Meeting the minimum requirement for vitamin B12, needed to make DNA, red blood cells and nerve tissue, may not actually be enough – particularly if you are older. It may even put you at risk for cognitive impairment.
A new study, led by UC San Francisco researchers, found that older, healthy volunteers, with lower concentrations of B12, but still in the normal range, showed signs of neurological and cognitive deficiency. These levels were associated with more damage to the brain’s white matter – the nerve fibers that enable communication between areas of the brain – and test scores associated with slower cognitive and visual processing speeds, compared to those with higher B12.
The study published in Annals of Neurology on Feb. 10.
The researchers led by senior author Ari J. Green, MD, of the UCSF Departments of Neurology and Ophthalmology and the Weill Institute for Neurosciences, said that the results raise questions about current B12 requirements and suggest the recommendations need updating.
“Previous studies that defined healthy amounts of B12 may have missed subtle functional manifestations of high or low levels that can affect people without causing overt symptoms,” said Green, noting that clear deficiencies of the vitamin are commonly associated with a type of anemia. “Revisiting the definition of B12 deficiency to incorporate functional biomarkers could lead to earlier intervention and prevention of cognitive decline.”
Lower B12 correlates with slower processing speeds, brain lesions
In the study, researchers enrolled 231 healthy participants without dementia or mild cognitive impairment, whose average age was