Mild vitamin B12 deficiency associated with accelerated cognitive decline, study finds

(Medical Xpress)—Being mildly vitamin B-12 deficient could be an indication that some older adults are at a greater risk for accelerated cognitive decline, an observational study from researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging (USDA HNRCA) at Tufts University suggests.

Martha Savaria Morris, Ph.D., an in the Nutrition Epidemiology Program at the HNRCA at Tufts University, and colleagues examined data from 549 men and women enrolled in a cohort of the , focusing on scores on the Mini-Mental State Examination (MMSE), 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 .

Being in the two lowest groups was associated with significantly accelerated cognitive decline, based on an analysis of test scores from 5 MMSE tests given over a period of eight years. The average age at baseline was 75 years-old.

"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 of low vitamin B-12 status may affect a much larger proportion of seniors than previously thought."

In the August 2012 issue of the , Morris and colleagues write that MMSE scores dropped, on average, 0.24 points per year versus an average drop of 0.35 points annually in the two groups with the lowest vitamin B-12 blood levels. The authors observed an even steeper decline of about 1-point per year in some people in the two lowest groups who also exhibited high blood levels of or took supplements containing its synthetic form, folic acid, although their models indicate the additional cognitive decline is potentially related to other health problems in this particular study population.

The subjects in this study were mostly Caucasian women who had earned at least a high school diploma. The authors said future research might include more diverse populations and explore whether vitamin B12 status impacts particular cognitive skills, as the MMSE results provide only a general picture of decline.

"While we emphasize our study does not show causation, our associations raise the concern that some may be the result of inadequate vitamin B-12 in , for whom maintaining normal blood levels can be a challenge," said Paul Jacques, D.Sc., the study's senior author and director of the Nutrition Epidemiology Program.

Animal proteins, such as lean meats, poultry and eggs, are good sources of vitamin B-12. Because older adults may have a hard time absorbing vitamin B-12 from food, the USDA's 2010 Dietary Guidelines for Americans recommend that people over 50 years-old incorporate B-12 fortified foods or supplements in their diets.

Jacob Selhub, Ph.D., director of the Vitamin Metabolism Laboratory at the USDA HNRCA, co-authored the study. Selhub and Jacques are also professors at the Friedman School of Nutrition Science and Policy at Tufts University.

More information: Morris MS, Selhub J and Jacques PF. "Vitamin B-12 and Folate Status in Relation to Decline in Scores on the Mini-Mental State Examination in the Framingham Heart Study." Journal of the American Geriatrics Society. 60:1457-1464, August 2012.

add to favorites email to friend print save as pdf

Related Stories

Vitamin B-12 function may be diminished by excessive folate

Dec 18, 2007

In a study of adults aged 20 and over, researchers at Tufts University showed that homocysteine and methylmalonic acid are at much higher levels in individuals who have a combination of vitamin B12 deficiency and high blood ...

Folate and B12 may influence cognition in seniors

Feb 09, 2007

Folate and vitamin B12, two important nutrients for the development of healthy nerves and blood cells, may work together to protect cognitive function among seniors, reports a new epidemiological study from the Jean Mayer ...

Vitamin D tied to women's cognitive performance

Nov 30, 2012

Two new studies appearing in the Journals of Gerontology Series A: Biological Sciences and Medical Sciences show that vitamin D may be a vital component for the cognitive health of women as they age. ...

Recommended for you

Testosterone testing has increased in recent years

Nov 21, 2014

(HealthDay)—There has been a recent increase in the rate of testosterone testing, with more testing seen in men with comorbidities associated with hypogonadism, according to research published online Nov. ...

AMA: Hospital staff should consider impact of CMS rule

Nov 21, 2014

(HealthDay)—Hospital medical staff members need to consider the impact of a final rule issued by the Centers for Medicare & Medicaid Services (CMS) that revised the conditions of participation for hospitals ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.