Researchers from the University of
Oxford have determined that B vitamin supplementation can slow and
possibly reverse the progression of Alzheimer's symptoms along with
cognitive impairment.
The researchers – from Oxford's Nuffield Department of Clinical
Neurosciences - conducted a clinical trial with 156 elderly patients who
had mild cognitive impairment and a high risk of dementia and
Alzheimer's disease.
The researchers randomized the patients and for two years, gave one
group a daily supplement with 800 micrograms of folic acid, 20
milligrams of vitamin B6, and 500 micrograms of
vitamin B12. They gave a placebo supplement to the control group.
Before the trial and during the testing period, the researchers
utilized magnetic resonance imaging (MRI) to measure the patients'
atrophy levels of grey matter in their brains. Atrophying grey matter is
a sign of the progression of Alzheimer's disease and other forms of
dementia. Atrophy in the grey matter is shown as the amount of grey
matter shrinks in the imaging tests.
While grey matter regions did shrink among both groups, the
researchers found that those given the B vitamin supplements had about
seven times less grey matter shrinkage than did the placebo group.
The researchers also found that those whose grey matter shrunk fastest had
higher levels of homocysteine,
and those with higher homocysteine levels received the greatest benefit
from the B vitamin supplements. They summarized the effects thus:
B vitamins lower homocysteine, which directly leads to a decrease in grey matter atrophy, thereby slowing cognitive decline."
The researchers also conducted neuropsychological testing on the
patients to correlate their grey matter losses with neuropsychological
function. Their testing concluded that the B vitamins not only helped
reduce grey matter losses, but also reduced the drop in
neuropsychological scores among the supplement group.
In their conclusion the researchers stated:
Our results show that B-vitamin supplementation can slow
the atrophy of specific brain regions that are a key component of the
Alzheimer disease process and that are associated with cognitive
decline."
Other Studies Confirm the Link Between B Vitamins, Homocysteine and Alzheimer's
However, other studies have linked B vitamins and high homocysteine
levels with cognitive decline, Alzheimer's disease and dementia.
For example, in a study from Korea's Ewha Womans University, 321
elderly people were studied and tested for cognitive function, together
with their levels of vitamin B12, folate and homocysteine.
After using multiple regression analysis, low folate levels were
associated with low scores on naming tests, and low levels of vitamin
B12 in the blood were related to low scores on word list memory. High
homocysteine levels were also associated with low scores on word memory
and construction recall testing.
The researchers stated in their conclusion:
These results suggest that plasma folate, vitamin B12,
homocysteine and tissue factor pathway inhibitor are associated with
cognitive function in cognitively impaired (Alzheimer's disease and Mild
cognitive impairment) elderly and that the association was stronger in
patients with Alzheimer's disease."
What is Homocysteine and why are High Levels so Bad?
Increased homocysteine levels have also been linked with
cardiovascular disease – more specifically the progression of
atherosclerosis or the hardening of the arteries. Thus, high
homocysteine levels have been found among those who have suffered from
strokes and heart attacks.
Elevated homocysteine levels are anything higher than 10-15 μmol/L
depending upon the age and health of the patient. The Oxford researchers
classified their high homocysteine patients as those with levels of 11
μmol.
Homocysteine and its two partners methionine and cysteine, is
involved in the metabolic detoxification process called methylation.
This transfers methyl groups from one molecule to another. When a methyl
group is transferred to a oxidative toxin it speeds its discharge from
the body. Higher levels of homocysteine are typically accompanied by
higher levels of oxidative radicals and toxins in the liver and blood
stream.
If not neutralized, these toxins cause oxidative damage to blood vessels and cells - including brain and nerve cells.
Various nutrients – including B vitamins as well as many other
phytonutrients – are considered methyl donors: They donate methyl
groups, which assists the body's detoxification and healing efforts.
Healthy methylation also helps protect cellular DNA from mutation.
It should also be noted that folate - nature's form - may be a better
form of the B9 vitamin than folic acid. Excessive folic acid
supplementation has been linked with increased cancer risk. A 2009 study
showed folic acid fortification increased colon cancer risk.
Food sources of folate include parsley, turnip and mustard greens,
collard greens, romaine lettuce, spinach, asparagus, broccoli,
cauliflower and beets. Lentils and brewer's yeast are also good sources.
In supplements, the 5-methyltetrahydrofolate (5-MTHF) nutrient offers
an option to synthesized folic acid.
REFERENCES:
Douaud G, Refsum H, de Jager CA, Jacoby R, Nichols TE, Smith SM, Smith AD.
Preventing Alzheimer's disease-related gray matter atrophy by B-vitamin treatment. Proc Natl Acad Sci U S A. 2013 Jun 4;110(23):9523-8.
Morris MS. The role of B vitamins in preventing and treating cognitive impairment and decline. Adv Nutr. 2012 Nov 1;3(6):801-12.
Kim G, Kim H, Kim KN, Son JI, Kim SY, Tamura T, Chang N. Relationship
of cognitive function with B vitamin status, homocysteine, and tissue
factor pathway inhibitor in cognitively impaired elderly: a
cross-sectional survey. J Alzheimers Dis. 2013;33(3):853-62.
Hirsch S, Sanchez H, Albala C, de la Maza MP, Barrera G, Leiva L,
Bunout D. Colon cancer in Chile before and after the start of the flour
fortification program with folic acid. Eur J Gastroenterol Hepatol. 2009
Apr;21(4):436-9.
Pietrzik K, Bailey L, Shane B. Folic acid and
L-5-methyltetrahydrofolate: comparison of clinical pharmacokinetics and
pharmacodynamics. Clin Pharmacokinet. 2010 Aug;49(8):535-48.
Case Adams is
a California Naturopath and holds a Ph.D. in Natural Health Sciences.
His focus is upon science-based natural health solutions. He is the
author of 25 books on natural health and numerous print and internet
articles. A listing and description of many of his books can be found on Realnatural.org. His new video series on low back pain can be found at Healthy-back.net. Case appreciates feedback and questions at case@caseadams.com.
Disclaimer:
This article is not intended to provide medical advice, diagnosis or
treatment. Views expressed here do not necessarily reflect those of
GreenMedInfo or its staff.
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