Vitamin B12, chemically termed as Cobalamin is the last of the eight water-soluble vitamins that serves as a co-factor on DNA synthesis, amino acid metabolism and synthesis of fatty acids. It primarily aims towards the healthy functioning and development of the brain owing to its part in the synthesis of myelin, boosting the immune system and maturation of red blood cells in the bone marrow. Also Read: Vitamin B9: Functions, Food Sources, Deficiencies and Toxicity

vitamin B12 food sources

Vitamin B12 is naturally produced in certain types of bacteria and archaea that normally reside in the soil surrounded by grasses that are fed upon by certain mammals like cows and sheep that come under the ruminant category. The bacteria then proliferate within their body forms a part of their gut flora, gets absorbed in their muscle masses, passes through their body and again released into the soil producing more vitamin B12. Hence, the vitamin B12 is passed on to some fermented plant products and in milk, meat or eggs obtained from animals.

Our body usually absorbs vitamin B12 from the food in two distinct phases. In Phase 1, the hydrochloric acid present in the stomach detaches the vitamin B12 from the food that we eat. Whereas, in Phase 2, a protein secreted in the stomach known as intrinsic factor attaches itself to the B12 vitamin and hence helps in to get absorbed by the body.

Unlike other water-soluble vitamins, Cobalamin is one of the largest and structurally more complex than the rest. Each of the vitamers that compose vitamin B12 has potent physiological activity and also include rare element cobalt positioned in the centre of the corrin ring. Vitamin B12 is chemically available in four forms, cyanocobalamin, hydroxocobalamin, adenosylcobalamin and methylcobalamin.

Functioning mostly as a co-enzyme, i.e. helping in various enzyme-catalysed reactions, vitamin B12 was synthesized in the year 1972 by chemists Robert Burns Woodward and Albert Eschenmoser.


Vitamin B12 is a powerful neural compound that is extremely essential for the synthesis of neurotransmitters. It is also required for the proper growth, development and functioning of the brain and nerves, the formation of red blood cell, cell metabolism, and the production of DNA.

Being a potent brain compound, it plays a key role in treating and preventing psychotic conditions like Alzheimer’s, memory loss and dementia. It also slows down ageing, stimulates mood, improves mental function, and bolsters the immune system. Playing the role of a co-factor, it helps in the synthesis of neurotransmitters which in turn helps to regulate mood swings, prevent depression, mental disorders, schizophrenia, anxiety, pain and fatigue.

Regular intake of the B12 vitamin has shown to reduce homocysteine levels in the blood; a protein that is responsible for damaging arterial walls, an increase of which can cause heart ailments and elevated risk of hardening of arteries i.e. atherosclerosis. It also effectively reduces the risk of high triglyceride levels in the blood which causes a marked reduction of heart blocks and strokes. Also Read: World Heart Day: 5 Simple Ways To Care For Your Heart

Cobalamin is also important for treating conditions like diabetes, diabetic neuropathy, nerve damage in the hands or feet, weak bones (osteoporosis), swollen tendons, male infertility, insomnia, AIDS, inflammatory bowel disease, diarrhoea, asthma, allergies, a skin disease called vitiligo, and skin infections.

Vitamin B12, when taken via natural foods or supplements, helps produce healthy red blood cells and preventing conditions like anaemia. Along with folic acid, Vitamin B12 is also crucial to prevent the foetus from developing major congenital deformities of the brain or spine, including neural tube defects, such as spina bifida and anencephaly. Hence, women planning for pregnancy are advised to take vitamin B12 on prior consultation to prevent sudden miscarriages and evade these abnormalities in the foetus. 

Taken in adequate quantity, vitamin B12 helps to enhance bone health, increase bone density, bone mineralization and helps in the natural growth and remodelling of bones. It also reduces the risk of fracture, strengthens the bones, maintain overall body balance and provides the body with a strong and perfect skeletal structure.

Vitamin B12 also plays a key role in treating a host of ailments like age-related macular degeneration (AMD), cataracts, problems related to the mouth like gingivitis, canker sores, mouth ulcers, thyroid, Lyme disease, tinnitus, kidney and respiratory problems, etc. It also helps in reducing the risk of different types of cancer including breast cancer, uterine cancer, lung cancer, colon cancer, colorectal cancer and gall bladder cancer.

Cobalamin essentially promotes healthy hair, skin and nails. It improves the texture of the skin by preventing oxidative damage and treats various dermatological conditions. It rejuvenates and moisturises the skin, reduces various signs of ageing like wrinkles, fine lines, spots, dark circles, hyperpigmentation etc, making it crystal clear. In case of hair, and nails it prevents discolouration, maintains the natural colour of both hair and nails, and prevents them from being brittle and breaking. Also Read: 7 Ultimate Vitamins To Nourish Your Skin And Hair

Food Sources

The mood-control vitamin is extremely vital for the healthy functioning of the brain and body. Like any other water-soluble vitamins, this B12 vitamin also gets washed away from the body, hence one should consume a diet rich in vitamin B12 food choices to prevent the deficiency syndromes. And much to our respite, Mother Nature has blessed us with a bountiful amount of natural food sources loaded with this nutrient that suffices our daily requirements.

Following are the food sources high in vitamin B12:

Dairy products like yoghurt, milk and cheese.

Some fortified cereals, nutritional yeast, An algae product called nori, shitake mushrooms and certain animal sources like eggs, fish, clams, chicken, and meat are laden with vitamin B12.


Although vitamin B12 deficiency is quite uncommon in most of the developing nations, it’s not that rare. Lack of this essential nutrient can lead to severe symptoms causing vitamin B12 or cobalamin deficiency. Also Read: Vitamin B 12: Deficiency, Symptoms And Treatment

People who are following a vegan or vegetarian diet, have a decreased ability to absorb this vitamin due to low levels of hydrochloric acid in the stomach, take certain medication interaction or some gastrointestinal issues are more likely to deficiency syndromes.

Mostly cobalamin deficiency causes different types of anaemia and other neurodegenerative diseases. It is mostly characterized by signs and symptoms like weakness, fatigue, nerve damage, tingling sensations in the hands and feet, light-headedness, rapid heartbeat, rapid breathing and pale colour to the skin. It may also cause easy bruising or bleeding, blurred vision, fever, walking difficulties, gastrointestinal side effects including sore tongue, upset stomach, weight loss, diarrhoea, irritable bowel syndrome, flatulence and constipation.

If the lack of this healthful nutrient is not corrected on time it can lead to severe nerve and brain damage causing depression, disorientation and dementia.


Vitamin B12 though extremely necessary for healthy functioning of brain and nerve cells, over intake of vitamin B12 through food sources and supplements might be fatal to the body. The Recommended Dietary Intake is 2.4 mcg for adults, 1.8mcg for older children, 2.6 mcg for pregnant women and 2.8 mcg for lactating mothers. Anything more than the prescribed amount can cause severe allergic conditions like dizziness, anxiety, headache, nausea and vomiting.


An extremely healthful nutrient, vitamin B12 is necessary for the treatment of umpteen number of ailments including neural disorders, hyperlipidaemia, heart problems, skin infections, headaches, and insomnia. Hence, it is strongly advocated to use it within the prescribed quantity to steer clear of harmful side effects and enjoy the health benefits.