Low vitamin B12 level in old people may cause brain atrophy or shrinkage, according to a UK study in Tuesday's Neurology.

This study involved 107 volunteers aged 61 to 87 who were cognitively normal at the beginning of the study, and who underwent annual clinical exams, MRI scans, cognitive tests and had blood samples taken.

Individuals with lower vitamin B12 levels had a greater decrease in brain volume. Those with the lowest levels had a sixfold greater rate of brain volume loss compared with those who had the highest levels of the vitamin.

The researchers write that they were unable to investigate whether lower vitamin B12 could cause cognitive impairment by its effect on brain size.

"Many factors that affect brain health are thought to be out of our control, but this study suggests that simply adjusting our diets to get more vitamin B12 through eating meat, fish, fortified cereals, or milk may be something we can easily adjust to prevent brain shrinkage and so perhaps save our memory," said study author Anna Vogiatzoglou, MSc, with the University of Oxford.

Brain atrophy is associated with Alzheimer's disease and impaired cognitive function, with other risk factors including high blood pressure, diabetes and high cholesterol.

According to the study, vitamin B12 deficiency is a public health problem, especially among older people. And good sources of the vitamin include meat, fish, milk and fortified cereals.

(Xinhua News Agency via Agencies September 9, 2008)