Study: Inadequate vitamin B12 in seniors could be linked to cognitive decline

BOSTON — Being mildly vitamin B-12 deficient could be an indication that some older adults are at a greater risk for accelerated cognitive decline, according to an observational study from researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University released Wednesday.

Lead researcher Martha Savaria Morris of the Nutrition Epidemiology Program at the HNRCA examined data from 549 men and women enrolled in a cohort of the Framingham Heart Study, focusing on scores on the Mini-Mental State Examination, a short list of questions and tasks commonly used to screen for dementia. The subjects were divided into five groups, based on their vitamin B-12 blood levels.

Being in the two lowest groups was associated with significantly accelerated cognitive decline, based on an analysis of test scores from five MMSE tests given over a period of eight years. 

“Men and women in the second lowest group did not fare any better in terms of cognitive decline than those with the worst vitamin B-12 blood levels. Over time, their MMSE scores declined just as rapidly,” Morris said. “Rapid neuropsychiatric decline is a well-known consequence of severe vitamin B-12 deficiency, but our findings suggest that adverse cognitive effects of low vitamin B-12 status may affect a much larger proportion of seniors than previously thought.”

“While we emphasize our study does not show causation, our associations raise the concern that some cognitive decline may be the result of inadequate vitamin B-12 in older adults, for whom maintaining normal blood levels can be a challenge,” stated Paul Jacques, the study’s senior author and director of the Nutrition Epidemiology Program.