Vitamin B12 (cobalamin)

Vitamin B12, also known as cobalamin, is an essential nutrient that plays a key role in many biological processes.

It supports the normal functioning of the nervous system, participates in the formation of red blood cells, and is involved in DNA synthesis.

Health Benefits

Metabolism. It is involved in converting fats into energy, making it important for maintaining energy levels in the body.

It also helps in converting food into glucose.

Myelin production occurs with the participation of vitamin B12.

Myelin forms a protective sheath around nerve fibers, aiding in the transmission of nerve impulses.

Heart Health. Vitamin B12 may lower homocysteine levels – a substance associated with an increased risk of cardiovascular diseases.

Daily Requirement and Sources

Daily requirement for vitamin B12 varies depending on age, gender, and health status. For adults, the recommended daily dose is about 2.4 mcg, while pregnant and breastfeeding women may require more.

Sources of vitamin B12 include animal products such as meat, fish, dairy products, and eggs.

Vegans and people with certain conditions that hinder B12 absorption may need to take supplements or consume fortified foods.

Possible forms and their learnability

Nutrient forms are listed from best to worst:

Methylcobalamin. This is one of the active coenzyme forms of vitamin B₁₂, which directly participates in the metabolic processes of the body. Methylcobalamin is especially important for the health of the nervous system and DNA synthesis. It is easily absorbed and effective when taken orally.

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Swanson, Vitamin B12, (Methylcobalamin), Natural Black Cherry, 2,500 mcg, 60 Tablets

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Bluebonnet Nutrition, EarthSweet Chewables, Methylcobalamin, Raspberry , 1,000 mcg, 60 Chewable Tablets	11.51
Natural Factors, B12, Methylcobalamin, 1,000 mcg, 90 Chewable Tablets	9.43
Natural Factors, B12, Methylcobalamin, 1,000 mcg, 180 Chewable Tablets	15.71
Sundance Vitamins, Fast Dissolve Methylcobalamin B-12, Natural Berry, 1,000 mcg, 150 Fast Dissolve Tablets	12.83
Source Naturals, MethylCobalamin, Cherry, 1 mg, 60 Lozenges	8.85
Source Naturals, MethylCobalamin Vitamin B12, Cherry, 1 mg, 120 Lozenges	16.21
Source Naturals, Vegan True, MethylCobalamin Vitamin B-12, Cherry , 1 mg, 60 Lozenges	8.85
Source Naturals, MethylCobalamin Vitamin B12, Cherry, 1 mg, 240 Lozenges	25.46
Superior Source, Methylcobalamin B-12, 2,500 mcg, 90 Instant Dissolve Tablets	22.36

Adenosylcobalamin (dibencozide). Another active form of vitamin B₁₂ that plays a key role in energy metabolism and mitochondrial function. Adenosylcobalamin is important for maintaining energy and the health of the nervous system.

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NOW Foods, B-12, 2,000 mcg, 100 Lozenges

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Hydroxocobalamin. The natural form of vitamin B₁₂, often used in medicine to treat B₁₂ deficiency and cyanide poisoning. Hydroxocobalamin has good bioavailability and can be converted into active forms (methylcobalamin and adenosylcobalamin) in the body.

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Source Naturals, HydroxoCobalamin, Vitamin B12, Cherry , 1 mg, 120 Lozenges

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Source Naturals, HydroxoCobalamin, Cherry, 1 mg, 60 Lozenges	8.10
Source Naturals, HydroxoCobalamin, Vitamin B-12, Cherry, 1 mg, 240 Lozenge	28.45

Cyanocobalamin. The synthetic form of vitamin B₁₂, widely used in supplements and fortified foods. In the body, cyanocobalamin must be converted into active forms (methylcobalamin or adenosylcobalamin) before use. Although it is stable and inexpensive to produce, its absorption may be less effective compared to the aforementioned forms.

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Superior Source, Cyanocobalamin B-12 & Folic Acid, 100 MicroLingual Instant Dissolve Tablets	15.82
Superior Source, Cyanocobalamin B-12 & Folic Acid, 60 MicroLingual Instant Dissolve Tablets	8.85
Superior Source, Cyanocobalamin & B-12 & B-6 & Folic Acid, 1,000 mcg & 2 mg & 400 mcg, 60 MicroLingual Instant Dissolve Tablets	11.58
Superior Source, Cyanocobalamin B-12, B-6 & Folic Acid, 100 MicroLingual Instant Dissolve Tablets	15.05
Superior Source, Cyanocobalamin B-12, B-6 & Folic Acid, 60 MicroLingual Instant Dissolve Tablets	9.74
Superior Source, B-12 (Cyanocobalamin), 5,000 mcg, 100 MicroLingual Instant Dissolve Tablets	31.29
Superior Source, Cyanocobalamin B-12, 10,000 mcg, 60 MicroLingual Instant Dissolve Tablets	22.08
Swanson, Vitamin B12, (Cyanocobalamin), 500 mcg, 250 Capsules	10.42
Swanson, Vitamin B12 Cyanocobalamin, Triple Action, 1,000 mcg, 90 Tablets	10.07
Swanson, B12 Cyanocobalamin Liquid, Strawberry, 2 fl oz (59 ml)	16.17

Symptoms and Consequences of Deficiency

A deficiency of vitamin B12 can lead to numerous adverse symptoms, including fatigue, weakness, constipation, loss of appetite, and weight loss.

Numbness. Additionally, a lack of this vitamin can cause nerve issues such as numbness and tingling in the hands and feet.

Anemia. Prolonged deficiency of vitamin B12 can lead to serious consequences, including the development of megaloblastic anemia, memory impairment, and damage to the nervous system.

Mental Disorders. Deficiency can lead to depression, confusion, and even dementia.

Potential Risks of Excess Intake

Excess vitamin B12 in the human body usually does not cause serious problems, as it is water-soluble and excess amounts are excreted in urine.

In general, vitamin B12 is unique among water-soluble vitamins. On one hand, its excess can be excreted in urine. On the other hand, the body can store excess vitamin B12 in the liver for future use.

In some cases, especially with significant excess intake through supplements, excessive accumulation of the vitamin may occur, potentially leading to undesirable consequences.

Such side effects may include dermatological reactions such as acne, headaches, and anxiety, as well as cardiovascular system disturbances.

In particular, the risk of thrombosis may increase due to elevated homocysteine levels in the blood with excessive vitamin B12 intake. It is important to emphasize that such cases are extremely rare and most often associated with prolonged high doses of the vitamin without medical supervision.

Myths and Misconceptions

Is vitamin B12 deficiency easy to detect? Symptoms of vitamin B12 deficiency can develop slowly and manifest over months or even years, making it difficult for timely diagnosis.

Is vitamin B12 absorbed equally in people of all ages? In fact, older adults often have a higher risk of vitamin B12 deficiency due to decreased absorption in the body, and they may need more of this vitamin.

Can vitamin B12 be obtained from mushrooms? Although some mushrooms contain a vitamin B12 analog, it is not a complete source as it does not provide all the necessary functions of this vitamin.

Interesting Facts

The origin of the name cobalamin. This name comes from cobalt, which is the central atom in its molecule.

Cobalamin was discovered in 1948 and is considered one of the most complex vitamins in terms of its structure.

Storage in the body. This vitamin is stored in the liver and can remain in the body for several years, making its deficiency gradually developing.

Predisposition to deficiency. Some individuals may have a genetic predisposition to vitamin B12 deficiency due to mutations in the genes responsible for its absorption and transport.

Some algae contain vitamin B12. For example, nori (used for sushi) can be a source of this vitamin, though its content may vary.

Forms of vitamin B12 include methylcobalamin, adenosylcobalamin, hydroxocobalamin, and cyanocobalamin. Each has its own absorption and application characteristics.

Some medications can reduce vitamin B12 levels. For instance, medications for treating heartburn and diabetes may affect the absorption of this vitamin, requiring monitoring of B12 levels in patients.