Are You Taking the Right Form of B12?

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The Pure TheraPro Team

The Pure TheraPro Education Team is comprised of researchers from diverse backgrounds including nutrition, functional medicine, fitness, supplement formulation & food science. All articles have been reviewed for content, accuracy, and compliance by a holistic integrative nutritionist certified by an accredited institution.
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Optimal B12 levels are important to your health. Vitamin B12 protects both DNA and RNA, provides you with energy, protects your nerve and brain cells, helps regulate serotonin levels, assists with red blood cell formation, supports your immune system and helps regulate your mood. Many with low levels of B12 suffer from depression and anxiety, insomnia, poor immune function, gut issues, brain fog, neuropathy, cardiovascular issues, chronic fatigue and more.

Vitamin B12 and folate work together in the body on many of these functions, such as helping balance homocysteine levels. Both nutrients assist with synthesizing melatonin, allowing you to get a good night’s sleep.

B12 converts homocysteine to methionine, which reduces the possibility of damage to various systems, due to increasing levels of the master anti-oxidant, glutathione. Glutathione helps detoxify the body and protect cells from damage.

High homocysteine levels may contribute to atherosclerosis and increased vascular demands, making it a key indicator of heart disease and stroke risk as well as other chronic diseases.

B12 and folate work together to provide benefits for cognitive health, as well. A study by Morris et-al found that the combination of low B12 and high Folate levels led to cognitive decline; High levels of B12 AND Folate were protective against cognitive decline.

Keep in mind, however, that not all vitamin B12 supplements are created equally. There are four forms of B12; the two main ones are: cyanocobalamin and methylcobalamin.

What’s the difference between Cyanocobalamin and Methylcobalamin?

Structurally, each have a different molecule attached to the cobalt ion. While methylcobalamin contains a methyl group, cyanocobalamin contains a cyanide molecule.

Cyanocobalamin is a synthetic form not found in nature.

Methylcobalamin is in its natural form.

When taking Cyanocobalamin, your liver must remove the cyanide molecule and attach a methyl group to create the active form, methylcobalamin.

When taking Methylcobalamin, the B12 is already in its biologically active form.

Cyanocobalamin is the form found in most supplements because it’s far cheaper to make.

Methylcobalamin is generally more expensive and considered a more pure form, being in its natural, active state.

Methylcobalamin is the most bioavailable form of B12, so it is most readily absorbed. Research demonstrates that it stays in your bloodstream at higher levels compared to cyanocobalamin.

Methylcobalamin is the form best utilized by the liver, brain and nervous system.

Methylcobalamin has benefits to vision that cyanocobalamin does not. Research has shown that methylcobalamin significantly improves visual accommodation (the ability to shift focus from something nearby to something far away).

A study comparing the two forms showed that nearly three times as much cyanocobalamin was excreted through urine than methylcobalamin. This speaks to the bioavailability of methylcobalamin. The body is able to readily retain and utilize this source compared to cyanocobalamin, which is more apt to be excreted than utilized effectively.

Other forms of B12 include: Hydroxocobalamin and Adenosylcobalamin.

  • Hydroxocobalamin: This form is also natural, not synthetic. It is created by bacteria, found in food sources and constitutes for nearly half of the B12 found in our blood. Hydroxocobalamin circulates in the bloodstream longer than any other form of B12. It possesses a strong detoxifying effect, particularly to cyanide. Interestingly, hydroxocobalamin converts cyanide into cyanocobalamin, which is then secreted from the body. This, of course, poses the question—how effective then is cyanocobalamin supplementation? Smokers have high levels of cyanide as well as those who have been exposed to smoke inhalation. Hydroxocobalamin is utilized as a remedy to help detoxify the system in these cases. Hydroxocobalamin is also a scavenger of nitric oxide radicals, which are the culprit of multiple disease states: autoimmune diseases, psoriasis, asthma, heart attack, stroke, dementia, Alzheimer’s, Parkinson’s and cancer.
  • Adenosylcobalamin: Also known as Coenzyme B12, this form supports the Krebs cycle and cellular energy production down to the mitochondrial level. It also downregulates homocysteine levels, working with methyl folate to achieve this. Adenosylcobalamin also plays a vital role in carbohydrate, fat and protein metabolism, breaking them down to energy. Without this form of B12, food as energy would not be efficiently utilized by cells, leading to the possibility of mitochondrial issues, fatigue, exercise intolerance and other metabolic issues. 

What about B12 injections?

Many people rely on prescription B12 injections to elevate their levels. Those with pernicious anemia, an autoimmune disease that affects their ability to absorb and utilize B12, may feel that they need injectable B12 in order to achieve optimal levels. Most B12 injections are in cynocobalamin form. Even B12 injections with methylcobalamin, however, many contain harmful adjuvants, so request the package insert if you’re considering B12 injections.

Here is some information from the Package insert of B12 injections:

  1. Contains Aluminum:

“Cyanocobalamin injection contains aluminum, and aluminum toxicity may occur with prolonged administration in high-risk patients, including those with renal impairment and premature neonates. Premature neonates are at particular risk for aluminum toxicity because of immature renal function, and they require large amounts of calcium and phosphate solutions, which contain aluminum. Research indicates that patients with renal impairment, who receive parenteral aluminum at more than 4 to 5 mcg/kg/day, may develop aluminum-related CNS and bone toxicities. Tissue loading may occur at lower administration rates.”

  1. Contains Benzyl Alcohol:

“Most formulations of cyanocobalamin injection contain benzyl alcohol as a preservative. Benzyl alcohol may cause allergic reactions. Cyanocobalamin injections should be used cautiously in those patients with benzyl alcohol hypersensitivity. Cyanocobalamin preparations containing benzyl alcohol should be avoided in premature neonates because benzyl alcohol has been associated with 'gasping syndrome,' a potentially fatal condition characterized by metabolic acidosis and CNS, respiratory, circulatory, and renal dysfunction.”


Our BioActive B12 is a high-quality VEGAN vitamin B12 complex utilizing three bioavailable forms: Methylcobalamin, Hydroxocobalamin and Adenosylcobalamin. This advanced formula includes ingredient forms that need no conversion in the liver in order to be available for use by your cells. As a sublingual supplement, BioActive B12 provides maximum absorption through the mucous membranes in the mouth. Just 4 drops equal 4000 mcg of B12.



Our Methyl B Complete contains five key nutrients that are involved in homocysteine metabolism: folate as calcium folinate and Quatrefolic® for increased bioactivity; Trimethylglycine (TMG); and vitamins B12 (a combination of Methylcobalamin & Adenosylcobalamin), B6, and B2 (riboflavin). This unique formula was created to support optimal methylation and help sustain healthy homocysteine levels. It is exceptional for those with defective MTHFR genes.



Our products are third party laboratory tested post-production for heavy metals and other contaminants. We are also cGMP Certified (Current Good Manufacturing Process) with strict FDA compliance.These are a few of the measures Pure TheraPro Rx uses to ensure the consistent quality and potency of our formulas. In addition, our production facility and formulas have physician and scientist oversight. We are also meticulous to ensure our supplements are free of all common allergens. In other words, what is on the label must be in the bottle - no fillers, no excipients, no junk.

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