Brain shrinkage or atrophy is a natural part of ageing but it is known to be accelerated in people with Mild Cognitive Impairment (MCI) – a kind of memory loss and forgetfulness – and Alzheimer's.
Researcher David Smith and colleagues gave 168 volunteers with mild cognitive impairment or MCI 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.
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.
The researchers did not test participants' cognitive ability, but there was an association between brain shrinkage and reduced scores in mental tests.
They said the results were so strong that it should open up a debate as to whether the tablets should be prescribed to everyone with MCI – half of whom develop Alzheimer's disease.
Current research centres around tackling so-called tangles in the brain which are thought to "silt up" the brain's thought processes.
The team at the University of Oxford set out in a new direction – targeting the abnormal physical shrinkage of the brain.
They knew that a substance called homocysteine, an amino acid found in the blood, was associated with this shrinkage.
Elderly people with higher levels of homocysteine, had higher levels of brain shrinkage.
They also knew that vitamin B regulated levels of homocysteine and that the more vitamin B in the blood, the lower the levels of the harmful amino acid.
The researchers used an advanced magnetic resonance imaging (MRI) technique to study brain shrinkage in 168 volunteers over the age of 70 with diagnosed MCI.
At the end of the trial the effects of the vitamin treatment were found to be dramatic, and most pronounced in participants who started out with the highest rates of brain shrinkage.
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.
OTHER DEVELOPMENTS EATING CURRY two or three times a week could help prevent the onset of Alzheimer's and other forms of dementia. The magic ingredient is curcumin, a component of the spice turmeric. Curcumin prevents the spread of harmful amyloid plaques found in the brain of Alzheimer's sufferers.