STEM Library Science Blog: Vitamin D May Prevent Alzheimer's & Dementia

Does Vitamin D-Deficiency

Result in Alzheimer’s & Other

Neurocognitive Disorders?

Evelyn Smith (M. S. in Library Science, University of North Texas, 2012)

The body’s delicate; [this] tempest in my mind

Doth from my senses take all feeling else . . . .

King Lear III, iv, 13-14

Edited and Added to February 17, 2016

Medical Studies Linking Vitamin D Deficiency with Alzheimer’s

On August 6, 2014, the August issue of Neurology published a groundbreaking longitudinal study that linked the risk of developing Alzheimer’s and other dementias with low levels of vitamin D in the blood. While correlation doesn’t equate with causation, this research publicized the use of vitamin D supplements and omega-3 fatty acid as possible means of delaying and/or preventing cognitive decline. All of which also suggests that older adults need to up their intake of vitamin D as a preventive measure just as they need to get enough exercise, eat a healthy, balanced diet, and maintain a support group of close friends.

For an earlier take on the general benefits of vitamin D, go to Shining the light on the benefits of vitamin D. (2013, March 7). STEM Library Science Blog. Retrieved from https://www.blogger.com/blogger.g?blogID=2149812825538872690#editor/target=post;postID=970504028190340250;onPublishedMenu=posts;onClosedMenu=posts;postNum=15;src=postname

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A Sampling of Bibliographic Sources on

Vitamin D Deficiency and Dementia

Littlejohns, T., Henley, W. E, & Lang, I. A., et al. (2014, August 6). Vitamin D and the risk of dementia and Alzheimer disease. Neurology. doi: 10.1212/WNL.0000000000000755 [Abstract only]. [Open Access via Neurology]. Retrieved from http://www.neurology.org/content/early/2014/08/06/WNL.0000000000000755.abstract

Researchers obtained blood samples from 1, 658 ambulatory older adults between 1992-1993 and 1999 as part of a Cardiovascular Health Study, first obtaining serum 25-hydroxyvitamin D concentration levels through liquid chromatography-tandemass spectrometry in 1992-1993 and then conducting a follow-up assessment in 1999 to determine if the participants had developed Alzheimer’s or dementia in the intervening years. They discovered that the 102 participants who had developed Alzheimer’s were severely deficient in vitamin D compared with those who had healthy amounts of vitamin D3 in their blood. The research thus associated vitamin D deficiency with a “substantially increased risk” of Alzheimer’s and other types of dementia (Littlejohn, 2014, August 6, Abstract, para. 1-4).

An online publicity post publicizes, summarizes, and enumerates the findings of the August 2014 Neurology article:

Littlejohns, T., Soni, M., and Annweiler, C. et al. (2014). Vitamin D and incident Alzheimer’s Disease in the cardiovascular health cognition study. [Abstract]. University of Exeter Medical School. Retrieved from https://medicine.exeter.ac.uk/media/universityofexeter/medicalschool/research/healthservicesresearch/docs/Littlejohns__AAIC_Poster.pdf

After collecting and analyzing blood samples for serum 25 (OH) D in a sample of adults who were age 64 or older in 1992-1993, researchers over a mean follow-up period of five to six years determined that the risk of Alzheimer’s was 60 percent higher in those participants whose blood was severely lacking in vitamin D [here the researchers round off the percentages]. Consequently, clinical trials are needed to tell whether vitamin D supplements prevents Alzheimer’s in older adults. The study, however, needs to be studied within the context of previous research that also associates the risk of Mild Cognitive Impairment, late-onset Alzheimer’s, and other types of dementia in older adults with low levels of vitamin D3 in the blood.

Annweiler, C., and Bequchet, O. (2011). Vitamin D-mentia. Randomized clinical trials should be the next step. Neuroepidemiology, 37 (3-4), pp. 249-55. doi: 10.1159/000334177. [Free full text]. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/22156654

Since taking vitamin D supplements might possibly stabilize Alzheimer's or prevent age-related cognitive decline, Annweiler and Bequchet call for randomized, clinical trials comparing the results of administering a vitamin D supplement and a placebo and their effects on cognitive impairment and Alzheimer's. Cross-sectional studies have associated Vitamin D intake from diet, sun exposure, and supplements have strengthened the hypothesis that Vitamin D preserves cognitive function, but they can't show the empirical evidence that proves a cause and effect link (Annweiler, Abstract only, p. 249).

Annweiler C., Dursun E. and Féron F. et al. (2014, July 18). Vitamin D and cognition in older adults’: Updated international recommendations. Journal of Internal Medicine. [Abstract only]. doi: 10.1111/joim.12279. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/24995480

Annweiler, C., Fantino, B., and Schott, A. M., et al. (2012, July). Vitamin D insufficiency and mild cognitive impaimentcross-sectional association. Euuropean Journal of Neurology, 19 (7), pp.1023-29. doi: 10.1111/j.1468-1331.2012.03675.x. [Abstract only]. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/22339714

After comparing community-dwelling, cognitively healthy individuals with those with subjective memory complaints, French researchers discovered that older women complaining of memory loss were more likely to have lower concentrations of low serum 25 hydroxyvitamin D in their blood (Annweiler, 2012, July, Abstract, p. 1023).

Annweiler, C., Llewellyn, D., J., and Beauchet, O. (2013). Low serum vitamin D concentrations in Alzheimer's disease: A systematic review and meta-analysis. Journal of Alzheimer's Disease: JAD, 33 (3), pp. 659-74. [Abstract only]. doi: 10.3233/JAD-2012-121432. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/23042216

A Medline and PsycINFO search in May 2012 generated a meta-analysis that confirmed that adults diagnosed with Alzheimer's had lower serum levels of vitamin D levels in their blood that their matched controls (Annweiler, 2013, Abstract, p. 659).

Annweiler, C., Rolland, Y. and Schott, A. M., et al. (2012, November). Higher vitamin D dietary intake is associated with lower risk of Alzheimer's disease: A 7-year follow-up. The Journals of Gerontology. Series A: Biological Sciences and Medical Sciences, 67 (11), 1205-11. doi: 10.1093/gerona/gls107. [Abstract only]. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/22503994

A Toulouse, France, cohort study divided 498 community-dwelling women, aged 75 and younger, who were free of vitamin D supplements, and measured their baseline vitamin D intake based upon a self-reported food-frequency questionaire. Those women with a lower baseline of Vitamin D intake were more likely to have developed Alzheimer's seven years later. Conversely, those women who reported a higher level of Vitamin D intake based on their dietary choices were less likely to be diagnosed with Alzheimer's (Annweiler, 2012, November, Abstract, p. 1205).

Assman, K. E., Touvier, M., and Andreeva,V. A., et al. (2015, May 28). Midlife plasma vitamin D concentrations and performance indifferent cognitive domains assessed 13 years later. The British Journal of Nutrition, 113 (10), pp. 1628-37. [Abstract only]. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/25864611

After measuring concentrations of 25-Hydroxyvitamin D in plasma samples in French adults, aged 40 to 60 years between 1994 and 1995 and then evaluating their cognitive performance between 2007 to 2009, researchers discovered a positive association between sufficient Vitamin D intake in midlife and short-term working memory, although additional years of formal education might also equip better educated adults with a cognitive reserve (Assman, 2015, May 28, Abstract, p. 1628).

Annweiler C., Dursun, E. and Féron F. et al. (2014, July 18). Vitamin D and cognition in older adults’: Updated international recommendations. Journal of Internal Medicine. [Abstract only]. doi: 10.1111/joim.12279. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/24995480

Hypovitaminosis D, or a deficiency in vitamin D, increases the risk of dementia in older adults, even though the testing for a lack of vitamin D shouldn’t be used as a diagnostic tool or bio-marker of Alzheimer’s at this time, according to researchers attending an international, invitational conference on “Vitamin D and Cognition in Older Adults”. Nevertheless, adults over age 65 should be regularly screened for Vitamin D deficiency (Annweiler, 2014, July 18, Abstract, para. 1-4).

Balion C., Griffith, L. E., and Strifler L., et al. (2012, September 25). Vitamin D, cognition, and dementia: a systematic review and meta-analysis. Neurology, 79 (13), pp. 1397-405. [Abstract]. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/23008220

After searching five English-language databases up to August 2010, researchers found 37 studies that found that vitamin D exerted a positive effect in preventing Alzheimer’s. Conversely, this survey connected lower vitamin D levels with “poorer cognitive function” and a “higher risk of AD” (Balion, 2012, September 25, Abstract, p. 1397).

Brouwer-Brolsma, E. M., and deGroot, L.C. (2015, January). Vitamin D and cognition in older adults: An update of recent findings. Current Opinion in Clinical Nutrition and Metabolic Care, 18 (1), pp. 11-6). doi: 10.1097/MCO.0000000000000114. [Abstract only]. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/25225898

Recent research posits that vitamin D helps in the sending and creation of neurons as well as their synaptogenesis, the clearing of amyloid plaque, and the prevention of neuron death. Observational studies have also associated higher serum levels of vitamin D with better cognitive performance, although imaging studies and randomized trials are “scarce” (Brouwer-Brolsma, 2015, January, Abstract, p. 11).

Dickens, A. P., Lang, I. A, and Laga, K. M., et al. (2011, August). Vitamin D, cognitive dysfunction and dementia in older adults. CNS Drugs, 25 (8), pp. 629-39. doi: 10.2165/11593080-000000000-00000. [Abstract only]. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/21790207

While medical science has long associated insufficient vitamin D with osteoporosis and has recently correlated low levels of vitamin D with cancer, heart disease, stroke, and type-2 diabetes, recent research has associated low levels of vitamin D with an increased risk of cognitive dysfunction and Alzheimer's: For example, the risk of cognitive decline was 60 percent higher in Italian males with severely deficient vitamin D levels, and the risk of developing Alzheimer's was 41 percent higher in American men with low levels of vitamin D (Dickens, 2011, August, Abstract, p. 629).

Dursun E, Gezen-Ak D, & Yilmazer S. (2011). A novel perspective for Alzheimer's disease: Vitamin D receptor suppression by amyloid-β and preventing the amyloid-β induced alterations by vitamin D in cortical neurons. Journal of Alzheimer’s Disease, 23 (2), pp. 207-19. doi: 10.3233/JAD-2010-101377. [Abstract only]. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/24413618

While Amyloid-β (Aβ) (or the amino acids that form the amyloid plaques associated with Alzheimer’s) triggers gene mutations that result in the loss of the neurons that transmit messages within the brain, vitamin D protects neurons in the cerebral cortex by preventing cell damage and cell death (Dursun, 2011, Abstract, p. 207).

Cognitively normal and brains filled with amyloid-beta plaque compared

Fiala, M. & Mizwicki, M. T. (2011). Neuroprotective and immune effects of active forms of vitamin D3 and docosahexaenoic acid in Alzheimer disease patients. Functional Foods in Health and Disease, 12, pp. 545-554. [Open Access]. Retrieved from http://www.functionalfoodscenter.net/files/48097603.pdf

Because the skin of older adults absorbs less sunlight than it did when they were younger, and/or they are less likely to send time in the sun, many older adults get less vitamin D than they did when they were younger, and they don’t eat enough fatty fish and fresh fruits and vegetables. These factors might make them more susceptible to Alzheimer’s disease. Preventing Alzheimer’s disease therefore might in part boil down to simple changes in diet: Avoiding simple carbohydrates, like sugar, and consuming more complex carbohydrates, like green vegetables, whole grains, starches, and lentils, avoiding saturated fat, and regularly including vitamin D, which is mostly found in omega-3 fatty fish, in the diet. Vitamin D acts as a neuro-protective agent since it clears out amyloid-beta plaque and inhibits the process of amyloid-precursor protein, inflammatory toxics, and cell death. An increased consumption of vitamin D and fish oil might prevent the degeneration of neurons in the outer brain (Fiala, 2011, Abstract, p. 545).

Gezen-Ak, D., Yılmazer, S., and Dursun, E. (2014). Why vitamin D in Alzheimer's disease? The hypothesis. Journal of Alzheimer’s Disease, 40 (2), pp. 257-69. doi: 10.3233/JAD-131970. [Abstract only]. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/24413618

Researchers posit that vitamin D protects the nervous system, and they suggest that disrupting vitamin D pathways mimics amyloid pathology. Furthermore, they hypothesize that Alzheimer’s disease might be the result of a long-time hormonal imbalance wherein there is a deficiency in vitamin D (Gezen-Ak, 2014, Abstract, p. 257).

Gezen-Ak, D., Dursun, E., Yilmazer, S. (2012, December 19). Vitamin D inquiry in hippocampal neurons: consequences of vitamin D-VDR pathway disruption on calcium channel and the vitamin D requirement. Neurological Sciences, 34(8), pp. 1453-1458. doi: 10.1007/s10072-012-1268-6. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/23250517

The vitamin D receptor (VDR) and the enzymes involved in activating the effects of vitamin D are most likely to affect the brain’s hippocampus. Here amyloid beta (Aβ) pathology depletes VDR protein depletion and disrupts vitamin D-VDR pathways. Using rat embryos, researchers have determined that in older adults a greater gene expression of 24OHase and VDR might call for a "higher requirement of vitamin D" in the hippocampus to prevent cognitive decline (Gezen-Ak, 2012, December 19, Abstract, p. 1453).

Gezen-Ak, D., Dursun, E., & Bilgiç B, et al,. (2012, October 16). Vitamin D receptor gene haplotype is associated with late-onset Alzheimer's disease. Tohoku Journal of Experimental Medicine, 228 (3), 189-96. Retrieved from http://aja.sagepub.com/content/26/7/511.abstract

The continuing degeneration of the neurons in the neo-cortex correlates with a high incidence of vitamin D deficiency, which also causes depression and impaired cognitive performance in late-onset Alzheimer’s. Vitamin D3 improves cognitive function in patients with Alzheimer’s because of its active form of vitamin D3 metabolite and its receptor in the central nervous system (Gezen-Ak, 2012, October 16, Abstract, p. 228).

Kapoor, S. (2014, August). Influence of vitamin D consumption and levels on the development of psychiatric disorders. Journal of Clinical Psychopharmacology, 34 (4), pp. 538-539. doi: 10.1097/JCP.0000000000000169. Retrieved from http://journals.lww.com/psychopharmacology/Citation/2014/08000/Influence_of_Vitamin_D_Consumption_and_Levels_on.32.aspx

Getting enough vitamin D not only prevents Alzheimer’s in the elderly, but an increased consumption of vitamin D by mothers during pregnancy and in infants during the first year of life might prevent schizophrenia in young adulthood most particularly in individuals of sub-Saharan African descent (Kapoor, 2014, August Abstract, p. 538).

Getting enough vitamin E is essential for health throughout life.

Llewellyn, D. J., Lang, I., and A. Lang, et al. (2010, July 12). Vitamin D and risk of cognitive decline in elderly persons. Archives of Internal Medicine, 170 (13), pp. 1135-1141. doi. 10.1001/archintermed.2010.173. [Open Access]. Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4053858/

Researchers have shown a correlation between low levels of vitamin D3 (25-hydroxyvitamin D) and an increased rise of cognitive decline in 858 Italian adults aged 65 and older between 1988 and 2006. They first took blood samples, testing for levels of vitamin D in the blood, and later asked volunteers questions from the Mini-Mental State Examination (MMSE), and interviewed them in follow-up assessments every three years (Llewellyn, 2010, July 12, Abstract para. 2). This procedure associated low levels of vitamin D with progressive cognitive decline particularly in older women (Llewellyn, 2010, July 12, Abstract, para. 4).

Llewellyn, D. J., Lang, I. A., and Melzer, D. (2011, January). Vitamin D and cognitive impairment in the elderly U.S. population. The Journals of Gerontology Series A: Biological Sciences and Medical Sciences, 66S (1), pp. 59-65. [Open Access]. Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3011960/

Since recent European research has associated vitamin D deficiency with cognitive decline, this study investigated a possible tie between the lack of vitamin D in blood samples and dementia in adults in the United States aged 65 and older. A nationally representative cross study of 3,325 non-institutionalized older American showed significantly lower levels of serum hydroxyl-vitamin D in those whose mental acuity testing disclosed increased cognitive impairment, shown by impaired immediate and delayed memory, problems with orientation and a lower attention span. These findings call for the exploration of a possible causal relationship between vitamin D deficiency and the onset of Alzheimer’s disease (Llewellyn, 2011, January, Abstract, para. 1-4).

Miller, J. W., Harvey, D. J., and Beckett, L. A., et al. (2015, November). Vitamin D status and rates of cognitive decline in a multiethnic cohort of older adults. JAMA Neurology, 72(11), pp. 1295-1303. doi.10.1001/jamameurol.2015.2115. [Abstract only]. Retrieve from http://archneur.jamanetwork.com/article.aspx?articleid=2436596

In a longitudinal, multi-ethnic study that took place between February 2002 and August 2010, research associated low vitamin D status with accelerated decline in episodic memory and executive functioning, most particularly in African American and Hispanic older adults. However, Vitamin D status didn’t significantly affect semantic memory or visuospatial ability.

Pogge, E. (2010, July). Vitamin D and Alzheimer's disease: is there a link? Consultant Pharmacist, 25 (7), pp. 440-50. doi: 10.4140/TCP.n.2010.440. [Abstract only]. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/20601349

After entering the key words vitamin D, Alzheimer disease, and Vitamin D in the Medline/ PubMed database for sources published between January 1950 and January 2010 and the ISI Web of Science database for articles published between January 1900 and January 2010 as well as reviewing The Cochrane Library and clinical trials.gov to identify unpublished research, Pogge determined that not only is vitamin D deficiency a widespread and long-standing problem in the elderly, but that researchers have recently linked it with dementia, and most particularly Alzheimer’s disease. Hence, Pogge calls on further trials with a longer follow-up period to determine if a cause and effect relationship exists between a lack of vitamin D in the blood and a diagnosis of Alzheimer’s (Pogge, 2010, July, Abstract, p. 440).

Schlögl, Mathias & Holick, Michael F. (2014). Vitamin D and neurocognitive function. Clinical Interventions in Aging, 9, pp. 559-588. [Open Access]. Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3979692/

Recent emerging evidence has not only linked vitamin D deficiency with calcium-depleted bones and osteoporosis, but it has also correlated it with Mild Cognitive Impairment and late-onset Alzheimer’s. An increasing proportion of the elderly in developed countries with low levels of vitamin D in the blood, in turn, enhances the importance of these findings. A lack of vitamin D in the diet along with a decreased inability for the skin to synthesize sunlight into vitamin D as individuals grow older results in this insufficiency (Schlögl, 2014, Abstract, p. 559).

Shah, I., Petroczi, A., & Tabet, N. (2012, November 9). Low 25OH Vitamin D2 levels found in untreated Alzheimer’s patients, compared to Acetylcholinesterase inhibitor treated and controls. Current Alzheimer Research, 9 (9), pp.1069-1076. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/22876849\

This study contrasts the levels of 25-hydroxyvitamin D (25-OH), or calcidiol, in the blood of Alzheimer’s patients treated with acetylcholinesterase inhibitors as well as those Alzheimer’s patients not treated with donepezil, rivastigmine or galantamine, and a control group that didn’t show any signs of cognitive impairment The levels of 25-OH as well as 1,25-dihydroxyvitamin D, or calcitrol, were significantly lower in the untreated group when compared to those patients prescribed acetylcholinesterase inhibitors and their cognitively healthy controls. The reader will also find that browsing the interpretation of medical references on vitamin D and cognitive decline in popular, non-medical sources particularly helpful (Shah, 2012, November 9, Abstract, p. 1069).

These comparisons also point out the occasional over simplification of complex medical issues, although some more insightful articles provide hyperlinks to PubMed abstracts and Open Access sources if their audience wants to verify or further explore a particular study’s findings. A comparison of these studies is important since it emphasizes that maintaining a high level of vitamin D is just one of the tactics that older adults might use to delay or prevent the onset of dementia, including getting enough physical exercise, not succumbing to depression, and striving for happiness with the help of a caring support group of friends. Western medicine, however, often forgets that a form of vitamin D3 is found in curcumin (turmeric), a key ingredient found in curry powder(Shah, 2012, November 9, Abstract, p. 1069).

See also:

Mishra, S. and Palanivelu. (2008, January-March). The effect of curcumin (turmeric) on Alzheimer’s disease. Annals of Indian Academy on Neurology, 11 (1), pp. 13-19. Retrieved from http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2781139/

Indian medicine has extensively studied curcumin (turmeric), for treatment of dementia and brain injury. This antioxidant and anti-inflammatory herb used in curry powder improves the cognitive function of Alzheimer’s patients since it shrinks amyloid beta plaques, delays the breaking down of neurons, chelates heavy metal, and even improves memory (Mishra, 2008, January-March, Abstract, p. 13).

Mizwicki, M. T., Menegaz, D., and Zhang J, et al. (2012). Genomic and nongenomic signaling induced by 1α,25(OH)2-vitamin D3 promotes the recovery of amyloid-β phagocytosis by Alzheimer's disease macrophages. Journal of Alzheimer’s Disease, 29 (1), pp. 51-62. doi: 10.3233/JAD-2012-110560. Evidence Central [Abstract]. Retrieved from http://www.unboundmedicine.com/evidence/ub/citation/22207005/Genomic_and_nongenomic_signaling_induced_by_1%CE%B125_OH_2_vitamin_D3_promotes_the_recovery_of_amyloid_%CE%B2_phagocytosis_by_Alzheimer's_disease_macrophages_

Type 1 Vitamin D3 receptors block amyloid-beta plaque from forming while bisdemethoxy-curcumin (BCC) promotes the engulfing, or phagocytosis, of amyloid beta protein, by type 1 macrophages, or immune cells (Mizwicki, 2012, Abstract, p. 51).

Phagocytosis
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Popular Resources Connecting Vitamin D Deficiency with Alzheimer’s & Dementia

Vitamin D flushes out amyloid-beta plaques from the brain.

Alzheimer’s Prevention. (n. d.). Alzheimer’s Research Center. Retrieved from http://www.alzheimersinfo.org/prevention.html

Vitamin D deficiency is common in older adults because of the skin’s reduced ability to synthesize sunlight into vitamin D. Research associates higher levels of vitamin D with a reduced risk of Alzheimer’s. Older adults may therefore need to supplement their diet with 800 IU of vitamin D daily (as compared to a recommended adult dose of 400 IU), but they should check with their physician first (Alzheimer’s Prevention, n. d., para. 6). However, taking vitamin D supplements is just one of the steps to prevent Alzheimer’s:

Keeping physically active since research shows a link between cardio-respiratory fitness and a healthy hippocampus, the area of the brain responsible for memory (Alzheimer’s Prevention, n. d., para. 1).

Exercising the brain and keeping socially active because this strengthens the links between brain cells (Alzheimer’s Prevention, n. d., para. 2).Eating healthy, unsaturated, un-hydrogenated fats to ensure cardiovascular health as well as including in the diet plenty of green vegetables, like spinach and beans, that are rich in folic acid, and consuming fortified cereals, meat, and liver for vitamin B12 (Alzheimer’s Prevention, n. d., para. 3).

Getting enough vitamin E and C in the diet is important because this reduces the risk Alzheimer’s by controlling the damage produced by free radicals (Alzheimer’s Prevention, n. d., para. 5). Consumers can find Vitamin E in meat, poultry, eggs, fruits, and vegetables, and wheat germ, and they may also take it as a supplement (Vitamin E, 2009, Web M.D., para. 1).
They can also get enough vitamin C by drinking one glass of [red] wine or beer daily whereupon resveratrol will also decrease levels of amyloid plaque (Alzheimer’s Prevention, n. d., para. 6).

In 1992 research showed that resveratrol proved beneficial in preventing coronary heart disease. Subsequent research also indicates that it may be useful in treating and deferring cardiovascular disease, certain cancers, pain, inflammation, tissue injury, and Alzheimer’s disease since it clears amyloid beta peptides and reduces neuron damage. Resverastrol is found not only in grapes, but it is also in berries and peanuts (Li, 2012, Abstract, p. 27).

Note: Resveratrol deserves its own bibliography, so keep checking back to this STEM Library Science blog!

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Anderson, Pamela. (2012, September 12). Low vitamin D linked to Alzheimer’s Disease. Medscape, pp. 1-3. Retrieved from http://www.medscape.com/viewarticle/771782#3

Sufficiently encouraging results exist in longitudinal studies linking lower concentrations of vitamin D to Alzheimer’s to warrant further clinical trials to determine if a cause and effect relationship exists between low concentrations of vitamin D in the blood and the incidence of Alzheimer’s, according to Cynthia Balion, a biochemist at McMaster University in Hamilton, Ontario, Canada. Balion and her colleagues searched Medline, Embase, Amed, PsychINFO, and the Cochrane Central databases for diagnostic criteria and came up with 37 studies showing a link between Alzheimer’s and lower levels of vitamin D, of which 30 included only older participants (Anderson, 2012, September, p. 1).

Although Balion stressed a need for standardized methods of measuring 25OH Vitamin D3, a second meta-analysis revealed that older adults with higher than average Mini-Mental State Examination (MMSE) scores also had higher concentration of vitamin D3 in their blood. This implies that vitamin D acts as a meurosteroid (Anderson, 2012, September, p. 2). Balion therefore advises that physicians should recommend vitamin D supplements for patients who do not have enough vitamin D in their blood, even though results of such blood tests are influenced by latitude, the time of year, and ethnicity (Anderson, 2012, September, p. 3).

Bakalar, Nicholas. (2014, August 14). Vitamin D tied to Alzheimer's risk. Well. New York Times. Retrieved from http://well.blogs.nytimes.com/2014/08/14/vitamin-d-tied-to-alzheimers-risk/?_r=0

A University of Exeter follow-up study that controled for dementia risk factors like age, educational level, gender, BMI, smoking, alcohol use, diabetes, and hypertension in a sample size of 1,658 cognitively and physically healthy men and women with the average age of 73 at the start of the original study found that low levels of vitamin D in the blood increased the risk of Alzheimer's and other types of dementia: Compared with those older adults with 50 or more nanomoles per liter of vitamin D in their blood, those with levels of 25 to 50 nanomoles per liter had a 53 percent increased risk of dementia and a 69 percent increased risk for Alzheimer's while those with readings of 25 or less of vitamin D in a liter of blood were twice as likely to develop Alzheimer's (Bakalar, 2014, August 14, para. 1-3). Senior Lecturer Iain A. Lang at the University of Exeter, however, cautioned that these “exciting and suggestive” results were only “observational” (Bakalar, 2014, August 14, para. 5).

Chan, Amanda L. (2012, March 8). Vitamin D and Alzheimer’s: Study shows how the nutrient can help the brain ward off any amyloid plaques. Healthy Living. Huffington Post. Retrieved from http://www.huffingtonpost.com/2012/03/08/vitamin-d-alzheimers-amyloid-beta-plaque-protein_n_1326952.html

A recent released study shows that vitamin D may clear amyloid plaque by activating certain genes that signal cell networks to “ramp up” the immune system (Chan, 2012, March 8, para. 1 & 2). Taking blood samples from individuals diagnosed with Alzheimer’s and cognitively healthy participants, scientists separated the immune cells responsible for unblocking amyloid beta protein (Chan, 2012, March 8, para. 4). A similar 2009 study found that vitamin D3 coupled with the spice curcumin worked together to unclog amyloid beta plaque while 2010 research demonstrated that lower levels of vitamin coincide with a higher risk of cognitive decline (Chan, 2012, March 8, para. 5-6).

Dockterman, Eliana. (2014, August 7). Low vitamin D increases risk for dementia and Alzheimer’s study says. Time. Retrieved from http://time.com/3089339/study-research-vitamin-d-deficiency-dementia-alzheimers/

Research shows a correlation not a causal link that exists between low levels of vitamin D and Alzheimer’s and other dementias. Nevertheless, a study published August 6, 2014 in Neurology and summarized above hypothesizes that older adults with moderate to severe vitamin D deficiency are “significantly more likely” to develop dementia in (Dockterman, 2014, August 7, para. 1-2 & 4).

This six-year, longitudinal study found that is a sample size of 1,658 Americans age 65 and older, participants who were moderately deficient in vitamin D were 53 percent more likely to be diagnosed with any form of dementia while those severely deficient were 125 percent more likely to develop Alzheimer’s (Dockterman, 2014, August 7 para. 3). The project’s leader, David Llewellyn of the University of Exeter Medical School, emphasized that clinical tests still need to establish whether or eating oily fish or taking vitamin D supplements might best prevent or delay Alzheimer’s and other dementias (Dockterman, 2014, August 7, para. 5).

Doheny Kathleen. (2014, August 11). Low Vitamin D levels may boost Alzheimer's risk. WebMD. Retrieved from http://www.webmd.com/alzheimers/news/20140806/low-vitamin-d-levels-may-boost-alzheimers-risk-study-finds

University of Exeter Medical School researchers correlated dementia with the severity of Vitamin D deficiency when they revisited the U.S. Cardiovascular Health Study of 1,600 adults over age 65 that took place between 1992-1993 and 1999 and compared the blood samples that analyzed Vitamin D content in blood plasma with the participants mental acuity six or more years later. However, the study's findings weren't strong enoung to recommend that older adults take Vitamin D supplements, for their analysis didn't prove a cause and effect link. Thus, researchers as of yet don't know whether upping one's dietary intake of Vitamin D or getting more sun exposure would help (Doheny, 2014, August 11, para. 1-5 & 8). Nevertheless, this comparative study does build on evidence that Vitamin D maintains strong bones, moderates cell growth, controls immune functions, and lessens inflammation (Doheny, 2014, August 11, para. 7).

Researchers discovered that low levels of Vitamin D corresponded with a 1.7 great risk of developing dementia while severely low levels of Vitamin D increased the changes of developing Alzheimer's 2.2 times (Doheny, 2014, August 11, para. 10). While sun exposure provides the body with Vitamin D, it is also found in fatty fish, like salmon, tuna, and mackerel, as well as in milk, eggs, and cheese. Experts nevertheless disagree about the optimal level of Vitamin D in the blood, but they do agree that the risk of dementia significantly increases when it falls below 50 nanometers per liter (Doheny, 2014, August 11, para. 9 & 11).

Fenner, James. (2013, December 4). Vitamin D deficiency linked to brain damage, says study. Guardian Liberty Voice. Retrieved from http://guardianlv.com/2013/12/low-vitamin-d-levels-linked-to-brain-damage-says-study/

Fenner summarizes a collection of studies linking vitamin D deficiency with brain damage, including a contemporize University of Kentucky study published in Freeradical Biology and Medicine (2013, December 4, para. 1). Vitamin D is a fat soluble hormone found in fatty fish, cheese, egg yolks, and fortified mil, and cereal, although the body soaks up most of its store of vitamin D when the sun’s rays strike the skin (Fenner, 2013, December 4, para. 2).

Vitamin D performs multiple functions:

Vitamin D helps the body absorb and maintain calcium levels that build strong bones;
It regulates genes that control cell division and death;
It inhibits inflammation and neuromuscular damage;
It also imparts immunity from various diseases.

(Fenner, 2013, December 4, para. 3)

Additionally, vitamin D may also protect the brain from free radical damage, according to a series of trials wherein researchers administered middle-age male-rats for four-or-five-months low concentrations of vitamin D versus merely adequate and abundant amounts of vitamin D. The rats given the most Vitamin D excelled at cognitive tests while those given a diet deficient in vitamin D didn’t perform as well (Fenner, 2013, December 4, para. 4-8). Poverty, latitudes with little or no sunlight, working indoors for long periods of time, sedentary life styles, and age may all aggravate vitamin D deficiency (Fenner, 2013, December 4, para. 9).

Previous studies have linked vitamin D deficiency, or hypovitaminosis, with a higher incidence of Alzheimer’s, and most recently they have correlated a lower level of vitamin D in the blood of Alzheimer’s patients when compared to their cognitively healthy peers (Fenner, 2013, December 4, para. 10). A 2011 Lu’o’ng and Nguyễn study also found that low levels of Vitamin D could set off “mood problems and cognitive impairment” (Fenner, 2013, December 4, para. 11).

Other studies have established a link between vitamin D deficiency and certain cancers, cardio-vascular conditions, osteoporosis, and rickets (Fenner, 2013, December 4, para. 12) Fenner thus recommends a diet rich in vitamin D and getting at least 10 to 15 minutes of direct sunlight daily. However, patients should consult their physician to check for vitamin D levels and ask him or her about taking supplements (Fenner, 2013, December 4, para. 13).

A link exists between depression, low-levels of vitamin D, and Alzheimer's.

Fischer, Kristen. (2014, August 6). Depression, low vitamin D major risk factors for dementia. Health News. Healthline. Retrieved from http://www.healthline.com/health-news/depression-and-vitamin-d-080614

Two articles published in the August 6, 2014 issue of Neurology have established a connection between a deficiency in vitamin D and Alzheimer’s as well as an association between depression and cognitive decline. However, the study that has received the most publicity, Littlejohns, Henley, and Lang’s, et al, “Vitamin D and the Risk of Dementia and Alzheimer Disease”, which is summarizes above, theorizes that older adults that don’t get enough vitamin D double their risk of Alzheimer’s (Fischer, 2014, August 6, para. 1-2). The leader of this team of researchers, David J. Llewellyn of the University of Exeter explains that the researchers found the association ended up "twice as long as anticipated" (Fischer, 2014, August 6, para. 4).

The leader of this team of researchers, David J. Llewellyn of the University of Exeter, explains, “We expected to find an association between low vitamin D levels and the risk of dementia and Alzheimer's disease, but the results were surprising — we actually found that the association was twice as strong as we anticipated” (Fischer, 2014, August 6, para. 4). Moreover, these results did not vary even when researchers adjusted them for other risk factors, such as smoking, alcohol consumption and level of formal education (Fischer, 2014, August 6, para. 6). Llewellyn, however, cautioned that further studies would need to reveal whether vitamin D supplements or eating foods high in vitatim D would best delay or prevent dementia (Fischer, 2014, August 6, para. 7). He also emphasized that a correlation between low levels of vitamin D with the presence of Alzheimer's does not necessarily prove that a vitamin D deficiency causes cognitive decline (Fischer, 2014, August 6, para. 8).

Osteoporosis is another reason to get enough Vitamin C.

Llewellyn nevertheless acknowledges that past trails have shown that boosting vitamin D has proven effective in treating other health problems; for example, increasing the intake of vitamin D prevents bone fractures. Accordingly, the elderly should eat a balanced diet that includes regularly eating oily fish as well as maintain an active lifestyle, and going outdoors regularly for moderately intensive exercise (Fischer, 2014, August 6, para. 9-10).

In a related Rush University Medical Center study, also published in the August 2014 issue of Neurology, Wilson, Capuano, and Boyle’s, “Clinical-pathologic Study of Depressive Symptoms and Cognitive Decline in Old Age”, researchers showed that the elderly who suffer from depression have a greater risk of developing Alzheimer’s in a study that followed 1,764 volunteers for eight years. Those who were eventually diagnosed with dementia or mild cognitive impairment were more likely to be depressed before their diagnosis of cognitive decline (Fischer, 2014, August 6, para. 11-12).

Consequently, since these findings suggest that depression is a risk factor for dementia, if depression and stress can be prevented or successfully treated, medical science may be able to help the elderly keep their memories and ability to think and reason, according to Rush Alzheimer’s Disease Center neuropsychologist, Robert S. Wilson (Fischer, 2014, August 6, para. 13).

Fischer also provides a hyperlink for the study that connects depression and dementia:

Wilson, R. S., Capuano, Ana W., Boyle, P. A. (2014, July 30). Clinical-pathologic study of depressive symptoms and cognitive decline in old age. Neurology. doi: 10.1212/WNL.0000000000000715. Retrieved from http://www.neurology.org/content/early/2014/07/30/WNL.0000000000000715.short?rss=1

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Glatter, Robert. (2014, August 7). Dementia risk and vitamin D levels: Is there a connection? Forbes. Retrieved from http://www.forbes.com/sites/robertglatter/2014/08/07/dementia-risk-and-vitamin-d-levels-is-there-a-connection/

Vitamin D deficiency may double the risk of cognitive decline and loss of memory, according to a study published online in Neurology on August 6, 2014 (Glatter, 2014, August 7, para. 13). After evaluating levels of vitamin D in the bloodstream of 1,658 healthy adults over age 65, researchers expected to find a link between low levels of vitamin D and the ability to think, remember, and reason, but the association proved twice as strong as they anticipated (Glatter, 2014, August 7, para. 4-5). Vitamin D deficiency may double the risk of cognitive decline and loss of memory, according to a study published online in Neurology on August 6, 2014 (Glatter, 2014, August 7, para. 13).

After evaluating levels of bloodstream in the bloodstream of 1,658 healthy adult volunteers over age 65, researchers expected to find a link between low levels of vitamin D and the ability to think, remember, and reason, but the association proved twice as strong as they had anticipated (Glatter, 2014, August 7, para. 4-5). Thus, individuals with comparatively low levels of vitamin D were 53 percent more likely to develop memory and reasoning problems while those with a “significant deficiency” stood a 125 percent better chance of developing dementia compared to individuals with normal levels of vitamin D (Glatter, 2014, August 7, para. 6).

Indeed, those individuals whose blood contained low levels of vitamin D had a 70 percent greater risk of developing Alzheimer’s while those with the severest deficiency in vitamin D increased their chances of being diagnosed with Alzheimer’s by 120 percent even when researchers controlled for other risk factors (Glatter, 2014, August 7, para. 7-8).

Further clinical trials might establish whether eating oily fish or taking vitamin D supplements might best prevent or delay Alzheimer’s, although the study doesn’t actually show that low levels of vitamin D cause Alzheimer’s or other dementias (Glatter, 2014, August 7, para. 9-10). This means that a multifaceted approach to preventing Alzheimer’s is necessary since diet, lifestyle, and genetic factors might all influence its development. Even so, “good levels of vitamin D” might help prevent the accumulation of amyloid plaque (Glatter, 2014, August 7, para. 11-12).

Two weekly servings of omega 3 fatty fish builds-up vitamin D levels.

Gray, Nathan. (2013, February 12). Omega-3 and vitamin D hay help clear Alzheimer’s plaques. Nutraingredients.com. Retrieved from http://www.nutraingredients.com/Research/Omega-3-and-vitamin-D-may-help-clear-Alzheimer-s-plaques

A pilot study published in the Journal of Alzheimer’s Disease, University of California, Los Angeles, has announced that researchers have discovered the key gene that lies behind vitamin D3 and omega-3’s ability to rid the brain of the amyloid plaque associated with Alzheimer’s, Cyactiv, a blue antioxidant that gives off a “healthy inflammation response” (Gray, 2013, February 12, para. 1-7). Additionally, they have established that individuals with Alzheimer’s have a different inflammatory gene than healthy controls (Gray, 2013, February 12, para. 9).

Drawing blood from both individuals diagnosed with Alzheimer’s and cognitive-healthy older adults, researchers have also isolated critical immune cells, called macrophages, after incubating the immune cells overnight with amyloid-beta and then adding either an active form of vitamin D3 or omega 3 fatty acid whereupon they determined the effect these substances had on inflammation and amyloid-beta absorption. Both vitamin D3 and omega-3 fatty acid improved the ability of the immune cells to break down amyloid beta and inhibit cell death (Gray, 2013, February 12, para. 12-13). These findings might indicate that future Alzheimer’s treatment might need to balance vitamin D supplements and the consumption of omega 3 fatty acid, although a larger sampling size and clinical trials is necessary to confirm these findings (Gray, 2013, February 12, para. 16-18).

Kinkle, Frederick. (2014, August 6). Researchers say vitamin D deficiency raises Alzheimer’s risk. The Washington Post. Retrieved from http://www.washingtonpost.com/national/health-science/researchers-say-vitamin-d-deficiency-raises-alzheimers-risk/2014/08/06/ed278fde-1da1-11e4-82f9-2cd6fa8da5c4_story.html

An international team of researchers led by David J. Llewellyn of the University of Exeter Medical School has determined that adults over age 65 who are evenly moderately deficient in vitamin D stand a 53 percent greater risk of dementia while those with a severe vitamin D deficiency raise their risk of developing Alzheimer’s 125 percent. Furthermore, those found to be moderately deficient in vitamin D are 69 percent more likely to develop Alzheimer’s while those with the lowest levels of vitamin D in their blood are 122 percent more likely to do so (Kinkle, 2014, August 6, para. 2). The risk of dementia rises for levels of vitamin D in the blood below 25 nanomoles per meter while vitamin D levels above 50 nanomoles signify a sufficient level of vitamin D to maintain cognitive health (Kinkle, 2014, August 6, para. 3).

While the researchers acknowledge that dementia might alter behavior or diet in a way that might contribute to vitamin D deficiency, they suggest this is unlikely (Kinkle, 2014, August 6, para. 4). Even so, they admit that further study needs to determine whether consuming oily fish or taking vitamin D supplement might best prevent Alzheimer’s. Research, however, already suggests that vitamin D might regulate calcium levels in brain cells (Kinkle, 2014, August 6, para.5- 6). Vitamin D helps the body use calcium when skin is exposed to sunlight. Experiments also show that vitamin D might help rid brain cells of beta-amyloid plaque, breaking down and carrying it away Kinkle, 2014, August 6, para. 9-10).

Pash, Chris. (2014, August 6). A strong link between vitamin D deficiency and Alzheimer’s risk has been confirmed. Business Insider Australia. Retrieved from http://www.businessinsider.com.au/a-strong-link-between-vitamin-d-deficiency-and-alzheimers-risk-has-been-confirmed-2014-8/

“The most robust study of its kind ever conducted” published in the August 6, 2014 issue of Neurology has documented that older adults who are severely deficient in vitamin D are twice as likely to develop Alzheimer’s and other dementias (Pash, August 6, para. 1-2 & 5). Studying older Americans who took part in the Cardiovascular Health Study, an international team of researchers found that older adults moderately deficient in vitamin D had a 53 percent chance of developing dementia of any kind, but the severely deficient in vitamin D raised their risk 125 percent. Those moderately deficient in vitamin D raised their risk of developing Alzheimer’s 69 percent while those severely deficient in vitamin D had a 122 percent greater risk of eventually being diagnosed with Alzheimer’s (Pash, 2014, August 6, para. 3). Suffering from depression only adds to the risk of developing Alzheimer's since previous researchers have established that individuals with low levels of vitamin D are more likely to develop mental illnesses (Pash, 2014, August 6, para. 13). The exposure of skin to sunlight produces vitamin D, which is also found in oily fish and supplements, but older skin is less efficient than youthful skin in converting sunlight to vitamin D (Pash, 2014, August 6, para. 14-15).

Pederson, Traci. (2012, March 9). Vitamin D explored as Alzheimer’s treatment. Psych Central. Retrieved from http://psychcentral.com/news/2012/03/09/vitamin-d-explored-as-alzheimers-treatment/35774.html

Vitamin D3 may turn on certain genes to jump start the immune system to flush out the amyloid beta plaques that form in the cerebral cortex of Alzheimer’s patients (Pederson, 2012, March 9, para.1-2). Prior research shows that these immune cells respond favorably to vitamin D3 and curcumin, a turmeric spice; however, this particular study clarifies the mechanism involved in this action by taking blood samples from Alzheimer’s patients and healthy controls and then isolating their macrophages, or immune cells, incubating them with amyloid beta amino acids and then introducing an active form of vitamin D3 to see whether it absorbed the amyloid beta peptides (Pederson, 2012, March 9, para. 2 & 4-5).

Apparently, two types of macrophages exist:

Type 1 clears amyloid beta amino acids after researchers introduce a solution of vitamin D3 and curcuminoids, a synthetic form of curcumin.

Type 2 immune cells, however, are found in vitamin D3 alone.

In both types of macrophages, vitamin D3 opens a specific chloride channel (CLC3) that clears out amyloid beta peptides (Pederson 2012, March 9, para. 6-7 & 9). Thus, the vitamin D3 found in Omega 3 fatty fish and in turmeric (or curcumin), which is an ingredient in curry recipes, may help clear out amyloid plaques (Pederson, 2012, March 9, para. 8). Some authorities recommend taking Vitamin D and curcumin together since Vitamin D boosts curcumin's effectiveness.

Turmeric is a common ingredient in curry recipes.

Rodriguez-Paez, Maylin. (2011). Can curry help prevent Alzheimer’s disease? Life Extension. Retrieved from http://blog.lef.org/2014/03/can-curry-help-prevent-alzheimers.html

Indians in their 70s are four times less likely to have Alzheimer’s than their American counterparts are, and curry dishes, made with turmeric (curcumin) may contribute to their mental health (Rodriguez-Paez, 2011, para. 2-5). The curcumin keeps amyloid beta molecules from clumping together and disrupts them once they form. Curcumin, a strong antioxidant, also reduces the amount of free radicals that destroy brain neurons, and it removes heavy metals from the blood stream (Rodriguez-Paez, 2011, para. 10-11).

Turmeric. (2014) Find a vitamin or supplement. Web MD. Retrieved from http://www.webmd.com/vitamins-supplements/ingredientmono-662-TURMERIC.aspx?activeIngredientId=662&activeIngredientName=TURMERIC

Turmeric (curcumin), the primary spice found in curry, is also widely used as an Indian folk remedy to treat a wide variety of ailments since it is thought to decrease swelling or inflammation (WebMD, 2014, para. 1-3 & 7).

Curcumin and its effect on Alzheimer’s deserves its own bibliography entry in the STEM Library Science blog.

See also:

Curcumin: From folk medicine to a possible cure for Alzheimer's. (2015, August 15). Retrieved from http://evelynsmithsstemscienceblog.blogspot.com/2015/08/curcumin-from-fok-medicine-to-possible.html

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Pettersen, J. A. (2015, December 27). Vitamin D and executive functioning. Are higher levels better? Journal of Clinical and Experimental Neuropsychology, pp. 1-11. [E-pub ahead of print]. [Abstract only]. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/26708262

In a study of 142 healthy adults, research found that those with “supra-therapeutic levels” of Vitamin D in their blood performed “significantly better" on verbal fluency tests (Pettersen, 2015, December 27, Abstract, p. 1).

Pettersen, J. A., Fontes, S., and Duke, C. L. (2014, July). The effects of Vitamin D insuficiecy and seasonal decrease in cognition. The Canadian Journal of Neurological Sciences, 41 (4), pp. 459-69. [Abstract only]. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/24878470

After testing the working memory of 32 healthy adults and assessing the levels of Vitamin D in their blood in both the summer and winter, they found that while 46 percent of those with low Vitamin D performed poorly on memory tests in the summer, in the winter, 63 percent had insufficient levels of Vitamin D in their blood, and their memory skills had also declined. Thus, researchers concluded that adults need to maintain their vitamin D levels year round (Pettersen, 2014, July, Abstract, p. 459).

Philip, John. (2013, October 24). Little known form of vitamin D holds key to Alzheimer’s disease prevention. Natural News. Retrieved from http://www.naturalnews.com/042632_vitamin_d3_alzheimers_prevention_prohormone.html#

Researchers are finding that the same lifestyle changes that thwart heart disease also prevent Alzheimer’s (Philip, 2013, October 24, para. 1). In recent years, researchers have verified that turmeric, or curcumin, resveratrol, and omega-3 fatty acids as well as vitamin D “retard or significantly delay” Alzheimer’s (Philip, 2013, October 24, para.2)

In a study published in the November 9, 2012 issue of Current Alzheimer Research, “Low 25OH Vitamin D2 Levels Found in Untreated Alzheimer’s Patients, Compared to Acetylcholinesterase-inhibitor Treated and Controls”, researchers examined blood samples of Alzheimer’s patients and healthy controls and discovered that those diagnosed with Alzheimer’s had low cellular and circulatory stores of vitamin D (Philip, 2013, October 24, para. 3).

Lead researcher Declan Naughton explains that in older adults diagnosed with Alzheimer’s vitamin D was “either nonexistent or in such low qualities that it couldn’t be measured” (Philip, 2013, October 24, para. 4). Medical science has already determined that vitamin D lowers the risk of cancer, cardio-vascular disease, stroke, and diabetes (Philip, 2013, October 24, para. 5).

Simon, Nissa. (2012, July 13). Vitamin D deficiency linked to dementia. AARP Bulletin. Retrieved from http://www.aarp.org/health/conditions-treatments/info-07-2010/vitamin_d_deficiency_linked_to_dementia.html

Senior adults with low levels of vitamin D in their blood are four times more likely to experience cognitive decline as their peers blessed with adequate levels of vitamin D, according to a study led by David Llewellyn, a neuropsychologist at the University of Exeter, who presented their findings at the Alzheimer’s Association International Conference. Llewellyn’s research-team analyzed 3,326 adults age 65 and older and determined that an adverse relationship existed between low levels of vitamin D and impaired thinking skills. Those participants with moderately low levels of vitamin D were 42 percent more likely to perform poorly on memory and mental acuity tests while those blood was “severely deficient” in vitamin D were 400 percent more likely to flunk their Mini-Mental State Examination (Simon, 2012, July 13, para. 3). Most older adults in the United States have low levels of vitamin D in their blood perhaps because the skin becomes less effective in turning sunlight into vitamin D (Simon, 2012, July 13, para. 4-5). Researchers also hypothesize that vitamin D might protect the blood supply to the brain as well as clear toxins, and break down amyloid-beta plaque (Simon, 2012, July 13, para. 6-7).

Soni, M., Kis, K., and Lang, I. A., et al. (2012). Vitamin D and cognitive function. Scandinavian Journal of Clinical and Laboratory Investigation. Supplemetum, 243, pp. 79-82. doi: 10.3109/00365513.2012.681969. [Abstract only]. Retrieved from http://www.ncbi.nlm.nih.gov/pubmed/22536767

Cognitive decline and dementia need to be added to the long list of conditions associated with lower levels of Vitamin D, including osteoporosis, heart disease, stroke, cancer, and type-2 diabetes. Vitamin D receptors are widespread in the brain, and the active form of Vitamin D may clear beta-amyloid plaques. European and United States studies also have associated low levels of Vitamin D with an increased risk of Vitamin D—up to four times greater in severely deficient Vitamin D older adults (Soni, 2012, Abstract, p. 79).

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Natural & Supplemental Sources

of Vitamin D³

Brody, Jane. (2010, July 26). What do you lack? Probably vitamin D. Health. New York Times. Retrieved from http://www.nytimes.com/2010/07/27/health/27brod.html?_r=0

Most Americans are vitamin D deprived, even though every tissue in the body has receptors for the sunshine vitamin. Consequently, vitamin D deficiency raises the risk of colon, breast, and prostate cancer, high blood pressure, cardiovascular disease, osteoarthritis, multiple sclerosis, and rheumatoid arthritis (Brody, 2010, July 26, para. 1-3)—not to mention Alzheimer’s, which Brody does not list in this catalogue of diseases brought on by a modern lifestyle (Brody, 2010, July 26, para. 4). Brody, however, simplifies the process of how sun-exposed skin turns into 25-hydroxyvitamin D³ in the liver and 1,25 vitamin D , or vitamin D hormone, in the kidneys (Brody, 2010, July 26, para. 5). She also suggests that for maximum bone density, the vitamin D³ found in blood samples should reach 40 nanograms per millimeter or more, although mitochondria Eve and Y-chromosomal Adam’s blood probably had 50 nanograms per millimeter. However, not enough sun exposure because of sunscreen and protective covering and perhaps not eating enough fatty fish, like salmon and tuna, ensures that most individuals have lower levels of vitamin D³ (Brody, 2010, July 26, para. 7-9).

Most European Americans average 18 to 22 nanograms of vitamin D³per millimeter of blood while African Americans average between 13 to 15 nanograms of vitamin D³per millimeter of blood (Brody, 2010, July 26, para. 10).

The Northern United States has higher rates of cancer than the South most probably because of reduced sun exposure just as African Americans experience higher rates of high blood pressure, heart disease, and prostate cancer since they have darker skin than white Americans. Similarly, the rise of Type 1 diabetes may stem from overly protecting young children from sun exposure (Brody, 2010, July 26, para. 12).
Current medical practice recommends an intake of at least 200 IU of vitamin D³ daily up to age 50 and 400 I.U. of vitamin D³a day from age 50 to 70, so older adults and pregnant and lactating mothers need to take a vitamin D supplement (Brody, 2010, July 26, para. 14). When the body acquires vitamin D through sunlight, it has a built-in cut off, so it doesn’t absorb too much vitamin D. Individuals really deprived of vitamin D can also stand comparatively high doses (Brody, 2010, July 26, para. 16-18), but it is best to consult a physician before self-medicating.

Lite, Jordan. (2009, March 23). Vitamin D deficiency soars in the U.S., study says. Scientific American. Retrieved from http://www.scientificamerican.com/article/vitamin-d-deficiency-united-states/

According to findings published in JAMA Internal Medicine, 75 percent of all American teens and adults are deficient in vitamin D.

Ginde, A. A., Liu, M. C., & Camargo, C.C. (2009, March 23). Demographic differences and trends of Vitamin D insufficiency in the US population, 1988-2004. JAMA Internal Medicine, 169 (6), pp. 623-632. doi: 10.1001/archinternmed.2008.604. Retrieved from http://www.scientificamerican.com/article/vitamin-d-deficiency-united-states/

Just 23 percent of the blood samples taken in this survey had 30 nanograms per millimeter or more of vitamin D, and only 3 percent of African Americans did so (Ginde, 2009,March 23, para. 2-3). Medical science has long linked vitamin D insufficiency with osteoporosis and rickets, but recent research has determined that it also correlates with heart diseases, diabetes, and cancer (Ginde, 2009, March 23, para. 4). Skeptics, however, in part account for this drop in vitamin D levels by noting that blood tests measure the amount of vitamin D in the blood differently than they use to do (Lite, 2009, March 24, para. 6-7). Even so, Ginde, who insists the study is reliable, blames this drop in vitamin D to an over-reaction to skin cancer campaigns, and he even goes so far as to suggest that African Americans take double the amount of vitamin D supplements recommended for whites (2009, March 23, para. 10).

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Robin, Suzanne. (2014). How to raise your vitamin D3 level. Healthy Eating. SF Gate. Retrieved from http://healthyeating.sfgate.com/raise-vitamin-d3-level-3561.html

The skin synthesizes vitamin Dthat it takes from the sun, but the vitamin is found in lesser amounts in some foods, or it can be taken as a supplement (Robin, 2014, para. 1). Vitamin D², which comes from plants, and vitamin D³ supplements are available, but authorities believe the body absorbs vitamin D³ more efficiently. Spending from 5 to 30 minutes in the sun with the face, arms, legs, or back exposed between 10 A.M. and 3 P.M. in the summer, fall, and winter for just two days a week supplies all the vitamin D most adults need (Robin, 2014, para. 3). The body also stores vitamin D in the liver for 60 days. Nevertheless, the American Academy of Dermatology warns against tanning (Robin, 2014, para. 4).

Beef liver, cheese, egg yolks, and omega-3 fatty fish all contain relatively small amounts of vitamin D³ while mushrooms supply vitamin D². Cod liver oil, however, is the best source of vitamin D other than the sun (Robin, 2014, para. 5). As for supplements, the Food and Nutrition Board recommends a dose of 600 I.U. daily for everyone between one and 70 and a dosage of 800 I.U. daily for adults over age 70 (Robin, 2014, para. 6).

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Vitamin D. Drugs and supplements. (2016). Dosing. Mayo Clinic. Retrieved from http://www.mayoclinic.org/drugs-supplements/vitamin-d/dosing/HRB-20060400

Most multi-vitamins contain from 50 to 100 IU's of Vitamin D. The revised RDA for vitamin D as of 2010 is 600 IU's from age 1 to 70 is 600 IU's, but at age 71 it jumps up to 800 IU's. Even so, an adequate level of vitamin D can be achieved from regular sun exposure on the face, arms, and legs without sunscreen for between 15 to 30 minutes daily (Mayo, 2016, para. 2).

However, to improve cognition, an increase dosage of 528 to 9,000 IU's of Vitamin D2 or Vitamin D3 as been taken daily by mouth from 8 to 40 weeks without harm (Mayo, 2016, para. 9), so older adults with a fading memory and armed with this blog page might wish to ask their physician about the advisablity of upping their Vitamin D supplements. Of course, even though too much sun causes sunburn, the body can't overdose on sun exposure from Vitamin D. Nevertheless, the skin of older adults often has trouble absorbing it.

Vitamin D. Fact sheet for health professionals. (2011 June 24). National Institutes of Health Office of Dietary Supplements. Table 3. Retrieved from http://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/

Selected Food Sources of Vitamin D*

Cod liver oil (1 tablespoon): 1,360 I.U., 340 D.V.
Sockeye salmon (3 ounces): 447 I.U., 112 D.V.
Tuna, canned in water & drained (3 ounces): 154 I.U., 39 D.V.
Orange juice fortified with vitamin D (1 cup): 137 I.U., 34 D.V.
Fortified milk (1 cup): 115-124 I.U., 29-31 D.V
Fortified yogurt (6 ounces): 80 I.U., 20 D.V.
Sardines canned in oil & drained (2 sardines): 46 I.U., 12 D.V.
Beef liver cooked (3 ounces): 42 I.U., 11 D.V.
Egg (1 large): 41 I.U., 10 D.V.
Fortified ready-to-eat cereal: 40 I.U., 10 D.V.
Swiss cheese (1 ounce): 6 I.U. 2 D.V.

*BTW, i have removed margarine and sword fish from this list because of recent medical findings: Medical research has connected the trans fats in margarine to heart disease, and swordfish contains high levels of mercury.

Tozzi, John. (2013, November 7). Twilight of trans fat: The FDA wants to take your margarine away. Bloomsberg Businessweek. Retrieved from http://www.businessweek.com/articles/2013-11-07/twilight-of-trans-fat-the-fda-wants-to-take-your-margarine-away

What you need to know about mercury in fish and shellfish. (2013, November 20). Water: Outreach & Communication. EPA. Retrieved from http://water.epa.gov/scitech/swguidance/fishshellfish/outreach/advice_index.cfm

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Conclusion

Staying physically and mentally active should be everyone's goal.

Taking a brisk 20-minute walk outside after lunch, adding at least two servings of broiled or baked omega-3 fatty fish to the diet weekly, cultivating a taste for curries laced with turmeric (curcumin), and taking vitamin D³ supplements just might prevent or delay Mild Cognitive Impairment and Alzheimer’s. Moreover, since maintaining an adequate supply of vitamin D also guards against the inflammation that causes cardiovascular disease, it certainly will not hurt to take out this form of long-term care insurance!

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Now for a personal note: Since I have written and researched this blog page, I started taking 1,000 mg. of vitamin D daily as well as taking a fish oil supplement that I had stopped taking in the weeks before my mother died this spring. Some time later, I stopped this supplement, although I have continued to eat two servings of omega-3 fatty fish each week. Consequently, I have noticed that my energy level has increased even more than it usually does in the summer months even in the depths of an admittedly mild (compared to most places) Central Texas winter.

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The links furnished on this Web page represent the opinions of their authors, so they complement—not substitute—for a physician’s advice.

STEM Library Science Blog

Sunday, August 10, 2014

Vitamin D May Prevent Alzheimer's & Dementia

A Sampling of Bibliographic Sources on

Vitamin D Deficiency and Dementia

See also:

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