first symptom, and put the modifiable list on a schedule. Family history is a reason to act early, never a verdict.

Take the family history quiz →
7

The heart-brain axis, again

Midlife hypertension, diabetes, smoking, and obesity all raise Alzheimer’s risk specifically, not just vascular dementia; mixed pathology is the rule in autopsy studies. Amyloid plus damaged small vessels produces symptoms sooner than either alone.

Do this

Your blood pressure cuff and HbA1c test are Alzheimer’s tools. Keeping vessels healthy raises the amount of pathology your brain can tolerate silently.

Take the heart health quiz →
8

Early detection finally pays

Blood biomarkers (like p-tau217) can now flag Alzheimer’s pathology with high accuracy, and anti-amyloid antibodies slowed decline by about 27% (lecanemab) [4] to 35% (donanemab) [8] in early-stage disease. Modest, real, and only useful if caught early.

Do this

Take persistent memory change seriously, in yourself or family, and push past "just aging" dismissals. An early, accurate answer now has treatment consequences.

Take the preventive care quiz →

How to tell if yours is good

Signals you can read yourself, starting today, and what a good reading looks like.

Sleep

7 to 8 hours most nights, without loud snoring or gasping

Fitness

3+ heart-rate-raising sessions a week

Plate

Leafy greens most days, berries weekly, olive oil as the default

Vascular numbers

Blood pressure and HbA1c checked and in range

Family awareness

You know your family history and your doctor knows it too

Memory

No persistent change that friends or family have started noticing

Check your own risk

6 quick questions about you, not the article. You get a personal readout of where your risks sit.

Pick an answer to reveal the numbers: check points for every answer (+2p working for you, +1p worth tightening, +0p elevated risk), plus life-model years where an answer maps to one (+0y = measured, no effect on its own).

1. How do you sleep most nights: how many hours, and do you snore loudly?

2. Sweaty, heart-rate-raising exercise: how many days a week do you get 30+ minutes?

3. Vegetables and fruit — greens and berries included — how many servings a day?

4. Do you have a strong family history of dementia in close relatives?

5. Have your blood pressure and HbA1c (blood sugar) both been checked, and were they in range?

6. Any persistent memory change that people around you have started noticing?

Now score your own

These two-minute quizzes turn this research into your numbers, and the years they are worth.

Sleep quizFamily history quizExercise quizHeart health quiz

Go deeper in the Wiki

Dementia risk factors: Alzheimer's disease →

Sources

  1. [1]E. Genin et al. APOE and Alzheimer disease: a major gene with semi-dominant inheritance. Mol Psychiatry, 16(9):903-7, 2011. doi:10.1038/mp.2011.52 Evidence: Low
  2. [2]S. Sabia et al. Association of sleep duration in middle and old age with incidence of dementia. Nat Commun, 12(1):2289, 2021. doi:10.1038/s41467-021-22354-2 Evidence: Low
  3. [3]M. C. Morris et al. MIND diet associated with reduced incidence of Alzheimer's disease. Alzheimers Dement, 11(9):1007-14, 2015. doi:10.1016/j.jalz.2014.11.009 Evidence: Low
  4. [4]C. H. van Dyck et al. Lecanemab in Early Alzheimer’s Disease. N Engl J Med, 388(1):9-21, 2023. doi:10.1056/NEJMoa2212948 Evidence: Moderate
  5. [5]R. J. Bateman et al. Clinical and biomarker changes in dominantly inherited Alzheimer's disease. N Engl J Med, 367(9):795-804, 2012. doi:10.1056/NEJMoa1202753 Evidence: Very low
  6. [6]E. Shokri-Kojori et al. β-Amyloid accumulation in the human brain after one night of sleep deprivation. Proc Natl Acad Sci U S A, 115(17):4483-4488, 2018. doi:10.1073/pnas.1721694115 Evidence: Very low
  7. [7]K. I. Erickson et al. Exercise training increases size of hippocampus and improves memory. Proc Natl Acad Sci U S A, 108(7):3017-22, 2011. doi:10.1073/pnas.1015950108 Evidence: Low
  8. [8]J. R. Sims et al. Donanemab in Early Symptomatic Alzheimer Disease: The TRAILBLAZER-ALZ 2 Randomized Clinical Trial. JAMA, 330(6):512-527, 2023. doi:10.1001/jama.2023.13239 Evidence: Moderate

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YapSpan estimates are for reflection and entertainment only. They are not medical advice, a diagnosis, or a prediction of any individual outcome. Check with a doctor before making any medical decision.