foodconsumer.org: B vitamins prevent dementia

B vitamins prevent dementia
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admin on 09/09/2010 01:50:00
 
Good news for people with mild cognitive impairment.  Taking daily supplements
of B vitamins may delay the onset of dementia like Alzheimer's disease, a study
led by researchers at Oxford University suggests.   Researcher David Smith and
colleagues gave 168 volunteers with mild cognitive impairment a vitamin pill
called "TrioBe PPLus" containing 300 times the recommended daily dose of B12,
four times daily recommended amount of folate and 15 times the recommended dose
of B6 for two years.   Participants' brains were scanned at the beginning and
the end end of the trial to monitor the brain shrinkage or atrophy.   The study
published in the Public Library of Science (PLoS) One journal showed that on
average the brain shrinkage in those who took the B vitamins was 0.76 percent a
year compared to 1.08 percent for those who took the placebo.   Researchers did
not test participants' cognitive ability or symptoms of dementia, but there was
an association between brain shrinkage and reduced scores in mental tests.  
Brain shrinkage is a natural phenominum found in elderly people.  Drinking
alcohol can hasten the process, but it is unknown if B vitamins may offset the
negative effect of drinking alcohol.   Mary N. Haan of the University of
California-San Fransisco recently found that lower levels of folate were
associated with symptoms of dementia and poor brain function or cognitive
decline.   Low doses of B vitamins may not help.   One study, led by van Uffelen
J.G. and colleagues from TNO-VU University Medical Center in The Netherlands,
found a vitamin supplement containing 5 mg folic acid, 0.4 mg vitamin B12 and 50
mg vitamin B6 did not help people with mild cognitive impairment.   In the
study, 77 patients with mild cognitive impairment took the vitamin supplement
and 75 patients engaged in a low-intensity walking program for 12 months.  All
patients were evaluated at the begining and the end of the study.   Researchers
reported in the May 2008 issue of British Journal of Sports Medicine that
neither walking nor the vitamin supplement could curb the progression of
cognitive decline, however the walking program was effective in improving memory
in men, and memory and attention in women.   Dementia is a term for a group of
symptoms caused by brain disorders. People with dementia may not be able to
think well enough to conduct normal activities likely getting dressed and
eating. People with mild cognitive impairment may or may not develop dementia.  
Memory loss is a common symptom of dementia, but a person with memory loss alone
may not neccessarily suffer dementia, which can include Alzheimer's disease and
stroke.   It should be noted that the current study used mega-dosages of B
vitamins, meaning that they should be considered drugs but not dietary
supplements. High doses of B vitamins can be risky.   Vitamin B12 is essential
for vegans as this nutrient cannot be found in plant-based foods. Lack of
vitamin B12 can lead to cognitive problems like mild cognitive impairment .   By
David Liu,  editing by Laura Lamp King