Vitamin D deficiency increases risk of Dementia by 1.4 X and Alzheimer’s by 1.5 X – Meta-analysis March 2024

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Association of Vitamin D Levels with Risk of Cognitive Impairment and Dementia: A Systematic Review and Meta-Analysis of Prospective Studies

Journal: Journal of Alzheimer's Disease, March 2024 DOI: 10.3233/JAD-231381
Zhang, Xiao-Xuea; b | Wang, He-Ranb | Hu, Ya-Zhuob | Sun, Hong-Meia; b | Feng, Yu-Xina; b | Jia, Jian-Juna; b; *

Background: Emerging evidence suggests the potential relationship between vitamin D deficiency and risk of cognitive impairment or dementia. To what extent the excess risk of dementia conferred by vitamin D deficiency is less clear. Objective: We summarized the current evidence from several aspects and further quantified these associations.

Methods: We collected relevant prospective cohort studies by searching PubMed, Embase and Cochrane up to July 2023. The pooled relative risks (RR) were evaluated by random-effects models. Dose-response analyses were conducted by the method of two-stage generalized least squares regression.

Results: Of 9,267 identified literatures, 23 were eligible for inclusion in the meta-analyses, among which 9 and 4 literatures were included in the dose-response analyses for the risk of dementia and Alzheimer’s disease (AD).

• Vitamin D deficiency exhibited a 1.42 times risk for dementia (95% confidence interval (CI) = 1.21–1.65) and a
• 1.57-fold excess risk for AD (95% CI = 1.15–2.14).

And vitamin D deficiency was associated with 34% elevated risk with cognitive impairment (95% CI = 1.19–1.52). Additionally, vitamin D was non-linearly related to the risk of dementia (p nonlinearity = 0.0000) and AD (p nonlinearity = 0.0042). The approximate 77.5–100 nmol/L 25-hydroxyvitamin D [25(OH)D] was optimal for reducing dementia risk. And the AD risk seemed to be decreased when the 25(OH)D level >40.1 nmol/L.

Conclusions: Vitamin D deficiency was a risk factor for dementia, AD, and cognitive impairment. The nonlinear relationships may further provide the optimum dose of 25(OH)D for dementia prevention.
 Download the preprint from VitaminDWiki

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VitaminDWiki – Overview Alzheimer's-Cognition and Vitamin D contains:

• FACT: Cognitive decline is 19X more likely if low vitamin D
• FACT: Dementia is associated with low vitamin D levels.
• FACT: Alzheimer’s Dementia 2.3X more likely in elderly if low vitamin D – Dec 2022
• FACT: Dementia is associated with low vitamin D - many studies
• FACT: Alzheimer's Disease is 4X less likely if high vitamin D
• FACT: Every single risk factor listed for Alzheimer's Disease is also a risk factor for low vitamin D levels
• FACT: Elderly cognition gets worse as the elderly vitamin D levels get even lower (while in senior homes)
• OBSERVATION: Reports of increased vitamin D levels result in improved cognition
• OBSERVATION: Alzheimer’s patients 3X more likely to have a malfunctioning vitamin D receptor gene – 2012
• OBSERVATION: Alzheimer's Disease has been seen to halt when vitamin D was added.
• OBSERVATION: Alzheimer’s is associated with all 7 of the genes which restrict vitamin D
• OBSERVATION: 39 vitamin D and Alz. or Cognition intervention trials as of Sept 2018
• OBSERVATION: 2 Meta-analysis in 2012 agreed that Alzheimer's Disease. associated with low vitamin D
• OBSERVATION: 50X increase in Alzheimer's while decrease in vitamin D
• OBSERVATION: Vitamin D reduces Alzheimer’s disease in 11 ways
• OBSERVATION: Alzheimer’s cognition improved by 4,000 IU of vitamin D
• OBSERVATION: Plaque removed in mice by equiv. of 14,000 IU daily
• OBSERVATION: DDT (which decreases Vit D) increases risk of Alzheimer's by up to 3.8X
• OBSERVATION: 2% of people have 2 copies of the poor gene reference: Alz Org
• OBSERVATION: Genes do not change rapidly enough to account for the huge increase in incidence
• OBSERVATION: End of Alzheimer's videos, transcripts and many studies protocol has been very successful
  • It adjusts Vitamin D, B-12, Iron, Omega-3, food, etc, and can now be done at home.
• FACT: Vitamin D is extremely low cost and has very very few side effects
• CONCLUSION: Everyone concerned about cognitive decline or Alzheimer's Disease should take vitamin D
• PREDICTION MET: By 2024 Omega-3 and high dose Vitamin D will be found to reverse Alzheimer's in humans
  There are 13+ Alzheimer’s meta-analyses in VitaminDWiki
  There are 97+ Alzheimer’s studies in VitaminDWiki
  Dementia is associated with low vitamin D - many studies 50+ studies
  16+ studies in both categories Cognitive and Omega-3

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VitaminDWiki – Cognitive category contains:

Very brief summary of Cognitive decline
Treatment : Vitamin D intervention slows or stops progression
Prevention : Many observational studies - perhaps Vitamin D prevents
Omega-3 both prevents and treats cognition
Wonder the benefits if both Vitamin D AND Omega-3 were to be used
Dementia page - 50 items

373 items in Cognition category

see also Overview Alzheimer's-Cognition and Vitamin D
Overview Parkinson's and Vitamin D

Studies in both categories of Cognition and:
Cardiovascular (7 studies), Genetics (9 studies), Vitamin D Receptor (16 studies), Omega-3 (49 studies), Intervention (19 studies), Meta-analyses (22 studies), Depression (23 studies), Parkinson's (22 studies)
Click here for details

Poor cognition 26 percent more likely if low Vitamin D (29 studies) – meta-analysis July 2017
Every schizophrenia measure was improved when vitamin D levels were normalized – June 2021
Cognitive Impairment and Dementia often associated with low Vitamin D – April 2020
IQ levels around the world are falling (perhaps lower Vitamin D, Iodine, or Omega-3)
Search VitaminDWiki for "WHITE MATTER" 325 items as of March 2023

Types of evidence that Vitamin D helps brain problems - 2014

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VitaminDWiki – Dementia is associated with low vitamin D - many studies

Which as of March 2024 contained
Vitamin D reduced Dementia in VA by 40% - Dr. Campbell March 2023
57+ Vitamin D pages containing "Dementia" in title
VitaminDWiki - Overview Alzheimer's-Cognition and Vitamin D
Dementia 1.8X more likely if low Vitamin D - April 2022
Vitamin D deficiency as a risk factor for dementia: a systematic review and meta-analysis - 2017
Quality assessment of systematic reviews of vitamin D, cognition and dementia - 2018
VITAMIN D AND DEMENTIA - 2016
How to Communicate With People Suffering From Dementia - April 2022 - nothing about Vitamin D
Dementia is also associated with Magnesium
Dementia risk increased 1.5X to 1.9X: depends on type of laxative used - Feb 2023
32,000 hits for the search: dementia (latitude OR sunshine)

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Grassrootshealth report and chart on the study March 2024

GRH