Vitamin B12 and Your Brain
©Arlene R. Taylor PhD www.arlenetaylor.org
“I’m struggling with a fuzzy memory,” Jessie told the doctor. “At times I feel confused, can’t recall details well, and fear I’m heading down the path toward dementia!”
“You may be experiencing low levels of Vitamin B12 or cobalamin,” the doctor replied. “A number of symptoms are associated with lower-than-desirable levels.”
Sure enough, a simple blood test showed that Jessie’s levels of B12 were low. Not even a real deficiency according to published ranges, mind you. Just low levels within the normal range. But low enough for Jessie to have produced symptoms of confusion and memory delays. Serious B12 deficiencies, on the other hand, have been associated with everything from severe damage to the brain and nervous system to symptoms of mania and psychosis.
“By increasing your intake of absorbable B12,” said the doctor, you may be able to modify your risk for memory and cognitive decline.”
The next thing Jessie wanted to know was whether one could take too much B12.
“There is good news,” said the doctor, “Vitamin B12 has extremely low toxicity and even taking it in enormous doses appears not to be harmful to healthy individuals.”
This water soluble vitamin is vitally important to the healthy functioning of the brain and nervous system. That’s likely one reason that, along with vitamin B6, it is referred to as the brain vitamin. Of course, it plays a key role in other bodily functions, too. In the formation of blood, in the metabolism of every cell, and in the synthesis of DNA and fatty acids. Vitamin B12 is touted to be the largest and most structurally complicated vitamin currently known.
Recent studies have shown that up to 40% of the population may have B12 levels that range from low to shockingly low. Perhaps even more frightening, a B12 deficiency can contribute to brain shrinkage, a condition associated with decreased brain function. According to a University of Oxford study, research is linking B12 deficiency with, among other negative consequences, Alzheimer’s disease. The Oxford two-year randomized clinical trial is the largest to study the effect of B vitamins on mild cognitive impairment, and one of the first disease-modifying trials in the Alzheimer’s field to show positive results in humans.
Simple, you say. Just up your intake of Vitamin B12. Turns out that this may not be a simple as you may think. For example, some individuals have been taking B12 in a commonly available form known as cyanocobalamin. Ouch! It’s a derivative of cyanide (think Agatha Christie murders).
According to Wikipedia, in the body this common synthetic form of cyanocobalamin is converted to the physiological forms methylcobalamin and adenosylcobalmin, leaving behind cyanide. Yes, you read it correctly. A small concentration of cyanide, but cyanide nonetheless. Check the ingredient list for cyanocobalamin. If you see it listed, you may want to run—not walk—the other way. What are manufacturers thinking? No doubt that it is 100 times cheaper than the more desirable form: methylcobalamin.
So what can you do?
If you eat meats and yogurt, they can be sources, although due to common intestinal ailments any are unable to absorb vitamin B12 from their intestines. Patches that deliver B12 are available; as are injections of B12 and sublingual forms.
Selected References
http://news.bbc.co.uk/2/hi/health/7595423.stm
http://www.alzheimersweekly.com/content/folic-acid-b6-b12-slows-memory-decline
http://en.wikipedia.org/wiki/Vitamin_B12
http://ods.od.nih.gov/factsheets/vitaminb12/