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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

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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
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Showing 8 of 382 rows for Dietary pattern (general). 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
Dietary pattern (general) Diet and supplements Prevention Benefit
why

The association is reported in people who already have elevated Alzheimer's blood markers, which is the point of the study.

 Incident dementia over a mean 8.4 years cohort study 1,865 Dementia HR 0.71 (95% CI 0.58-0.88) per SD of anti-inflammatory diet adherence among participants with elevated p-tau217 JAMA Network Open 2026
✓ Peer-reviewed PMID 42348207
Dietary pattern (general) Diet and supplements Prevention Benefit
why

Direction is for a healthier plant-based diet: higher overall and healthful plant-based diet scores were associated with lower dementia risk, while a higher unhealthful plant-based diet score was associated with higher risk (pooled HR 1.42).

 Incident dementia by plant-based diet index (overall, healthful and unhealthful) meta-analysis 207,981 higher scores in PDI and hPDI were associated with lower risk of dementia (highest vs. lowest tertile: pooled HR for PDI = 0.70, 95% CI, 0.53-0.92, p for trend <0.001; pooled HR for hPDI = 0.71, 0.48-1.06, p for trend = 0.03) ... higher uPDI was associated with higher dementia risk (highest vs. lowest tertile: pooled HR = 1.42, 1.19-1.70, p for trend <0.001). In the meta-analysis, individuals in the highest hPDI tertile had 21% lower dementia risk, and those in the highest uPDI tertile had 24% higher risk The journal of prevention of Alzheimer's disease 2026
✓ Peer-reviewed PMID 41564649
Dietary pattern (general) Diet and supplements Prevention Benefit
why

Independent of overall diet quality. Substituting olive oil for margarine or mayonnaise was also associated with lower risk; substituting for butter or other vegetable oils was not.

 Dementia-related death over 28 years cohort study 92,383 HR 0.72 (95% CI 0.64-0.81) for dementia-related death with ≥7 g/day olive oil vs never/rarely JAMA Network Open 2024
✓ Peer-reviewed PMID 38709531
Dietary pattern (general) Diet and supplements Prevention Benefit
why

Pooled observational studies only.

 Dementia and Alzheimer's disease meta-analysis 65,955 Pooled OR 0.89 (95% CI 0.84-0.94) for dementia; cohort HR 0.84 (0.76-0.94); Alzheimer's OR 0.73 (0.62-0.85) Aging Clinical and Experimental Research 2024
✓ Peer-reviewed PMID 38519775
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
Dietary pattern (general) Diet and supplements Prevention Benefit
why

Observational. Points the opposite way to the randomised MIND diet trial.

 Incident dementia meta-analysis 224,049 HR 0.83 per 3-point MIND-score increment (95% CI 0.72-0.95); highest vs lowest tertile HR 0.83 (0.76-0.90) JAMA Psychiatry 2023
✓ Peer-reviewed PMID 37133875
Dietary pattern (general) Diet and supplements Prevention Benefit
why

Significant on one adherence score (MEDAS, HR 0.77) but not the other (PYRAMID, HR 0.86, 95% CI 0.73-1.02).

 Incident dementia over a mean 9.1 years cohort study 60,298 HR 0.77 (95% CI 0.65-0.91) for highest vs lowest MEDAS tertile BMC Medicine 2023
✓ Peer-reviewed PMID 36915130
Dietary pattern (general) Diet and supplements Prevention Benefit
why

Controls declined while the olive-oil arm held steady; the nut arm fell between the two. Cognitive follow-up was available for 334 of 447 enrolled.

 Global cognition composite at median 4.1 years randomised trial 447 Global cognition composite: +0.05 (95% CI -0.11 to 0.21) olive-oil arm vs -0.38 (-0.57 to -0.18) control; P=0.005 JAMA Internal Medicine 2015
✓ Peer-reviewed PMID 25961184

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