Low Vitamin B12 Linked to Low Brain Volume

OXFORD, England—A recent study at the University of Oxford found low vitamin B12 status is linked to a decrease in brain volume (Neurology. 2008;71:826-32). The prospective study was conducted over a five-year period on 107 community-dwelling volunteers aged 61 to 87 years without cognitive impairment at enrollment. The decrease in brain volume was greater among those with lower vitamin B12 and holotranscobalamin (holoTC) levels, and higher plasma total homocysteine (tHcy) and (methylmalonic acid) MMA levels at baseline. Associations with vitamin B12 and holoTC remained significant after adjustment for age, sex, creatinine, education, initial brain volume, cognitive test scores, systolic blood pressure, ApoE 4 status, tHcy, and folate. Vitamin B12 in the bottom tertile was associated with an increased rate of brain volume loss. The association was similar for low levels of holoTC and for low transcobalamin (TC) saturation.