Alzheimer's and age-related memory loss could be prevented with a daily dose of Vitamin B, a study has revealed.
Elderly people with mild cognitive impairment (MCI) could halve the rate at which their brain is shrinking by taking a large daily dose of B vitamins, the research shows.
People who suffer from MCI, which leads to dementia and Alzheimer's, see their brain decline much quicker than those without it.
British-led scientists said that the effects of the disease could be slowed down or prevented completely by using the vitamin treatment.
They are now seeking funding for another trial that will put this theory to the test.
The research, published in the online journal Public Library of Science ONE, is controversial because it defies current scientific dogma about the way to tackle Alzheimer's.
It suggests simply taking vitamins can achieve results that have so far evaded pharmaceutical companies, despite millions of pounds being spent on experimental dementia drugs.
Researchers at Oxford University, assisted by colleagues in Norway, used an advanced magnetic resonance imaging (MRI) technique to study brain shrinkage in 168 volunteers over the age of 70 with diagnosed MCI.
Over a period of two years, half were given a daily tablet containing high doses of the B vitamins folate, B6 and B12. The rest received a "dummy" placebo pill with no active ingredients.
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.
On average, taking B vitamins slowed the rate of brain atrophy by 30%, and in some cases reductions as high as 53% were seen.