Vitamin B12: Benefits, Deficiency, Sources, and More

vitamin b12

Vitamin B12, also known as cobalamin, is an essential vitamin that plays a pivotal role in various bodily functions. It is an essential nutrient required for maintaining overall health, and its deficiency can lead to a range of health problems. In this article, we explore the various aspects of vitamin B12, including its benefits, sources, functions, deficiency symptoms, side effects, and recommended intake.


What is Vitamin B12?


Vitamin B12 is a complex and structurally unique vitamin that contains cobalt at its core, hence the name cobalamin. (1) It is a part of the B-vitamin family, a group of essential vitamins that play crucial roles in energy metabolism and various biochemical reactions in the body.


What Does Vitamin B12 Do?

vitamin b12 


Vitamin B12 serves several vital functions in the body:


1. Red Blood Cell Formation:


Vitamin B12 is essential for the synthesis of hemoglobin, a protein in red blood cells that carries oxygen from the lungs to various tissues and organs. Without sufficient amounts of B12, red blood cell production is impaired, leading to anemia. (2)


2. Nervous System Health:


It plays a pivotal role in maintaining the health of the nervous system by helping to form the myelin sheath that surrounds and protects nerve fibers. A deficiency can result in neurological problems, including tingling sensations, numbness, and even neurological damage in severe cases. (3)


3. DNA Synthesis:


Vitamin B12 is necessary for DNA synthesis, cell division, and the repair of damaged cells, which is particularly important for rapidly dividing cells in tissues like the bone marrow and the gastrointestinal tract. (4)


4. Homocysteine Metabolism:


B12 is involved in the breakdown of the amino acid homocysteine. High levels of this amino acid in the blood have been associated with an elevated risk of cardiovascular disease, making B12 important for heart health. (5)


Vitamin B12 Benefits

woman exercising 


As an essential nutrient, vitamin B12 plays many important roles in the body. Some of the top benefits of vitamin B12 include:


  1. Energy Production: Vitamin B12 plays a vital role in converting food into energy, helping combat fatigue, and promoting overall vitality. 
  2. Mood Regulation: Adequate B12 levels are linked to improved mood and may help in managing symptoms of depression and anxiety. 
  3. Cognitive Function: B12 is crucial for maintaining cognitive health and may contribute to better memory and mental clarity.
  4. Heart Health: By lowering homocysteine levels, B12 supports heart health and function, reducing the risk of cardiovascular diseases. 
  5. Healthy Skin and Hair: B12 contributes to healthy skin, hair, and nails, as it plays an important role in cell reproduction and renewal. (6)


Vitamin B12 Foods

b12 foods


While vitamin B12 is primarily found in animal-derived foods, there are some plant-based sources and fortified foods available. Here are some common sources of vitamin B12:


1. Animal Products:

  • Meat (beef, pork, lamb)
  • Poultry (chicken, turkey)
  • Fish (salmon, trout, tuna)
  • Dairy products (milk, cheese, yogurt)
  • Eggs


2. Fortified Foods:

  • Breakfast cereals
  • Plant-based milk alternatives (soy, almond, coconut milk)
  • Nutritional yeast


3. Supplements:

  • There are many Vitamin B12 supplements available, including capsules, pills, and sublingual (under the tongue) drops. These are commonly used by individuals with dietary restrictions or absorption issues.


4. Organ Meats:

  • Liver and kidney from animals are exceptionally rich sources of vitamin B12.


Symptoms of Vitamin B12 Deficiency


A deficiency in vitamin B12 can have serious health consequences. Common symptoms and signs of deficiency include:


  • Fatigue and weakness
  • Anemia
  • Numbness
  • Tingling in the hands and feet
  • Difficulty walking and balance problems
  • Memory loss and cognitive difficulties
  • Mood changes, including depression and irritability
  • Pale or jaundiced skin
  • Glossitis (inflamed tongue) and mouth ulcers
  • Heart palpitations (2)


If left untreated, a deficiency of this important nutrient can potentially lead to irreversible nerve damage and severe neurological complications. (2)


Vitamin B12 Side Effects


Vitamin B12 is generally safe when consumed through food sources and appropriate supplements. However, excessive intake through high-dose supplements can lead to certain side effects, including:


  • Skin rashes
  • Itching
  • Nausea
  • Diarrhea
  • Headache
  • Anxiety


These side effects are rare and usually occur when extremely high doses are consumed. It's essential to follow recommended daily intake guidelines.


How Much Vitamin B12 Should I Take?

b12 dosage


The recommended daily amount of vitamin B12 can vary by age, sex, and life stage. As a general guideline:


  • Infants (0-6 months): 0.4 micrograms (mcg)
  • Infants (7-12 months): 0.5 mcg
  • Children (1-3 years): 0.9 mcg
  • Children (4-8 years): 1.2 mcg
  • Adolescents (9-13 years): 1.8 mcg
  • Adults (14+ years): 2.4 mcg
  • Pregnant and breastfeeding women might require higher amounts of vitamin B12, with recommendations ranging from 2.6 to 2.8 mcg per day.


Best Vitamin B12 Supplements

b12 supplement


When choosing a B12 supplement, it's essential to consider your dietary restrictions and individual needs. Common forms of B12 supplements include:


  • Cyanocobalamin: The most stable and widely used form of B12.
  • Methylcobalamin: A more bioactive form that may be beneficial for some individuals.
  • Hydroxocobalamin: Often used in injections and can be useful in certain medical conditions.


Our Co-Enzyme B Complex contains all eight B vitamins, including B12, in their daily recommended dosages. As with any supplement, consulting with your doctor or consulting with a registered dietitian can help you to find the supplement and dosage that is best for you and your specific circumstances.




Vitamin B12 plays an essential role in various bodily functions, from red blood cell formation to neurological health. Making sure that you get an adequate amount of vitamin B12 through a balanced diet that includes animal products or fortified foods is essential to prevent deficiency and its associated health risks. If you think you may have a deficiency in vitamin B12 or have specific dietary restrictions, consult with your doctor or a registered dietitian to determine the best way to meet your vitamin B12 needs through supplements or dietary adjustments. Prioritizing vitamin B12 intake can contribute significantly to your overall health and well-being.



Products mentioned in this post

Co Enzyme B Complex

Co Enzyme B Complex


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