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Rapamycin extends mouse lifespan 9–14%
NAD+ precursors reverse aging in humans
Blue-light glasses improve sleep quality
Walking 10 min after meals blunts glucose
Verdict change — caffeine half-life downgraded

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This Supplement Could Cut Your Dementia Risk By 40% — Whalespan

Content›Video›This Supplement Could Cut Yo…

This Supplement Could Cut Your Dementia Risk By 40%

Rhonda Patrick17m · 2025-05-19

Claims Made

40

Claims Supported

39

Support Rate

98%

Support rate

39 of 40 claims supported

39 supported1 partial / not

Claims from this content

18

✓Well SupportedWomen, adults with normal cognition, APOE e4 non-carriers, and those without depression experienced the greatest brain-protective effects from vitamin D supplementation.✓Well SupportedUp to 70% of people in the US are deficient or insufficient in vitamin D, suggesting widespread supplementation is advisable.✓Well SupportedVitamin D influences gene expression by interacting with approximately 20,000-30,000 gene receptors throughout the body.✓Well SupportedTarget vitamin D levels for adequate health are often debated between 30-40 ng/mL, with higher levels like 50-60 ng/mL considered optimal.Well Supported

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Bookmarking — the dossier-vs-overview split is the right call. Most of the time I want overview; sometimes I want receipts.

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✓

A daily intake of 2,000–4,000 IU of vitamin D3 is sufficient for most adults to raise plasma vitamin D levels into the optimal range.

✓Well SupportedCarriers of two copies of APOE4 have a 12-fold increased chance of developing Alzheimer's disease, while carriers of one copy have a two to four-fold increased chance.

✓Well SupportedRoutinely testing vitamin D levels is recommended to fine-tune supplementation dosage.

✓Well SupportedVitamin D supplementation (800 IU daily for one year) improved memory, attention, and IQ in individuals with mild cognitive impairment.

✓Well SupportedGenetically determined low vitamin D levels increase dementia risk by 54%.

✓Well SupportedEach 10 nmol/L increase in vitamin D is associated with a small decrease in white matter hyperintensities, suggesting brain protection.

✓Well SupportedFactors such as sunscreen use, dark skin color, high body fat, and old age can impair vitamin D production from sun exposure.

◐Partially SupportedVitamin D's roles in the brain include clearing amyloid beta plaques and tau buildup, boosting neuron survival, and enhancing brain connectivity, especially with exercise.

✓Well SupportedHaving one APOE E4 allele can double the risk of Alzheimer's disease, and having two alleles can increase the risk up to 4-fold.

◐Partially SupportedVitamin D supplementation for 12 months improved cognitive function, intelligence quotient scores, telomere length, and lowered oxidative stress markers in older adults compared to placebo.

◐Partially SupportedVitamin D acts as an immune modulator in the brain, reducing neuroinflammation by lowering pro-inflammatory cytokine response.

◐Partially SupportedObservational studies show a correlation between low vitamin D levels and dementia risk, but this association may be confounded by other health factors.

◐Partially SupportedNeuroinflammation plays a significant role in the cause of dementia and Alzheimer's disease.

◐Partially SupportedOxidative stress can indirectly lead to inflammatory processes in the brain.