Vitamin B12, also known as cobalamin, is an essential water-soluble vitamin that plays a crucial role in various bodily functions. It is one of the eight B vitamins and is necessary for maintaining good health and proper functioning of the nervous system.




Function


Red Blood Cell Formation :- One of the primary roles of vitamin B12 is to aid in the formation and maturation of red blood cells in the bone marrow. Red blood cells are responsible for carrying oxygen from the lungs to various tissues and organs throughout the body. A deficiency in vitamin B12 can lead to decreased red blood cell production, resulting in a condition called megaloblastic anemia, where the red blood cells are larger and less functional.


Nervous System Health :- Vitamin B12 plays a crucial role in maintaining the health of the nervous system. It is involved in the synthesis of myelin, a fatty substance that coats and protects nerve fibers. Myelin allows nerve impulses to be conducted efficiently, facilitating proper nerve function and communication. Deficiency in vitamin B12 can lead to neurological symptoms, such as numbness or tingling in the extremities, difficulty walking, and memory problems.


DNA Synthesis :- Vitamin B12 is essential for DNA synthesis, which is crucial for cell division and replication. It is involved in the conversion of homocysteine (an amino acid) into methionine (another amino acid) and the synthesis of nucleotides, the building blocks of DNA. Adequate vitamin B12 levels are necessary for maintaining healthy cells and supporting tissue growth and repair.


Energy Production :- Vitamin B12 plays a role in the metabolism of carbohydrates, fats, and proteins. It helps convert these macronutrients into usable energy for the body. This is particularly important for maintaining overall energy levels and supporting various physiological processes.


Homocysteine Regulation :- Vitamin B12, along with  B6 and folic acid, helps regulate the levels of homocysteine in the blood. High levels of homocysteine have been associated with an increased risk of cardiovascular disease, and adequate levels of vitamin B12 are essential for keeping homocysteine levels in check.


Sources


Vitamin B12, also known as cobalamin, is an essential nutrient that plays a crucial role in the functioning of the nervous system and the production of red blood cells. It is primarily found in animal-based foods. Here are some common sources of vitamin B12 :-


1) Meat :- Beef, lamb, pork, and poultry are excellent sources of vitamin B12. Organ meats such as liver are particularly rich in B12.


2) Fish and Seafood :- Fish like salmon, trout, tuna, sardines, and clams are good sources of vitamin B12.


3) Dairy Products :- Milk, yogurt, and cheese contain vitamin B12, but the content can vary based on the processing methods and the diet of the animals.


4) Eggs :- Eggs, particularly the yolk, contain vitamin B12.


5) Fortified Foods :- Some plant-based foods are fortified with vitamin B12, making them suitable options for vegetarians and vegans. These may include fortified breakfast cereals, plant-based milk alternatives (soy milk, almond milk, etc.), and nutritional yeast.


6) Supplements :- Vitamin B12 supplements are available over-the-counter and can be used to meet dietary requirements, especially for individuals with dietary restrictions or absorption issues.


It's important to note that while plant-based foods like seaweed, algae, and fermented foods may contain some forms of B12, they usually provide inactive analogs of the vitamin, which may not be efficiently utilized by the human body. Therefore, it's essential for vegetarians and vegans to consider reliable B12 sources through fortified foods or supplements to prevent deficiencies.


Recommended dietary allowance


1) Infants (0-6 months) :- 0.4 micrograms (mcg) per day

2) Infants (7-12 months) :- 0.5 mcg per day

3) Children (1-3 years) :- 0.9 mcg per day

4) Children (4-8 years) :- 1.2 mcg per day

5) Children and Adolescents (9-13 years) :- 1.8 mcg per day

6) Teens (14-18 years) :- 2.4 mcg per day

7) Adults :- 2.4 mcg per day

8) Pregnant females :- 2.6 mcg per day

9) Breastfeeding females :- 2.8 mcg per day


Deficiency


Vitamin B12 deficiency occurs when there is an insufficient amount of vitamin B12 in the body to support its normal functions. This deficiency can lead to various health problems due to the crucial role that vitamin B12 plays in many physiological processes. Some of the common causes of vitamin B12 deficiency include :-


1) Inadequate Dietary Intake :- Vitamin B12 is primarily found in animal-based foods, so individuals following strict vegan or vegetarian diets without adequate supplementation may be at risk of deficiency.


2) Malabsorption Issues :- Some medical conditions can affect the absorption of vitamin B12 in the gastrointestinal tract. Examples include pernicious anemia (an autoimmune condition that impairs B12 absorption), celiac disease, Crohn's disease, and certain medications that interfere with B12 absorption.


3) Gastrointestinal Surgeries :- Surgeries that involve the removal or alteration of parts of the stomach or small intestine can disrupt the normal absorption of vitamin B12.


4) Aging :- As people age, their ability to absorb vitamin B12 from food may decline, increasing the risk of deficiency in the elderly population.


5) Chronic Alcoholism :- Alcohol can interfere with the absorption of vitamin B12 and also affect its utilization by the body.


Symptoms


  • Fatigue and weakness

  • Anemia (low red blood cell count)

  • Neurological symptoms like numbness, tingling, and difficulty walking

  • Cognitive issues, memory problems, and mood changes

  • Pale or yellowish skin

  • Glossitis (inflamed tongue)

  • Mouth ulcers

  • Digestive problems


If left untreated, vitamin B12 deficiency can lead to severe and potentially irreversible neurological damage. In some cases, it may result in pernicious anemia, a condition where the body does not produce enough healthy red blood cells, leading to fatigue and weakness.