Vitamins for Alzheimer's Disease
How can Vitamins help with Alzheimer’s?
By: Dr. Obikoya
Alzheimer's disease is the most common form of dementia.
Approximately 4.5 million Americans have this disease. Although many things
about Alzheimer’s remain a mystery, research continues to bring us a better
understanding of the disease, more accurate diagnoses, and more effective
treatments, particularly the roles of certain vitamins in its prevention.
Alzheimer's disease, first described by the German neurologist Alois Alzheimer,
is a physical disease affecting the brain. During the course of the disease
'plaques' and 'tangles' develop in the structure of the brain, leading to the
death of brain cells.
We also know that people with Alzheimer's have a shortage of some important
chemicals in their brain. These chemicals are involved with the transmission of
messages within the brain. Alzheimer's is a progressive disease, which means
that gradually, over time, more parts of the brain are damaged.
As this happens, the symptoms become more severe. Memory lapses, confusion, mood
swings, and social withdrawal are some of the early symptoms of the disease. As
the disease progresses, people with Alzheimer's will need more support from
those who care for them. Eventually they will need help with all their daily
activities. What causes Alzheimer's disease? So far, no one single factor has
been identified as a cause for Alzheimer's disease. It is likely that a
combination of factors, including age, genetic inheritance, environmental
factors, diet and overall general health, are responsible.
People who have had severe head or whiplash injuries appear to be at increased
risk of developing dementia. Boxers who receive continual blows to the head are
also at risk. Research has also shown that people who smoke and those who have
high blood pressure or high cholesterol levels increase their risk of developing
Alzheimer's. Research findings have long suggested that the antioxidants:
carotenes, vitamin C, vitamin E and other nutrients, might reduce cellular
damage to neurons and protect against dementia.
In 2003, the U.S. National Institute on Aging sponsored a multicenter trial to
test the safety and effectiveness of selected vitamin supplements to treat
Alzheimer's disease. The supplements under investigation are folate, vitamin B6,
and vitamin B12 all previously shown to reduce levels of homocysteine in the
blood.
Studies have shown that high levels of homocysteine, an amino acid that is a
building block of proteins, may be a risk factor for Alzheimer's disease.
Researchers have suggested that the increased level of homocysteines may make
brain cells more vulnerable to the damage that occurs in Alzheimer's disease.
Others studies have linked vitamins C and E to Alzheimer’s disease. Indeed,
recent findings showed that high doses of a combination of these vitamins reduce
the risk of developing Alzheimer’s disease.
Older adults who take supplements containing at least 400 international units of
vitamin E and 500 milligrams of vitamin C may reduce their risk of Alzheimer’s
disease, researchers reported in the January 2004 Archives of Neurology.
However, there was no significant reduction in the risk of Alzheimer's when the
vitamins were taken alone or as part of a multivitamin.
The theoretical basis for the interest in vitamins E and C is their antioxidant
effect. The normal cell function termed “oxidative metabolism” results in
byproducts known as free radicals. Free radicals are highly reactive compounds
that quickly “attack” other cell substances, causing damage to the cell
wall, metabolic machinery, and genetic material (DNA).
The cells have natural defenses against this damage, which include the
antioxidants vitamins C and E, but with age some of these protective mechanisms
decline. Brain cell damage caused by free radicals may play a role in
Alzheimer’s disease
The current recommended daily allowance for vitamin E is 22 international units
or 15 milligrams, and 75 to 90 milligrams of vitamin C, levels that are
typically found in a general-purpose multivitamin. The higher doses most
strongly associated with reduced Alzheimer risk in this study are more often
found in individual supplements.
Genetic research has discovered that the presence of a specific gene variant
called APOE4 is associated with Alzheimer's disease. Those with the APOE4 gene
have lower concentrations of vitamin K in their blood. The data collected thus
far provides evidence that vitamin K may be beneficial in both preventing and
treating Alzheimer's.
One study at the Karolinska Institute in Stockholm, Sweden followed for three
years 370 people who were 75 years or older and had no signs of dementia. During
the study period, the researchers evaluated the participant's blood levels of
vitamin B12 and folate (a.k.a., vitamin B9 or folic acid) and compared them to
normal levels. The results indicate that those patients with below normal levels
of both vitamin B12 and folic acid had twice the risk of developing Alzheimer's
disease than those with normal levels.
There is doubt that there is enough reason for you to start taking your vitamins
if you haven’t already done so. However, you need to consult your doctor on
safety levels or stick with the established Recommended Dietary Allowance (RDA).
Natural dietary sources are okay, but combining a balanced diet with a daily
supplement is often necessary.
References
Archives of Neurology, 2004;61:82-88
Seshadri S, Beiser A, Selhub J, Jacques PF, Rosenberg IH, D'Agostino RB, Wilson
PW, Wolf PA. Plasma homocysteine as a risk factor for dementia and Alzheimer's
disease. N Engl J Med. 2002 Feb 14;346(7):476-83.
Aisen PS, Egelko S, Andrews H, Diaz-Arrastia R, Weiner M, DeCarli C, Jagust W,
Miller JW, Green R, Bell K, Sano M. A pilot study of vitamins to lower plasma
homocysteine levels in Alzheimer disease. Am J Geriatr Psychiatry. 2003
Mar-Apr;11(2):246-9.
Allison A. C. (2001, August). The possible role of vitamin K deficiency in the
pathogenesis of Alzheimer's disease and in augmenting brain damage associated
with cardiovascular disease. Medical Hypotheses, 57(2), 151-155.
Beers, M. H. & Berkow, R. (ed). Dementia [electronic version]. The Merck
Manual of Diagnosis and Therapy, 17th Edition. Merck Research Laboratories, NJ,
1999. Retrieved November 5, 2003, from
www.merck.com/mrkshared/mmanual/section14/chapter171/171c.j sp.
Fauci, A., Braunwald, E., Isselbacher, K., Wilson, J., Martin, J., Kasper, D.,
Hauser, S., Longo, D. (ed). Harrison's Principles of Internal Medicine, 14th
Edition. McGraw-Hill, New York, 1998.
Institute of Medicine of the National Academies. (nd). Dietary reference
intakes: Vitamins. Retrieved November 7, 2003, from
www.iom.edu/includes/dbfile.asp?id=7296.
Maitlin, L. J. (2002, January 14). Vitamin C may improve Alzheimer's treatments.
WebMD Medical News. Retrieved November 5, 2003, from
my.webmd.com/content/article/16/1626_50749.
Mayo Clinic. (2002, May 1). Vitamins and minerals: How much do you need?
Retrieved November 7, 2003, from
www.mayoclinic.com/invoke.cfm?objectid=90B75FDB-D606-494E-81276A8F1 6DB9436.
National Academies Press. (1989). Recommended dietary allowances: 10th edition
[electronic version]. Retrieved November 7, 2003, from
www.nap.edu/books/0309046335/html/.
National Institutes of Health. (2002, June 25). Diet rich in
foods with vitamin E may reduce Alzheimer's disease risk. Retrieved November 7,
2003, from
www.nih.gov/news/pr/jun2002/nia-25.htm.
Wang, H. X., Wahlin, A., Basun, H., Fastbim, J., Winblad, B.
& Fratiglioni, L. (2001, May 8). Vitamin B12 and folate in relation to the
development of Alzheimer's disease. Neurology, 56(9), 1188-1194.