The study, published in the journal Public Library of Science One, suggests dietary supplementation of B vitamins could reduce levels of plasma homocysteine, leading to reduced brain atrophy and slower development of dementia.
The researchers claim their findings could be the first step towards finding a way to delay the onset of Alzheimer's.
“We have shown that treatment for two years with B vitamins markedly slows the accelerated rate of atrophy in people with MCI,” wrote the authors, led by Prof David Smith of the University of Oxford.
Wasting in the brain, or atrophy, is a common symptom of mild cognitive impairment (MCI), and can be an early warning to signs of dementia.
One important factor determining the rate of atrophy appears to be raised concentrations of the amino acid homocysteine.
Previously, epidemiological studies have reported that high levels of homocysteine are associated with suspected or confirmed dementia. Indeed, the Framingham study reported that people with homocysteine levels above 14 micromoles per litre of serum had twice the risk of dementia.
Tissue and plasma concentrations of homocysteine are known to be determined by vitamin B status, as they are cofactors for enzymes involved in homocysteine metabolism.
The new study investigated the links between vitamin B supplementation and lower levels of plasma homocysteine.
The study followed 168 participants over two years, finding that those taking vitamin supplements had on average 30 percent less brain shrinkage, however the study reported some patients showed more then a 50 percent reduction.
“B vitamin treatment led to a difference in final homocysteine concentration of 31.7 percent compared with the placebo, and was accompanied by a reduction in the rate of brain atrophy of almost 30 percent,” wrote the researchers.
The authors concluded that an accelerated rate of brain atrophy in elderly people with mild cognitive impairment could be slowed via dietary supplementation with homocysteine-lowering B vitamins.
The authors state that “the importance of these findings will be in relation to future trials,” noting that further trials are needed to test the methods on the development of Alzheimer’s disease.
“The important issue is that people with high homocystine levels show strong improvements”, said Dr. J. Wesson Ashford, Senior Research Scientist at the Stanford/VA Alzheimer’s Center.
Speaking to NutraIngredients-USA.com, Dr Ashford noted that vitamin B deficiency can lead to high levels of homocystine – something that could be a common but preventable cause of MCI and dementia.
Ashford stated that prevention of vitamin B deficiency through supplementation could help to reduce the development of dementia.
“You have to ask yourself is it cost effective to take a daily supplement that could reduce the risks of certain diseases.”
“Most of the time half of these vitamins and supplements go right through you, because you don’t need them, but they can make up for vitamins you are lacking in, reducing the risks of serious deficiencies - For ten bucks a year to buy some multivitamins – I suspect it’s worth it,” he added.
Source: Public Library of Science One
Published online ahead of print, doi: 10.1371/journal.pone.0012244
“Homocysteine-Lowering by B Vitamins Slows the Rate of Accelerated Brain Atrophy in Mild Cognitive Impairment: A Randomized Controlled Trial”
Authors: A. David Smith, S.M. Smith, C.A. de Jager, P. Whitbread, C. Johnston, G. Agacinski, A. Oulhaj, K.M. Bradley, R. Jacoby, H. Refsum