B vitamins play a critical role in the maintenance of vital and balanced health. They facilitate a wide variety of indispensable processes throughout the body, including red blood cell formation, energy production and metabolism, nervous system function, and a number of different defense and detoxification mechanisms.
Vitamin B12 is especially important, and thus a chronic deficiency in it can lead to more serious health consequences than nearly any other deficiency. While the range of deleterious effects that can result from B12 deficiency is wide and voluminous, one area where it hits hardest is neurological health.
This is because vitamin B12 is invaluable for the development and optimal function of brain and nerve cells. Without it, a frightening set of symptoms and ailments can set in: what begins as fatigue, slight neuropathy (tingling in the extremities), and low-level mood imbalances can escalate to dementia and other expressions of advanced neurodegeneration, severe psychiatric disorders, and degeneration of the spinal cord (which can lead to visual problems (including blindness), bladder dysfunction, erectile dysfunction, cardiovascular issues, and gastrointestinal issues).[1]
Let’s take a look at how vitamin B12 helps safeguard the brain and nervous system against all of these nasty health situations.
How B12 protects brain health
A growing body of research demonstrates that vitamin B12 is intimately linked with the health of myelin, the fatty sheath that protects brain and nerve cells against stress and damage, and also aids nerve-impulse communication between cells.
Vitamin B12 not only helps to protect the integrity of myelin, but also is central to its synthesis. Here’s how it works: myelin, as well as many other critical compounds (including DNA, RNA, serotonin, dopamine, acetylcholine, and norepinephrine), are synthesized in large part because of a process called the one-carbon metabolism cycle.
This incredibly complex process, which ultimately involves a cascade of chemical reactions throughout every cell in the body, simply cannot happen without vitamin B12. This is because B12 is a co-factor for the synthesis of methionine, an amino acid that jumpstarts the synthesis of all the compounds mentioned above. Similarly, B12 is also necessary for the synthesis of succinyl CoA, a compound that keeps myelin stabilized.
Without vitamin B12, brain degeneration occurs for a number of reasons. Without the ability to synthesize myelin, the body can’t effectively protect brain and nerve cells against damage.
Furthermore, methionine is synthesized from homocysteine, a harmful amino acid that can wreak havoc on the brain if allowed to accumulate. In fact, one study reported that one in every six cases of dementia is directly attributable to high homocysteine levels.[2] When B12 levels are optimal, homocysteine is used to synthesize methionine, and any excess is detoxed from the body. In the case of a B12 deficiency, though, this cycle breaks down, and accumulating homocysteine precipitates neurodegeneration.[3]
In like manner, succinyl CoA is metabolized from methylmelonyl CoA—if this precursor doesn’t have B12 to enable its conversion into succinyl CoA, it is instead metabolized into methylmalonic acid (MMA), a harmful chemical that leads to unstable myelin and even the breakdown of existing myelin (this process is known as “demyelination”).[4]
In short, many of the complex processes required for optimal brain health grind to a halt without proper levels of vitamin B12. Because so many people are deficient in vitamin B12 (up to 40% of the American population, with another 39% hovering right above deficiency), it’s no surprise then that the incidence of neurological disease is skyrocketing.
And the neurological consequences of B12 deficiency are not limited to the elderly (the age group more predisposed to Alzheimer’s and other signs of neurodegeneration). Researchers have found that B12 deficiency is just as detrimental (if not more so) for children.
According to a study published in Pediatric Emergency Care, children exhibiting B12 deficiency display symptoms such as lethargy, failure to thrive, hypotonia (a condition characterized by weak muscle tone and coordination, and which is therefore also called “floppy baby syndrome”), and the halting or even regression of physical and psychological development. Worst of all, if left untreated, B12 deficiency can lead to permanent neurological disabilities.[5]
But all of these consequences are easily averted
Here’s the good news: studies have demonstrated that vitamin B12 supplementation very quickly attenuates the symptoms and conditions discussed above.
There’s only a few guidelines you’ll need to follow in order to ensure best results. Vitamin B12 is somewhat difficult for your body to absorb, which is why B12 injections are common in clinical settings (as opposed to oral supplements).
However, research shows that the bioavailability of liposomal vitamin B12 is on par with B12 injections—and it’s far more affordable. The absorbability and efficacy of sublingual B12 has never been demonstrated, so beware of most store-bought products.
Lastly, always make sure that the product you choose is made from methylcobalamin, the most potent and highest-quality form of vitamin B12.
References
[1] http://emedicine.medscape.com/article/1152670-clinical
[2] http://ajcn.nutrition.org/content/85/2/329.full
[3] http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0147843
[4] Ibid.