alzhub.org
Get help now — free helplines

You can call any of these for free. You do not need a diagnosis, an appointment, or a crisis to call — questions and plain exhaustion are reasons enough.

  • Alzheimer's Association 24/7 Helpline 800-272-3900 24 hours a day, 365 days a year Free, confidential support and information for people with dementia, caregivers, families and the public. Master's-level clinicians. Also Spanish.
  • 988 Suicide & Crisis Lifeline 988 24/7 Call or text 988, or chat at 988lifeline.org. For anyone in emotional distress or a mental-health crisis, including caregivers.
  • Alzheimer's Foundation of America (AFA) Helpline 866-232-8484 9:00 am - 9:00 pm ET, seven days a week Licensed social workers providing support, info and referrals. Also text message and web chat. Text: 646-586-5283

In a medical emergency, call 911. More numbers, and what each line does, on the help page.

Home › Research › What the research found › Every row

Every row of the evidence table

One row per finding: what was tested, which way the result went, and how the study was built. The answer by area, and where the studies disagree, are on the main page.

Every row

Filter

Area All 382 Care, carers and services 140 Medicines 85 Genes (not modifiable) 35 All modifiable factors together 27 Diet and supplements 23 Exercise and activity 21 Sleep, mood and social life 19 Hearing and vision 8 Alcohol, tobacco and cannabis 6 Infection and vaccination 5 Heart and metabolic health 4 Injury, delirium and falls 4 Environment 3 Cognitive activity 2
Question Both Prevention 190 Treatment 192
Direction Any Benefit 144 Harm 105 No effect 38 Mixed 37 No direction reported 58
Design Any meta-analysis 57 randomised trial 44 phase 3 trial 15 systematic review 9 phase 2 trial 10 cohort study 136 phase 1 trial 2 cross-sectional study 31 case-control study 14 modelling study 20 regulatory decision 7 company announcement 1 coverage determination 1 None 35
Clear all

Showing 8 of 382 rows. One row per study per exposure: a study that tested two different things appears twice, once for each.

Scroll the table sideways to see every column.

Research and outcomes, 8 rows. Every row links to its source.
Exposure Question Direction Outcome measured Design People Effect size, as the source reported it Source
Cognitive training Cognitive activity Prevention No effect
why

Neither the combined package nor risk-factor modification beat health advice.

 ADAS-Cog z-score at 15 months randomised trial 456 ADAS-Cog z-score difference vs health advice: -0.04 (95% CI -0.34 to 0.26) for combined package The Lancet Healthy Longevity 2025
✓ Peer-reviewed PMID 40294622
Dietary pattern (general) Diet and supplements Prevention No effect
why

The control arm also received diet counselling and mild caloric restriction, so this is MIND against another active diet, not against usual eating. It is the only randomised test of the MIND diet here and it disagrees with the cohort evidence.

 Global cognition at 3 years randomised trial 604 Global cognition mean difference 0.035 standardised units (95% CI -0.022 to 0.092; P=0.23) New England Journal of Medicine 2023
✓ Peer-reviewed PMID 37466280
MIND diet Diet and supplements Prevention No effect
why

The control arm also received diet counselling and mild caloric restriction, so this is MIND against another active diet, not against usual eating. It is the only randomised test of the MIND diet here and it disagrees with the cohort evidence.

 Global cognition at 3 years randomised trial 604 Global cognition mean difference 0.035 standardised units (95% CI -0.022 to 0.092; P=0.23) New England Journal of Medicine 2023
✓ Peer-reviewed PMID 37466280
Multidomain lifestyle intervention Exercise and activity Prevention No effect
why

The intervention did not change any brain biomarker trajectory. Participants with lower baseline hippocampal volume did show a greater cognitive benefit.

 Amyloid, tau, hippocampal volume and white matter trajectories randomised trial 983 Cognitive benefit of structured vs self-guided: 0.077 SD (95% CI 0.022-0.132) with lower hippocampal volume vs 0.002 SD (95% CI -0.037 to 0.041) with higher JAMA Neurology 2026
✓ Peer-reviewed PMID 42008251
Multidomain lifestyle intervention Exercise and activity Prevention No effect
why

A small improvement that did not reach significance (adjusted difference 0.06, 95% CI -0.001 to 0.128, p=0.055).

 Neuropsychological Test Battery at 24 months randomised trial 746 Adjusted mean difference in NTB score at 24 months 0.06 (95% CI -0.001 to 0.128, p=0.055) The Lancet Healthy Longevity 2025
✓ Peer-reviewed PMID 41130254
Physical activity (general / dose) Exercise and activity Prevention No effect
why

Neither the combined package nor risk-factor modification beat health advice.

 ADAS-Cog z-score at 15 months randomised trial 456 ADAS-Cog z-score difference vs health advice: -0.04 (95% CI -0.34 to 0.26) for combined package The Lancet Healthy Longevity 2025
✓ Peer-reviewed PMID 40294622
Resistance training Exercise and activity Prevention No effect
why

The primary outcome did not move between groups. Attention and inhibitory control did improve (SMD 0.43), as did muscular strength.

 Executive function at 24 weeks (primary) randomised trial 90 Between-group executive function SMD 0.13 (P=0.37); attention/inhibitory control SMD 0.43 (P<0.001) Alzheimer's & Dementia 2026
✓ Peer-reviewed PMID 41562376
Hearing loss / hearing aids Hearing and vision Prevention No effect
why

Null in the primary analysis of the whole cohort. The prespecified analysis of the higher-risk ARIC subgroup found less decline, which the authors present as hypothesis-generating rather than as a result.

 3-year global cognition (primary analysis) randomised trial 977 Primary analysis: "3-year cognitive change (in SD units) was not significantly different between HI and SA control (HI: -0.200 [95% CI: -0.256, 0.144]; SA: -0.202 [95% CI: -0.258, -0.145]; Difference 0.002 [95% CI: -0.077, 0.081], p=0.96)." ARIC subgroup: "HI was associated with a 48% reduction in 3-year cognitive change compared to SA control (Difference 0.191 [95% CI: 0.022, 0.360], p=0.027)." The Lancet 2023
✓ Peer-reviewed PMID 37478886

How this table was built, and where it is weak →