Vitamin B and Alzheimer’s

A simple vitamin pill may be a major development in the treatment of this devastating disease.

New research carried out by scientists at the University of Oxford has found that taking vitamin B tablets reduces the amount by which the brain shrinks as we grow older. The study, (known as VITACOG), is published in the journal Public Library of Science One (PLOS One). The researchers carried out a trial with 168 people aged over 70, with mild memory problems known as Mild Cognitive Impairment (MCI).

The volunteers were split into two groups. The active group received high doses of folic acid, vitamin B12 and vitamin B6. The control group were given a placebo. The volunteers also had Magnetic Resonance Imaging (MRI) scans taken of their brains at the beginning and the end of the two-year trial. By measuring the rate of brain atrophy, or shrinkage, the scientists could see how each participant’s disease had progressed.

Mild Cognitive Impairment is relatively common as we get older – about one in six of the over 70s in this country has MCI, which can involve memory, language and other mental problems. That’s about 1.5 million people.

Alzheimer's

At the MCI stage the changes will be noticeable – so, more than forgetting where you put your keys – but not bad enough to disrupt daily life. Around 50 percent of people with MCI go on to develop Alzheimer’s. Faster brain shrinkage in those with MCI is associated with a progression to Alzheimer’s.

The B vitamins used in the trial are known to control the blood levels of the amino acid homocysteine. High levels of homocysteine are associated with an increased risk of Alzheimer’s.

“This research compared the rate of brain shrinkage between the two groups,” explains Dr Marie Janson, Director of Development at the Alzheimer’s Research Trust, which part-funded the study. “If you’re doing research with psychological testing, there’s always a bit of variation. Being able to look at something as measurable as brain shrinkage on an MRI scan is very solid evidence.”

“With Alzheimers, the disease process goes on for a long time – perhaps 20 or 30 years – before you see noticeable clinical loss of function. In the past we have had to wait for this. Now research is finally getting us the tools we need. With Magnetic Resonance Imaging scans we can now start to pick up shrinkage before the symptoms of Alzheimer’s show.”

At the end of the two year trial, the scientists found that on average, the brains of those taking the vitamin B12, vitamin B6 and folic acid supplement shrank at 0.76 percent a year. In contrast, the brains of those taking the placebo had an average shrinkage rate of 1.08 percent. Those in the active group who had the highest levels of homocysteine in their blood showed the most benefit. Their atrophy rates were half of those in the placebo group.

“It is our hope that this simple and safe treatment will delay the development of Alzheimer’s disease in many people who suffer from mild memory problems,” said Professor David Smith of the Department of Pharmacology, Oxford University, and co-leader of the trial.

“These are immensely promising results but we do need to do more trials to conclude whether these particular B vitamins can slow or prevent development of Alzheimer’s.”

“Taking B vitamins if you have MCI could help to slow it down, so it doesn’t progress as fast,” says Dr Marie Janson. “With a disease that affects this age group, those 70 and over, just postponing it by three or four years can make a huge impact. It’s not just about the number of years you live for, it’s also about the quality of life you have. It’s terribly important.”

If you feel that you or someone you know may have MCI, and might benefit from this treatment, get medical advice first. “I wouldn’t recommend that anybody takes high doses of vitamins on their own, without checking with their GP,” says Dr Janson. “There can be side effects, so you need to talk to your doctor first.”

“This is an interesting study which could change the lives of thousands of people at risk of dementia,” said Professor Clive Ballard, Director of Research at the Alzheimer’s Society. “However, previous studies looking at B vitamins have been very disappointing and we wouldn’t want to raise people’s expectations yet, as we have not specifically seen any benefits in preventing the onset of the symptoms of dementia.”

“This current study from Oxford University measured the rate of shrinkage of the brain and demonstrates the benefit to those starting with high levels of the amino acid homocysteine – a known risk factor for Alzheimer’s Disease. The study doesn’t necessarily show the benefits to people with normal homocysteine levels.

“More research is therefore necessary to show how B vitamin therapy may prevent or delay dementia, particularly in these selected groups of people with higher levels of homocysteine and for those individually at risk of developing Alzheimer’s.

“However, we know that the best way to reduce your risk of dementia is to ensure that you eat a healthy and balanced diet containing fruit and vegetables.”