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#102 Why Vitamin D Deficiency Accelerates Brain Aging

May 21, 2025 17m 15s 14 insights
<p><a href="https://www.foundmyfitness.com/aliquot?utm_campaign=vitamin_d_dementia_podcast&amp;utm_medium=podcast&amp;utm_source=podcast_description"> Discover my premium podcast, <strong>The Aliquot</strong></a></p> <p dir="ltr">Vitamin D is far more than just a vitamin—it's a potent steroid hormone regulating nearly 5% of our genome. Yet, remarkably, up to 70% of Americans aren't getting enough, placing them at increased risk for dementia and Alzheimer's disease. In this episode, I explore compelling new evidence from a study involving over 12,000 participants, demonstrating that vitamin D supplementation can reduce dementia risk by an impressive 40%, protecting even adults with genetic Alzheimer's risk (ApoE4 carriers).</p> <p><strong>Timestamps:</strong></p> <ul> <li><strong>(00:00)</strong> Can vitamin D supplements reduce dementia risk?</li> <li><strong>(00:46)</strong> How common is vitamin D deficiency?</li> <li><strong>(03:31)</strong> What studies reveal about genes, vitamin D, and dementia</li> <li><strong>(05:44)</strong> Does deficiency accelerate brain aging?</li> <li><strong>(06:45)</strong> Can vitamin D supplementation enhance cognitive function?</li> <li><strong>(08:15)</strong> Dementia risk reduction insights from 12,388 adults</li> <li><strong>(09:58)</strong> Why women may benefit most</li> <li><strong>(10:49)</strong> Normal vs. impaired cognition—who benefits more from vitamin D?</li> <li><strong>(11:21)</strong> Do ApoE4 carriers get dementia protection from vitamin D?</li> <li><strong>(13:00)</strong> How mild cognitive impairment affects dementia risk</li> <li><strong>(13:41)</strong> Does the form of vitamin D matter?</li> <li><strong>(14:11)</strong> What are the optimal vitamin D blood levels?</li> <li><strong>(15:07)</strong> What dose corrects deficiency?</li> <li><strong>(15:33)</strong> How vitamin D directly supports brain function</li> </ul> <p><a href="https://www.youtube.com/watch?v=tpFOA1AUFCk">Watch this episode on YouTube</a></p> <p><a href="https://www.foundmyfitness.com/episodes/vitamin-d-dementia?utm_campaign=vitamin_d_dementia_podcast&amp;utm_medium=podcast&amp;utm_source=podcast_description"> Show notes are available by clicking here</a></p> <p>The study discussed: <a href="https://alz-journals.onlinelibrary.wiley.com/doi/10.1002/dad2.12404" rel="noopener" target="_blank">Vitamin D supplementation and incident dementia: Effects of sex, APOE, and baseline cognitive status</a></p>
Actionable Insights

1. Test Vitamin D Levels

Get a simple blood test to measure your 25-hydroxyvitamin D levels, as deficiency or insufficiency is widespread, affecting up to 70% of people.

2. Maintain Optimal Vitamin D

Aim to keep your 25-hydroxyvitamin D blood levels between 30 to 60 nanograms per milliliter, and avoid going above 80 nanograms per milliliter.

3. Combat Vitamin D Deficiency

Take a vitamin D supplement to avoid deficiency (below 20 ng/mL) or insufficiency (20-30 ng/mL), which affects up to 70% of Americans.

4. Daily Vitamin D Dosage

If vitamin D deficient, take around 2,000 to 4,000 IUs of vitamin D per day to reach a sufficient level.

5. General Vitamin D Maintenance

Most people can take 2,000 to 4,000 IUs of vitamin D daily to maintain levels within the 40 to 60 ng/mL range, adjusting based on blood test results.

6. Annual Vitamin D Check

Conduct an annual vitamin D blood test to ensure you are taking an appropriate amount, avoiding both excessive intake and insufficient levels.

7. Supplement Vitamin D for Dementia

Supplementing with vitamin D was associated with a 40% lower risk of dementia over a decade, with 84% of supplement users being dementia-free after five years.

8. Supplement Early for Dementia

Begin vitamin D supplementation while cognitively healthy for a more robust effect, as those with normal baseline cognitive function saw a 56% lower dementia incidence.

9. Vitamin D Benefits All Adults

Supplement with vitamin D as it provides benefits for lowering dementia risk regardless of whether you have normal cognitive function or mild cognitive impairment at baseline.

10. Protect Brain White Matter

Aim for higher vitamin D levels, as every 10 nanomole per liter increase was associated with a decrease in white matter hyperintensities, indicating protection against brain damage.

11. Improve Cognition (MCI/AD)

If diagnosed with mild cognitive impairment or Alzheimer’s disease, take around 800 IUs of vitamin D daily for over a year to potentially improve memory, attention, and overall IQ.

12. Reduce Amyloid Beta Pathology

Supplementing with vitamin D (e.g., 800 IUs/day) can reduce blood biomarkers of amyloid beta pathology, which is associated with Alzheimer’s disease progression.

13. Vitamin D for ApoE4 Carriers

Supplementing with vitamin D can reduce dementia risk by around 33% in adults carrying the ApoE4 genetic risk factor, a key factor for neurodegenerative diseases.

14. Women Prioritize Vitamin D

Women may derive greater benefits from vitamin D supplementation for dementia risk, experiencing almost a 50% lower incidence compared to non-using women.