Vitamin B12 – Cobalamin overview
Vitamin B12 which is also known as Cobalamin is a member of the vitamin B family of vitamins which is naturally available through some dietary means but can also be taken in supplementary form.
Vitamin B12 is available in several different forms all of which contain cobalt so compounds containing vitamin B12 are referred to collectively as ‘cobalamins’.
Vitamin B12 supplements are generally available in two different forms – cyanocobalamin, which is the most prevalent, and methylcobalamin.
Before we go on to look at the important differences between these two forms of the vitamin, I will take a look at the function and importance of vitamin B12 in general.
Vitamin B12 in General
Vitamin B12 or cobalamin is one of the eight compounds generally referred to as the B-complex vitamins. It is an important vitamin which we need to perform numerous bodily functions.
These functions include the production of red blood cells and energy, synthesizing DNA during the division of cells and helping us maintain good cognitive function especially mood and memory.
Vitamin B12 is absorbed within the small intestines and although vitamin B12 can be gleaned from our diets, it is very poorly absorbed. Even supplementary vitamin B12 is not well absorbed.
The National Institute of Health estimates that only 2% of an oral supplement is actually absorbed into our systems meaning a huge amount of our supplements are being wasted.
Vegetarians and vegans are especially prone to Vitamin B 12 deficiency but it they are not alone. It is also very common among meat eaters mainly because the vitamin is so poorly absorbed in the gut particularly when people are suffering from some sort of intestinal condition. Vitamin B12 deficiency is far more widespread than you might imagine. Studies estimate that around 40% of the population are deficient and the vast majority of those would not even know about it. So with vitamin B12 deficiency being so common, what exactly are the symptoms that may give us a clue?
Symptoms of Vitamin B12 deficiency
With vitamin B12 deficiency being so common, you may not even be aware that you are deficient so it is worth considering whether you have any of the following symptoms:
- Fatigue and weakness
- Chest pain
- Shortness of breath
- Confusion or loss of memory
- A tingling or numbness in your hands or feet
- Discolored, yellowish or pale looking skin
- Poor reflexesA sore tongue or mouth
B12 Deficiency Risk factors
Healthy people should not be at risk of vitamin B12 deficiency although they may need help to absorb it properly. This help to absorb the vitamin comes from a type of glycoprotein which gets excreted from the stomach known as the intrinsic factor.
Most people are able to produce the necessary amount of this intrinsic factor but people with certain illnesses like pernicious anemia or inflammatory stomach conditions may not be able to.
Other risk factors for vitamin B 12 deficiency include alcoholism, vegetarianism, celiac disease and AIDS. People with a MTHFR mutation (C677T and A1298C) are more likely to be B12 deficeint. These people are also less likely to be able to convert Cyanocobalamin into Methylcobalamin.
What is the difference between Methylcobalamin and Cyanocobalamin?
When shopping for a Vitamin B12 supplement whether alone or as part of a multi vitamin supplement, you may be confused by the labels. There are essentially two types of B12 vitamins that you will come across.
Of the two, cyanocobalamin is by far the more commonly used in B12 supplements and multivitamins. However, there is increasing support for it to be replaced by the more natural ingredient – methylcobalamin.
The two different B12 forms are actually very similar and the difference actually comes down to a small molecular part. While methylcobalamin possesses a methyl based group of carbon and hydrogen, cyanocobalamin is bound to a toxic molecule-cyanide.
Cyanocobalamin is not natural; in fact it cannot be found anywhere in nature and is actually created in the laboratory. It is used far more commonly by supplement manufacturers because producers can buy it in bulk at a very low cost especially when compared to the far more expensive alternative – methylcobalamin.
While the amount of cyanide is not thought to be especially toxic or dangerous, it is not something that we necessarily expect to find or would choose to consume when we are shopping for a healthy vitamin product that is supposed to benefit us.
If you are already taking cyanocobalamin there is no real cause for alarm as the levels of cyanide is so low that it is probably not likely to harm you-in fact certain foods like broccoli also contain a very small amount of cyanide. But given the choice, I am sure that most of us would choose to avoid deliberately consuming a known poison.
When you take cyanocobalamin, it gets converted by the body into methylcobalamin which the body needs to function at its best. Given that cyanocobalamin gets converted into methylcobalamin immediately by the body, logic suggest it is also a less efficient method of delivery.
Still, with the cost of methylcobalamin being some 100 hundred times more expensive than methylcobalamin, it is hardly surprising that so many of the lower end manufacturers continue to use it.
According to most experts, the best form of vitamin B12 is the more expensive and natural methylcobalamin. This is actually the form of vitamin B12 which already exists in nature rather than being synthesized in a laboratory. Because it is natural, it is immediately ready to be used by your body and has several advantages compared to cyanocobalamin which include the following.
- It is natural and does not contain any toxic cyanide.
- It is absorbed better by the body.
- It is retained by the tissues better.
- It improves the supply of the body’s methyl donor – S-adenosyl methionine (or SAMe)
- It may improve visual accommodation or the ability to shift focus
Methylcobalamin is also able to outperform cyanocobalamin in several other important ways. There is evidence that when it is taken it stays in a person’s body for considerably longer than its synthetic counterpart. Basically your body should be supplied with vitamin b12 for a longer period if you use methylcobalamin.
If you have a MTHFR gene mutation—it is believed to be the better option (see MTHFR section below).
Methylcobalamin, B 12 Deficiency and Absorption
When it comes to the common matter of vitamin B12 deficiency, the biggest problem for the vast majority of people is not inadequate consumption but the inability to absorb it well enough.
Perhaps one of the most significant benefits of methylcobalamin compared with cyanocobalamin is that there are several ways of taking it that allow the body to absorb it more efficiently so that it can be used as quickly as possible.
Taking methylcobalamin sublingually (placed under your tongue) allows the vitamin to be absorbed more quickly and bypasses the absorption issues that many people may face especially if they have some sort of intestinal problem.
A Conflicting Point of View
Having discussed so much about the superiority of methylcobalamin, I should also go on to say a few words about an opposing viewpoint regarding the best form of vitamin B12 supplement to take.
Vitamin B12 actually has 2 active forms of coenzyme. We have discussed methylcobalamin at length but have yet to mention adenosylcobalamin. When taking cyanocobalamin, it is not only converted into methylcobalamin but also into adenosylcobalamin and there is evidence that while adenosylcobalamin supports energy production in a way that methylcobalamin alone does not.
An article published recently in the European Journal of Clinical Nutrition states that it was more prudent for people to utilize cyanocobalamin rather than methylcobalamin in order to basically get the better of both worlds. (1)
Anecdotal evidence suggests that people absorb cyanocobalamin and methylcobalamin differently. So if you are B12 deficient try both—the one that works better for you may result in a stronger “feel” energy wise. Additionally naturopathic doctors would recommend methylcobalamin with Folate and B6.
Methylcobalamin vs Cyanocobalamin MTHFR
If you have to ask then the following is probably not for you : )
When people talk about B12 and MTHFR, typically it is about a mutation of the MTHFR gene—typically C677T and A1298C. These MTHFR polymorphisms are being studied for things ranging from higher levels of cancers, cardiovascular disease, infertility and arthritis.
Check out this awesome article to find out WAY more about MTHFR and testing options.
Related to B12–If you have one of these mutations, it is likely you cannot properly convert cyanocobalamin to methylcobalamin. For these people it would be much better to take the methylcobalamin form-sublingual being the best option.
There are not any good studies to prove methylcobalamin is superior for those with MTHFR mutations. However, there is tons of anecdotal evidence of people with MTHFR mutations and recommendations from naturopathic doctors who treat MTHFR/B12 deficiency.