The Different Forms of B12 Cyanocobalamin and Methylcobalamin

The Different Forms of B12 Cyanocobalamin and Methylcobalamin
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Vitamin B12 is the largest and most structurally complicated of the B vitamins. B12 is a crucial nutrient that is involved in many essential bodily functions. It plays a role in maintaining healthy nerve cells, improving bone health, ensuring cognitive functionality, synthesizing DNA and RNA, and producing healthy red blood cells. As a water-soluble vitamin, B12 dissolves in water and moves effortlessly through your bloodstream.

Not all forms of B12 are created equal, each featuring its own set of unique properties and benefits. Forms of B12 differ in several ways, such as chemical structure, metabolic pathways, and absorption rate, and it’s crucial to understand how these differences can make a difference to our general health and well-being. This article discusses the four types of vitamin B12: cyanocobalamin, methylcobalamin, hydroxocobalamin, and adenosylcobalamin, and their purported benefits so that you can make an informed decision about which form best suits your needs.

Sources of Vitamin B12

Vitamin B12, or cobalamin, is essential for our health and well-being. This vitamin is naturally found in various animal products, such as red meat, poultry, dairy, eggs, and fish. Vitamin B12 is also available in supplement form to meet the needs of those with difficulties absorbing vitamin B12 from food sources. Vitamin B12 supplements come in oral and sublingual forms, such as tablets or lozenges.

Daily Vitamin B12 Intake Requirements

The National Institutes of Health (NIH) states that individuals over the age of 14 need 2.4 micrograms of vitamin B12 to fulfill their recommended dietary allowance. Pregnant women have a slightly higher intake recommendation of 2.6 mcg while lactating individuals are advised to consume 2.8 mcg of vitamin B12 daily. Vitamin B12 deficiency is developed if you’re not eating enough vitamin B12-rich foods or if your body has an inadequate intrinsic factor, a protein that helps your blood and cells absorb vitamin B12. Individuals planning to take vitamin B12 supplements should get the advice of their healthcare provider regarding the proper dosage that fits their specific health needs.

Side Effects of Vitamin B12 Deficiency

Older individuals, pregnant and nursing women, vegans, vegetarians, and those who have undergone stomach surgery are most at risk of developing vitamin B12 deficiency. A mild deficiency won’t create any huge issues. However, a small deficiency can lead to several complications if left unresolved. Some symptoms associated with vitamin B12 deficiency include extreme fatigue, memory loss, depression, numbness, and anemia.

Pernicious Anemia

Pernicious anemia is a medical condition that causes vitamin B12 deficiency. Though rare, pernicious anemia produces a decrease in red blood cells due to autoimmune stomach inflammation and the small intestine’s inability to absorb vitamin B12. Treatment of the condition includes vitamin B12 injections to restore ideal levels of vitamin B12. Afterward, long-term injections or oral medications are used to maintain healthy vitamin B12 levels.

Cardiovascular Issues

According to research, low levels of vitamin B12 result in an increase in a protein called homocysteine. High homocysteine levels place one at a higher risk of developing coronary artery disease or stroke. An increase in homocysteine elevates the possibility of blood clots forming and an excess of free radical cells, resulting in a weakened normal blood vessel function.

Cognitive Impairment

Vitamin B12 deficiency is associated with impaired cognition and memory loss, accompanied by a sensation of tingling and numbness. Studies also link high homocysteine levels with a higher risk of developing Alzheimer’s disease, dementia, and cognitive decline.

The Four Types of Vitamin B12

Taking Vitamin B12 supplements provides a reliable and convenient solution for those with a B12 deficiency. This important vitamin comes in four nearly identical chemical forms: namely, cyanocobalamin, methylcobalamin, adenosylcobalamin, and hydroxocobalamin.


As per the Office of Dietary Supplements, cyanocobalamin is the most common form of vitamin B12 found in dietary supplements. Cyanocobalamin is a manufactured form of B12 that can only be acquired in supplements and fortified foods. Once consumed, this form of vitamin B12 is converted to either methylcobalamin or adenosylcobalamin, two active forms of B12 in the human body. Due to its synthetic form, cyanocobalamin offers a cost-efficient and stable way of increasing your vitamin B12 levels along with a long shelf life.


Methylcobalamin is the most active form of vitamin B12 in the human body. This B12 type promotes a healthier liver, brain, and nervous system. Unlike cyanocobalamin, methylcobalamin is available in both supplements and natural food sources, such as fish, meat, and eggs. This form of vitamin B12 also plays a role in converting homocysteine, an amino acid that increases one’s risk of developing dementia and heart issues, into methionine.


Adenosylcobalamin is a naturally occurring coenzyme form of vitamin B12 that helps support and safeguard the mitochondria in your cells. This form of Vitamin B12 assists the mitochondria in each cell with burning food, producing energy, and improving metabolism. Adenosylcobalamin also helps create cellular energy and prevents DNA and RNA damage that can lead to aging-related issues.


The human body readily converts the naturally-produced hydroxocobalamin into adenosylcobalamin and methylcobalamin so its cells can easily absorb and use them. Bacteria create this type of vitamin B12 while food is being broken down in the digestive tract. Hydroxocobalamin is mostly present in animal-based sources like red meat, fish, and eggs. This form of vitamin B12 promotes smooth red blood cell formation, excellent immune system functionality, and improved mood.


Vitamin B12 supplements are safe and non-toxic when taken in safe dosages. Excessive intake over an extended period can result in an imbalance of other essential B vitamins. It’s vital that you take dietary supplements under the supervision of a knowledgeable and trusted healthcare provider. Vitamin B12 supplements have the potential to interact with and compromise the efficacy of a number of medications.

In Conclusion

Vitamin B12 is vital for many bodily functions, such as promoting healthy nerve cells, synthesizing DNA, and producing red blood cells. B12 is available in animal food sources like red meat, eggs, and fish, as well as in supplement form. The four types of vitamin B12 included in supplements are cyanocobalamin, methylcobalamin, adenosylcobalamin, and hydroxocobalamin. Understanding the different types is essential in helping people make informed decisions and preventing the risks of vitamin B12 deficiency.

Quill Brad