Table of ContentsView AllTable of ContentsMethylcobalamin vs. CyanocobalaminBioavailability and AbsorptionHealth BenefitsWho’s at Risk of a B12 Deficiency?Special Considerations
Table of ContentsView All
View All
Table of Contents
Methylcobalamin vs. Cyanocobalamin
Bioavailability and Absorption
Health Benefits
Who’s at Risk of a B12 Deficiency?
Special Considerations
Methylcobalaminandcyanocobalaminare two different forms of vitamin B12. Although both are used in supplements and can increase B12 levels, they each have a different structure and source.
In additional to treating vitamin B12 deficiencies, methylcobalamin and cyanocobalamin treat health conditions such as pernicious anemia and nerve pain. Both forms are considered generally safe but may interact with certain medications.
A bottle of methylcobalamin (vitamin B12).MediaNews Group / Reading Eagle via Getty Images / Contributor / Getty Images
MediaNews Group / Reading Eagle via Getty Images / Contributor / Getty Images
Methylcobalamin and cyanocobalamin are the two forms ofvitamin B12most commonly used in dietary supplements. Both provide health benefits but they differ in their structure and sources.
Because methylcobalamin and cyanocobalamin are most often used to increase vitamin B12 levels, it’s essential to be familiar with recommended daily intakes.
The recommended dietary allowances (RDAs) for vitamin B12 are as follows:
People who arepregnantor lactating require higher amounts of B12. During pregnancy, 2.6 mcg of vitamin B12 is recommended. Whilebreastfeeding, 2.8 mcg of B12 is recommended.
Two Different Forms of Cobalamin
Methylcobalamin is a natural form of vitamin B12, and cyanocobalamin is synthetic. The two forms also differ in structure—methylcobalamin contains a methyl group, and cyanocobalamin contains a cyanide molecule.
There is a misconception regarding the safety of the cyanide found in cyanocobalamin. The truth is that the amount of cyanide is minuscule and eliminated from your body, so it isn’t a concern.
Both forms of B12 are available in supplements, but cyanocobalamin is used more often due to its lower cost and higher heat stability. Cyanocobalamin is also used to fortify certain foods to increase their value of vitamin B12.
Because methylcobalamin is a natural source of vitamin B12, it is found in animal-based foods like meat, fish, poultry, eggs, and dairy products.
During digestion, your body removes the methyl group from methylcobalamin or the cyanide molecule from cyanocobalamin. The remaining cobalamin molecule is absorbed and turned into an active form of vitamin B12 that your body can use (methylcobalamin).
According to one review, methylcobalamin and other natural sources of B12 are more bioavailable than synthetic forms like cyanocobalamin.However, a small study from 2021 argues that differences in bioavailability between the two forms are negligible and that cyanocobalamin may maintain serum levels better.
More research may be necessary regarding bioavailability, but both forms of B12 have been found to provide health benefits.
Is Methylcobalamin Better Than Cyanocobalamin?Some experts suggest methylcobalamin is better because it’s the natural form your body uses and is more bioavailable.Other researchers suggest that cyanocobalamin does a better job maintaining B12 levels.Overall, there isn’t evidence proving that one form is better than the other, and both increase vitamin B12 levels.
Is Methylcobalamin Better Than Cyanocobalamin?
Some experts suggest methylcobalamin is better because it’s the natural form your body uses and is more bioavailable.Other researchers suggest that cyanocobalamin does a better job maintaining B12 levels.Overall, there isn’t evidence proving that one form is better than the other, and both increase vitamin B12 levels.
Vitamin B12 is an essential nutrient, which means you need to get it from food or supplements throughout your life. Your body can’t make B12 on its own.
Vitamin B12 is vital to the function and development of yourcentral nervous systemand is necessary to make red blood cells andDNA.
The optimal dose and whether you need oral supplements or injections depends on the condition and your current B12 levels.
Certain people may be at a higher risk of developing a vitamin B12 deficiency, including:
If left untreated, a deficiency in B12 can lead to nerve damage. Therefore, early diagnosis of vitamin B12 deficiency is essential. A deficiency can also cause fatigue, megaloblastic anemia, dementia, weight loss, and infertility.
Vitamin B12 supplements are generally safe, even in high doses because your body doesn’t absorb the full amount.However, using methylcobalamin, cyanocobalamin, or other B12 supplements may pose the following risks:
Cobalt Allergy
People with acobalt allergyor sensitivity should talk with a healthcare provider before using vitamin B12 supplements. All forms of B12 contain cobalt (cobalamin).Taking vitamin B12 may causecontact dermatitisif you have a severe allergy.
Medication Interactions
Certain medications reduce the absorption of methylcobalamin, cyanocobalamin, and other B12 supplements, including:
If you use these or other medications, talk with a healthcare provider about ways to maintain healthy levels of B12.
Summary
Methylcobalamin and cyanocobalamin are two forms of vitamin B12 used in supplements. While methylcobalamin is naturally found in foods, cyanocobalamin is synthetically produced. Cyanocobalamin is often preferred for supplements because it’s less expensive and more stable.
In research, methylcobalamin and cyanocobalamin have beneficial effects on various health conditions, including B12 deficiency and pernicious anemia. They may also improve ALS, neuropathic pain, and other conditions. B12 supplements are generally considered safe but can interact with certain medicines.
11 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Institutes of Health: Office of Dietary Supplements.Vitamin B12: fact sheet for health professionals.National Institutes of Health Office of Dietary Supplements.Vitamin B12: fact sheet for health professionals.Paul C, Brady DM.Comparative bioavailability and utilization of particular forms of B12 supplements with potential to mitigate B12-related genetic polymorphisms.Integr Med (Encinitas). 2017;16(1):42-49.Zugravu CA, Macri A, Belc N, Bohiltea R.Efficacy of supplementation with methylcobalamin and cyancobalamin in maintaining the level of serum holotranscobalamin in a group of plant-based diet (vegan) adults.Exp Ther Med. 2021;22(3):993. doi:10.3892/etm.2021.10425National Institute of Neurological Disorders and Stroke.Peripheral neuropathy.Julian T, Syeed R, Glascow N, et al.B12 as a treatment for peripheral neuropathic pain: a systematic review.Nutrients. 2020;12(8):2221. doi:10.3390/nu12082221Chan CQH, Low LL, Lee KH.Oral vitamin B12 replacement for the treatment of pernicious anemia.Front Med (Lausanne). 2016;3:38. doi:10.3389/fmed.2016.00038Jiang JS, Wang Y, Deng M.New developments and opportunities in drugs being trialed for amyotrophic lateral sclerosis from 2020 to 2022.Front Pharmacol. 2022;13:1054006. doi:10.3389/fphar.2022.1054006National Institutes of Health: Office of Dietary Supplements.Vitamin B12: fact sheet for health professionals.Oregon State University, Linus Pauling Institute.Vitamin B12.Brescoll J, Daveluy S.A review of vitamin B12 in dermatology.Am J Clin Dermatol. 2015;16(1):27-33. doi:10.1007/s40257-014-0107-3
11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Institutes of Health: Office of Dietary Supplements.Vitamin B12: fact sheet for health professionals.National Institutes of Health Office of Dietary Supplements.Vitamin B12: fact sheet for health professionals.Paul C, Brady DM.Comparative bioavailability and utilization of particular forms of B12 supplements with potential to mitigate B12-related genetic polymorphisms.Integr Med (Encinitas). 2017;16(1):42-49.Zugravu CA, Macri A, Belc N, Bohiltea R.Efficacy of supplementation with methylcobalamin and cyancobalamin in maintaining the level of serum holotranscobalamin in a group of plant-based diet (vegan) adults.Exp Ther Med. 2021;22(3):993. doi:10.3892/etm.2021.10425National Institute of Neurological Disorders and Stroke.Peripheral neuropathy.Julian T, Syeed R, Glascow N, et al.B12 as a treatment for peripheral neuropathic pain: a systematic review.Nutrients. 2020;12(8):2221. doi:10.3390/nu12082221Chan CQH, Low LL, Lee KH.Oral vitamin B12 replacement for the treatment of pernicious anemia.Front Med (Lausanne). 2016;3:38. doi:10.3389/fmed.2016.00038Jiang JS, Wang Y, Deng M.New developments and opportunities in drugs being trialed for amyotrophic lateral sclerosis from 2020 to 2022.Front Pharmacol. 2022;13:1054006. doi:10.3389/fphar.2022.1054006National Institutes of Health: Office of Dietary Supplements.Vitamin B12: fact sheet for health professionals.Oregon State University, Linus Pauling Institute.Vitamin B12.Brescoll J, Daveluy S.A review of vitamin B12 in dermatology.Am J Clin Dermatol. 2015;16(1):27-33. doi:10.1007/s40257-014-0107-3
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
National Institutes of Health: Office of Dietary Supplements.Vitamin B12: fact sheet for health professionals.National Institutes of Health Office of Dietary Supplements.Vitamin B12: fact sheet for health professionals.Paul C, Brady DM.Comparative bioavailability and utilization of particular forms of B12 supplements with potential to mitigate B12-related genetic polymorphisms.Integr Med (Encinitas). 2017;16(1):42-49.Zugravu CA, Macri A, Belc N, Bohiltea R.Efficacy of supplementation with methylcobalamin and cyancobalamin in maintaining the level of serum holotranscobalamin in a group of plant-based diet (vegan) adults.Exp Ther Med. 2021;22(3):993. doi:10.3892/etm.2021.10425National Institute of Neurological Disorders and Stroke.Peripheral neuropathy.Julian T, Syeed R, Glascow N, et al.B12 as a treatment for peripheral neuropathic pain: a systematic review.Nutrients. 2020;12(8):2221. doi:10.3390/nu12082221Chan CQH, Low LL, Lee KH.Oral vitamin B12 replacement for the treatment of pernicious anemia.Front Med (Lausanne). 2016;3:38. doi:10.3389/fmed.2016.00038Jiang JS, Wang Y, Deng M.New developments and opportunities in drugs being trialed for amyotrophic lateral sclerosis from 2020 to 2022.Front Pharmacol. 2022;13:1054006. doi:10.3389/fphar.2022.1054006National Institutes of Health: Office of Dietary Supplements.Vitamin B12: fact sheet for health professionals.Oregon State University, Linus Pauling Institute.Vitamin B12.Brescoll J, Daveluy S.A review of vitamin B12 in dermatology.Am J Clin Dermatol. 2015;16(1):27-33. doi:10.1007/s40257-014-0107-3
National Institutes of Health: Office of Dietary Supplements.Vitamin B12: fact sheet for health professionals.
National Institutes of Health Office of Dietary Supplements.Vitamin B12: fact sheet for health professionals.
Paul C, Brady DM.Comparative bioavailability and utilization of particular forms of B12 supplements with potential to mitigate B12-related genetic polymorphisms.Integr Med (Encinitas). 2017;16(1):42-49.
Zugravu CA, Macri A, Belc N, Bohiltea R.Efficacy of supplementation with methylcobalamin and cyancobalamin in maintaining the level of serum holotranscobalamin in a group of plant-based diet (vegan) adults.Exp Ther Med. 2021;22(3):993. doi:10.3892/etm.2021.10425
National Institute of Neurological Disorders and Stroke.Peripheral neuropathy.
Julian T, Syeed R, Glascow N, et al.B12 as a treatment for peripheral neuropathic pain: a systematic review.Nutrients. 2020;12(8):2221. doi:10.3390/nu12082221
Chan CQH, Low LL, Lee KH.Oral vitamin B12 replacement for the treatment of pernicious anemia.Front Med (Lausanne). 2016;3:38. doi:10.3389/fmed.2016.00038
Jiang JS, Wang Y, Deng M.New developments and opportunities in drugs being trialed for amyotrophic lateral sclerosis from 2020 to 2022.Front Pharmacol. 2022;13:1054006. doi:10.3389/fphar.2022.1054006
Oregon State University, Linus Pauling Institute.Vitamin B12.
Brescoll J, Daveluy S.A review of vitamin B12 in dermatology.Am J Clin Dermatol. 2015;16(1):27-33. doi:10.1007/s40257-014-0107-3
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