B12 and brain health.

As long as a century ago, researchers discovered that some people, most notably and likely including Mary Todd Lincoln, had a condition called pernicious anemia (PA) that is now-identified as an autoimmune disease. Patients with PA do not produce intrinsic factor (IF), a substance that allows the body to absorb vitamin B12 from foods.

The resulting inadequate levels of vitamin B12 subsequently hampers the production of red blood cells. Mrs. Lincoln was known to behave erratically, demonstrating many strange behaviors that at the time could not be attributed to a then-known disease and with no available treatment was ultimately committed to a mental hospital.

Fast forward to 2020 and we now know that B vitamins are so important for our overall health. A recently published study highlights further the neuroprotective significance of these nutrients and demonstrates the need for clinicians to monitor patient homocysteine levels.

In this animal model of bacterial meningitis (BM) researchers showed that there is insult to the hippocampus, our primary memory center, and elevated levels of homocysteine (Hcy). Homocysteine is an amino acid and breakdown product of protein metabolism that when present in high concentrations has been linked to an increased risk of heart attacks, strokes and impaired brain health. Hcy is also thought to play a role in the neurotoxic damage post-BM as evidenced by the study.

Some of the key takeaways from the research:

1.  Clinical investigations have shown that Hcy (homocysteine) plasma levels are significantly higher in patients with neurologic disorders being a strong independent risk factor relevant to multiple sclerosis, Alzheimer’s disease, and Parkinson’s disease.* Additionally, a tight correlation has been reported between the elevated Hcy plasma levels and cognitive impairment in the elderly. Another study found too that low vitamin B12 levels may be a contributing and potentially modifiable cause of brain volume reduction and subsequent cognitive impairment in the elderly.

2.  Accumulated evidences show that Hcy is a potent neurotoxin, which contributes to oxidative stress in the brain and where it binds and activates N-methyl-D-aspartate (NMDA) receptors.

3. Adjuvant therapy with vitamin B12 modulates the Hcy pathway, increasing global DNA methylation, which may  its neuroprotective effect on the infant rat model of bacterial meningitis by reducing genome instability and modulating the expression of critical genes to the pathophysiology of this disease.

So what can we do to maximize the positive effects?

The link between vitamin B12 and other B vitamins to our brain health is quite clear. Four of my personal top favorite brain supplements to include in addition to a healthy diet are:  

1. B12 is usually given intramuscularly to boost its absorption in people who for many reasons don’t tend to absorb it well otherwise, along with B6 and L-methylfolate (which can be more readily used by our folate enzyme systems vs. folic acid). If using oral B12, methyl B12 is recommended. We want our serum B12 level to be greater than 600.
2.  Choline (Phosphatidyl choline by Thorne®)
3.  Lutein (Mirica® or NeuroProtek®)
4.  Omega 3s (high-quality/95+% pure)

Note: N-Acetyl Cysteine or glutathione has been shown in studies to help lower homocysteine and improve memory in people with cognitive impairment, given in addition to B12, methyl folate and B6 supplements. Ideally we want our homocysteine levels to be less than 7.   

To measure the effectiveness of B12 therapies* we monitor:
1. MCV (mean corpuscular volume) to determine if it has normalized; MCV has been used as screening criteria for B12 deficiency. Macrocytosis, when MCV>100 femtolitres (fl), often precedes anemia that occurs due to defect in red blood cell (RBC) maturation though hemoglobin synthesis proceeds normally. The term macrocytosis refers to a blood condition in which red blood cells (RBC) are larger than normal
2.  Homocysteine is less than 7.  
3.  B12 level is greater than 600 (least reliable indicator).
4.  Normal methylmalonic acid.

It’s important to discuss with us or your primary care physician any supplements or nutraceuticals you may take as needs can vary from one individual to another based on your particular condition or needs. But it does seem clear that B12 and other B-family vitamins can be a positive factor in brain health.

Zivijio (“to a long and healthy life” as my grandmother always said!),
Dr. Suzanne Gazda


Additional references:
American Academy of Neurology. "Vitamin B12 May Protect The Brain In Old Age." ScienceDaily. 11 September 2008.

Kwok, T., Tang, C., Woo, J., Lai, W.K., Law, L.K., Pang, C.P. (1998) “Randomized trial of the effect of supplementation on the cognitive function of older people with subnormal cobalamin levels.” International Journal of Geriatric Psychiatry 13(9):611-6

NeuroProtek: algonot.com/neuroprotek/

Thorne: https://www.thorne.com/

Mirica: https://youngnutra.com/

*Patel S, Dhupar P, Bhattar A (2017). Diagnostic Accuracy of Mean Corpuscular Volume in Delineating Vitamin B12 Deficiency. Annals of Clinical and Laboratory Research. Vol.5:No.3:195. DOI: 10.21767/2386-5180.1000195
https://www.aclr.com.es/clinical-research/diagnostic-accuracy-of-mean-corpuscular-volume-in-delineating-vitamin-b12-deficiency.php?aid=20539#6