B12 and Brain Shrinkage

A study was reported earlier this week that found an association between B12 deficiency and brain shrinkage. Time had a write-up: Low Vitamin B12 Linked to Smaller Brains and Cognitive Decline.

It inspired me to create a separate page on VeganHealth.org, Mild B12 Deficiency – Dementia & Depression. Most of that information used to reside at Mild B12 Deficiency – Elevated Homocysteine, but I decided that it is important enough to warrant its own page.

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The paper is a report from the Chicago Health and Aging Project. Rather than trying to describe their methods and statistical analysis in detail, I will simply copy two important paragraphs from the paper that summarize their findings:

“Thus, our findings lend support for the contention that poor vitamin B12 status is a risk factor for brain atrophy and possibly WMHV [white matter hyperintensity volume] which in turn may contribute to cognitive impairment.”

“Marginal vitamin B12 status in older age is frequently missed by measurement of serum vitamin B12 levels alone. Our findings suggest that [methylmalonic acid], the specific marker of B12 deficiency, may affect cognition by reducing [total brain volume] whereas the effect of homocysteine on cognition may be [caused by] increased WMHV and [strokes].”

In other words, long-term moderate vitamin B12 deficiency is not good for the brain.


1. Tangney CC, Aggarwal NT, Li H, Wilson RS, Decarli C, Evans DA, Morris MC. Vitamin B12, cognition, and brain MRI measures: A cross-sectional examination. Neurology. 2011 Sep 27;77(13):1276-82. Link

One Response to “B12 and Brain Shrinkage”

  1. VeganMoFo 9: Vegan news you can use (B12!) and the weekly-round up (10/9/11) Says:

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