Limidax™ XR
Methylcobalamin (Methyl-B12 Vitamin) Overview, Benefits, and Sources


Methylcobalamin (Methyl-B12 Vitamin) Overview, Benefits, and Sources


Vitamin B12, methylcobalamin, is one of the essential vitamins. It is needed to protect RNA and DNA, to stimulate serotonin production, to protect brain cells and nerve cells, to support energy and immune function, and to improve mood.

Methylcobalamin is one type of Methyl-B12. There are 5 types of vitamin B12:

  • cobalamin
  • methylcobalamin
  • cyanocobalamin
  • adenosylcobalamin
  • hydroxocobalamin

The vitamin works with vitamin B9 (folic acid, folate) to help produce red blood cells and to ensure iron works better in the body.

The only thing that differentiates methylcobalamin from cyanocobalamin is that it contains metal-alkyl bonds and an extra methyl group. Methylcobalamin is the most common coenzyme type of Methyl-B12 in nature.

All types of vitamin B12 are set apart by the side-group joined to the central molecule. Adenosylcobalamin and methylcobalamin are co-enzymes, which means they are needed by the body for certain chemical reactions.

Methylcobalamin’s effects are very similar to those of the other types of vitamin B12.

Other Names

Hydroxocobalamin, cobamamide, 5-deoxyadenosylcobalamin, cobalamin, cyanocobalamin, adenosylcobalamin, methylcobalamin, dibencozide.


Sources of Methylcobalamin

The best food sources of methylcobalamin are animal products, especially seafood and meats. This is because the vitamin is only produced by bacteria, most of which live in animals’ digestive systems. After the vitamin is produced by the bacteria, it is distributed throughout an animal’s body.

Food sources of methylcobalamin include fish, clams, liver, red meat, poultry, milk, and milk products. Vitamin B12 is found in very few plant foods; however, there are some fortified cereals that contain the vitamin.

Methylcobalamin can also be produced in a laboratory. Sodium borohydride is used to decrease cyanocobalamin in an alkaline solution after which methyl iodide is added.

Functions of Methylcobalamin

Methylcobalamin has a range of functions, both in the body and in the environment. In the environment, it decreases the toxicity of heavy metals in the soil, air, and water.

In the body, it offers anti-aging and neuro-protective benefits. Methylcobalamin also enhances signaling in the central nervous system and promotes neuron health and nerve function in the brain. The vitamin plays a role in maintaining the myelin sheath, the protective cover that contributes to nerve function and insulates nerve cells.

Methylcobalamin supports two key processes in the brain which offer longevity and neuro-protective benefits.  The first process it is involved in is getting rid of extra homocysteine in the brain. Homocysteine is said to be the main reason for vascular degeneration in the brain.

Homocysteine is found in meats and also created in the body through the breakdown of proteins. When its levels in the body are high, it may be an indicator that the methionine to cysteine metabolism is not functioning as it should. High homocysteine levels put one at risk for stroke and heart attack. They may also cause plaques to form along injured arterial walls.

The second function of methylcobalamin in the brain is to boost the function and the health of the brain’s nerves. It can help regrow damaged nerves and help maintain the function that decays during the aging process.

Methylcobalamin takes part in the methylation reaction and immune system function. It also plays a major role in red blood cell function and in the prevention of anemia. The vitamin is also involved in the creation of red blood cells. These cells contain hemoglobin, the protein that transports oxygen from the lungs to the rest of the body. When blood cell conditions like pernicious anemia occur in people with autoimmune disorders, they can lead to cognitive impairment, chronic fatigue, and immunity issues.

Like other B vitamins, methylcobalamin helps reduce stress both in the body and in the mind. It increases the amount of S-adenosylmethionine, the compound which improves mood and functions as a tricyclic antidepressant.

In relation to this, methylcobalamin is being researched for its impact on chronic fatigue and depression. There is also ongoing research to see whether methylcobalamin can be helpful for cancer, heart disease, and Bell’s palsy.


Methylcobalamin Benefits

Methyl-B12 is a popular treatment for anemia. Like other B vitamins, it helps improve stress and mood. It decreases high homocysteine levels and also fights heart disease. Many people supplement with vitamin B12 to relieve allergies and asthma and to improve sleep.

One of the vitamin’s best benefits is protecting the brain against age-related memory loss. Because of this, it is considered a vital longevity supplement that may increase a person’s years. It fights symptoms of aging at the cellular level. Taking a vitamin B12 supplement every day can help boost memory and increase mental energy and concentration. The vitamin also protects the brain against glutamate toxicity which is the main cause of brain cell death.

Another benefit of methyl-B12 is its ability to decrease the risk of some birth defects in unborn children. Expectant mothers with low serum levels of vitamin B12 can give birth to babies with spina fibida (a condition where the spinal cord doesn’t develop properly). In such cases, doctors may prescribe Vitamin B Complex prenatal supplement.

Methylcobalamin plays a role in nerve-related functions and works as a neuropathic pain reliever. It can regenerate damaged nerves and prevent neurotoxicity, giving pain relief to patients suffering from degenerative diseases like Alzheimer’s and arthritis.


Methylcobalamin Deficiency and Supplementation

Vegetarians and vegans can suffer from vitamin B 12 deficiency if they do not consume foods that contain it. Vitamin B12 deficiency often accompanies strict vegan or vegetarian diets.

However, many vegetarian and vegan-friendly foods contain cobalamin in order to prevent vitamin B12 deficiency. Nutritional yeast and Brewer’s yeast contain synthetic versions of methylcobalamin. Some vegans and vegetarians take supplements or yearly injections to prevent vitamin B12 deficiency.

There are very few plant-derived foods that contain high levels of vitamin B 12 that are ideal for vegetarians. They include tempe (which is made from fermented soybeans), dried purple laver (nori), spinach leaves, and some types of mushrooms.

Supplementing with methylcobalamin can increase the levels of vitamin B12 in people who have a deficiency. A test known as the methylmalonic acid test (MMA) can show whether there are low amounts of vitamin B12 in the body.

When the body has low levels of vitamin B12, methylmalonate, a waste product, builds up. Methylmalonic Acid begins to accumulate in the urine. The methylmalonic acid test is one of the best as it can detect a vitamin B12 deficiency in its early stages.

In days gone by, people with a vitamin B12 deficiency received monthly injections from doctors. However, research has proved that oral supplements are just as effective as injections.

Methylcobalamin’s Dosage

Methylcobalamin is usually taken in small dosages – 25 mg per day or less. Its benefits start to manifest after a few days. A dosage of 40 mg per day is recommended for serious cases of neuropathy. While methylcobalamin is considered safe at this high dose, it should be taken under the supervision of a doctor.

To protect your brain against age-related cognitive decline, take 1 mg per day – even before the symptoms start to manifest. You can mix the supplement with similar doses of pyridoxine and folic acid.

Vegans and vegetarians who seek to prevent vitamin B12 deficiency should take 25 mg to 100 mg per day.

Methylcobalamin’s Side Effects

While a moderate dosage of methylcobalamin is generally regarded as safe, some people have reported side effects like:

  • Increased heart rate
  • Shortness of breath
  • Stomach discomfort
  • Diarrhea
  • Itching, skin rash, hives
  • Pain in the chest or tightness
  • Allergic reactions like swelling of the face and lips

In rare cases, the vitamin can cause dangerous blood clots or tachycardia. People suffering from blood cell conditions like anemia or polycythemia should consult their health care providers before supplementing with methylcobalamin. This is because the supplement can cause unique side effects which must be monitored by a doctor.

Methylcobalamin supplements can interact with other substances and drugs such as chloramphenicol, colchicines, aminosalicylic acid, and alcohol. If you are taking medication, check with your healthcare practitioner before supplementing with methylcobalamin.

There are different types of methylcobalamin supplements: oral tablets, sublingual lozenges, sprays, liquid drops, and transdermal creams. The dosages range from 0.5 mg to 6 mg. Transdermal creams are applied to the skin and don’t have any negative side effects. However, in very unique cases, they can cause a rash in people with pre-existing allergies or those who are hypersensitive to vitamin B12.

All of the B vitamins are crucial for many physical and neurological functions. Because of this, supplementing with methyl- B12 may be necessary, especially for people who don’t get it from food.

About the Author

Limidax Team

The Limidax Team includes neuroscientists, researchers, and health coaches. We hope you find these articles useful. If you have any questions at all, always feel free to reach out to us.