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What is Adenosylcobalamin?

Paul Scott
Paul Scott

Adenosylcobalamin is one of the two active forms of vitamin B12. It plays an essential role in the production of blood and the maintenance of normal cerebral and nervous functioning in the human body. Also known as cobamamide or dibencozide, adenosylcobalamin occurs naturally in animal derived food types such as fish, meat, eggs, and milk. Vitamin B12 is synthesized commercially for use as a dietary supplement by a process of bacterial enzyme production. A deficiency of adenosylcobalamin can cause a variety of disorders in humans including pernicious anemia, infections, fatigue, and depression.

Vitamin B12 is actively present in the human body in the form of adenosylcobalamin and methylcobalamin. This complex vitamin is an important dietary component and plays an critical role in several essential biological functions. These include cellular metabolism, DNA synthesis, energy and blood production, fatty acid synthesis, and healthy brain and nervous system functioning. Adenosylcobalamin occurs naturally in a number of food types derived from animals such as eggs, milk, meat, and fish. Synthetic forms of the vitamin are produced from bacterial enzymes and include cyanocobalamin and hydroxocobalamin.

Individuals suffering from ringing in the ears may benefit from taking B12 supplements.
Individuals suffering from ringing in the ears may benefit from taking B12 supplements.

These synthetic variants form the basis of vitamin B12 supplements essential for those with diets deficient in the substance. Vitamin B12 supplements are of particular value to groups such as vegans whose diets exclude animal products typically rich in vitamin B12. Other groups which may benefit from taking supplements include ex-smokers, the elderly, and those suffering from anemia, HIV, tinnitus, bursitism, and hives. Pregnant women often suffer from vitamin B12 deficiencies and may also benefit from taking adenosylcobalamin on a supplemental basis.

Elderly people are prone to experiencing Vitamin B12 deficiencies.
Elderly people are prone to experiencing Vitamin B12 deficiencies.

Maintenance of adequate levels of the vitamin is an important factor for those whose dietary intake or preexisting medical conditions place them at risk of deficiency. Low levels of the vitamin in the body may lead to serious and irreversible damage and even small fluctuations in B12 levels can have severe side effects. These include memory impairment, depression, chronic fatigue, and even symptoms of psychosis. Adenosylcobalamin deficiency may also lead to fibric sclerosis of nerve tissue. The most common syndrome of vitamin B12 shortages, though, is Biermans disease or pernicious anemia.

B-complex supplements typically contain adenosylcobalamin.
B-complex supplements typically contain adenosylcobalamin.

Vitamin B12 is available in tablet form or as an injection and is also used to fortify many foods such as breakfast cereals. The recommended dietary reference intake of vitamin B12 for adults is between 2 and 3 micrograms per day. The recommended dosage for women during pregnancy and lactation is 2.6 and 2.8 micrograms per day respectively. Adenosylcobalamin has a very low toxicity rating and allergic reactions are rare. Nevertheless, a doctor should be consulted prior to taking it as a supplement.

Discussion Comments

anon958635

I am extremely deficient in b12, folate and many other nutrients due to malabsorbtion and methylation issues. I take 10,000 mg of sublingual methyl b12, but it doesn't absorb. I would like to find an affordable source for adenosylcobalamin to give myself shots. Does anyone know a source?

anon337793

It's good, but I want to know if since I am taking methylcobalamin that now I need to take adenosylcobalamin?

shell4life

I'm glad that for me, an adenosylcobalamin deficiency was easy to fix. All I had to do was start eating the right things, and I began to feel so much better.

I had been suffering from fatigue, and I was depressed most of the time. I really didn't eat enough meat, and the only milk I ever consumed was a spoonful here and there with my cereal.

After I learned what was causing my physical and mental issues, I began incorporating more meat and fish into my diet. I made it a point to drink the milk leftover in my cereal bowl, and I started eating scrambled eggs three times a week.

I had so much more energy than before. I would never have guessed that animal products could make me feel so vital!

kylee07drg

@seag47 – Those vitamin B12 injections had side effects that I couldn't tolerate. I had been suffering from malnutrition after my husband died, because I just couldn't bring myself to eat much, so I developed an adenosylcobalamin deficiency. My doctor thought that the shots would be the best way to get my levels back on track as I went through the grieving process, because it was hard for me to eat.

Right after my first injection, I began to feel nauseous. That was no good, because I really couldn't eat anything feeling that way.

Within a few hours, my skin had started to swell. I broke out in hives, and I had to rush back to my doctor. She determined that I was not a good candidate for receiving B12 injections.

seag47

@StarJo – I don't think it is possible to overdose on vitamin B12. Even people who consume a lot of foods containing it can only absorb a certain percentage of the adenosylcobalamin in the food, because that is how our bodies are designed. The rest comes out when you defecate.

I recently had to start taking vitamin B12 injections. I had been feeling very fatigued for over a month, and when I asked my doctor about this, she tested me for a B12 deficiency.

I started out having the injections daily, but over time, my doctor reduced this to weekly, and now, I only get one once a month. She told me that as my B12 levels started to get back to normal, I would not need the injections so frequently.

StarJo

I certainly don't think I'm at any risk of developing an adenosylcobalamin deficiency. My diet consists mostly of meat, fish, and dairy products. I also eat eggs for breakfast almost every day, so if anything, I might be getting too much of it!

I wonder if it is possible to consume too much of this vitamin? Does anyone know if you can overdose on B12? What are the side effects of consuming too many foods that contain adenosylcobalamin?

I haven't been feeling unwell at all. Unless there are some secret side effects that include internal organ damage or something else I would remain unaware of, I must not be overdosing on it.

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    • Individuals suffering from ringing in the ears may benefit from taking B12 supplements.
      By: Von Schonertagen
      Individuals suffering from ringing in the ears may benefit from taking B12 supplements.
    • Elderly people are prone to experiencing Vitamin B12 deficiencies.
      By: krutoeva
      Elderly people are prone to experiencing Vitamin B12 deficiencies.
    • B-complex supplements typically contain adenosylcobalamin.
      By: Nenov Brothers
      B-complex supplements typically contain adenosylcobalamin.
    • Adenosylcobalamin is found in milk, eggs and many other animal products.
      By: seqoya
      Adenosylcobalamin is found in milk, eggs and many other animal products.
    • A deficiency of adenosylcobalamin may cause fatigue.
      By: jedi-master
      A deficiency of adenosylcobalamin may cause fatigue.
    • Pregnant women may benefit from taking adenosylcobalamin as a supplement if they have a B12 deficiency.
      By: Alena Ozerova
      Pregnant women may benefit from taking adenosylcobalamin as a supplement if they have a B12 deficiency.
    • Overcoming the mental effects of low levels of B12 may require both supplements and counseling.
      By: Rob
      Overcoming the mental effects of low levels of B12 may require both supplements and counseling.