B vitamins may slow onset of Alzheimer's

摘要

Those at risk of developing Alzheimer's may be able to slow its onset, through daily B vitamins. We already know that a high level of the amino acid homocysteine in the blood is a risk factor for Alzheimer's, and that B vitamin supplements help reduce homocysteine levels. But it was unclear whether or not these supplements could slow the progression of mild cognitive impairment (MCI) to Alzheimer's. David Smith and Gwenaeelle Douaud at the University of Oxford led a research effort to find out. They used MRI to track changes in the brains of 200 elderly volunteers with MCI over two years. Half were given high doses of vitamin B12, B6 and folic acid - the rest took a placebo. The team found that areas of the brain most seriously affected by Alzheimer's, including the hippocampus and cerebellum, were protected in volunteers given the vitamins. For instance, in those with high homocysteine, the atrophy rate in these brain regions was seven times greater in the placebo group than in the vitamin group.