Vitamin B-12 May Help Maintain Brain Size

by | Sep 17, 2008 | 2008, Brain Health, Cognitive Health, Vitamin B12 - Mental

Written by Greg Arnold, DC, CSCS. Compared to those with the highest blood levels of B-12, those with the lowest levels had 3 times the risk of decreased brain volume.

Alzheimer Disease (AD) has doubled among Americans since 1980, currently affecting more than 4.5 million Americans, and expected to affect16 million by 2050 (1). The condition costs $100 billion each year to treat (2). As with any chronic disease, there is a gradual deterioration of the body’s processes before physical manifestations of AD occur and may be present years before it can be diagnosed (3) Brain atrophy (4) is now an established marker of AD progression (5).

A recent study (6) has found that vitamin B12 may benefit brain health by playing a role in helping preserve brain size.

In the study, 107 volunteers with an average age of 73 years and no cognitive impairment provided blood samples to measure for plasma vitamin B12, two proteins that transport B12 in the blood called transcobalamin (TC), holotranscobalamin (holoTC), MMA (a measure of cell damage and aging (7)), homocysteine (an independent risk factor for AD (8) and cognitive decline (9)), and folic acid. The volunteers also completed cognitive testing (called the CAMCOG (10)) and underwent MRI scans to measure brain volume (11).

The researchers found that, compared to those with the highest blood levels of vitamin B12 (greater than 386 picomoles per Liter), those with the lowest blood levels of B12 (less than 308 picomoles per Liter) had a 300% increased risk of having a decrease in brain volume. This risk increased to 600% when the researchers also accounted for creatine levels (a breakdown product of muscle that also measures kidney health (12), years of further education, CAMCOG scores, and systolic blood pressure. No associations were seen between homocysteine levels and brain volume.

For the researchers, “Low vitamin B12 status should be further investigated as a modifiable cause of brain atrophy and of likely subsequent cognitive impairment in the elderly.”

Source: Vogiatzoglou, A., H. Refsum, Carole Johnston, S. M. Smith, K. M. Bradley, C. De Jager, M. M. Budge, and A. D. Smith. “Vitamin B12 status and rate of brain volume loss in community-dwelling elderly.” Neurology 71, no. 11 (2008): 826-832.

© 2008 AAN Enterprises Inc.

Posted September 17, 2008.

References:

  1. Hebert, LE; Scherr, PA; Bienias, JL; Bennett, DA; Evans, DA. “Alzheimer Disease in the U.S. Population: Prevalence Estimates Using the 2000 Census.” Archives of Neurology August 2003; 60 (8): 1119 – 1122.
  2. Ernst, RL; Hay, JW. “The U.S. Economic and Social Costs of Alzheimer’s Disease Revisited.” American Journal of Public Health 1994; 84(8): 1261 – 1264.
  3. Smith AD. Imaging the progression of Alzheimer pathology through the brain. Proc Natl Acad Sci USA 2002;99:4135–4137.
  4. Jobst KA, Smith AD, Szatmari M, et al. Detection in life of confirmed Alzheimer’s disease using a simple measurement of medial temporal lobe atrophy by computed tomography. Lancet 1992;340:1179–1183.
  5. Bradley KM, Bydder GM, Budge MM, et al. Serial brain MRI at 3-6 month intervals as a surrogate marker for Alzheimer’s disease. Br J Radiol 2002;75:506–513.
  6. Vogiatzoglou A.  Vitamin B12 status and rate of brain volume loss in community-dwelling elderly.  Neurology 2008 Sep 9;71(11):826-32.
  7. “Methylmalonic acid test” posted on the Med Line Plus website.
  8. Clarke R, Smith AD, Jobst KA, et al. Folate, vitamin B12, and serum total homocysteine levels in confirmed Alzheimer disease. Arch Neurol 1998;55:1449–1455.
  9. Tucker KL, Qiao N, Scott T, et al. High homocysteine and low B vitamins predict cognitive decline in aging men: the Veterans Affairs Normative Aging Study. Am J Clin Nutr.
  10. Tsolaki M.  The Cambridge Cognitive Examination (CAMCOG): A validation study in outpatients suffering from dementia and non-demented elderly subjects (including Age Associated Cognitive Decline patients) in Greece American Journal of Alzheimer’s Disease and Other Dementias®, Vol. 15, No. 5, 269-276 (2000).
  11. Smith SM, Zhang Y, Jenkinson M, et al. Accurate, robust, and automated longitudinal and cross-sectional brain change analysis. Neuroimage 2002;17:479–489.
  12. “Creatinine” posted on the Med Line Plus website.