What is Vitamin B-12?

Vitamin B-12, also known as cobalamin, is a water-soluble vitamin that is involved in the metabolism of every cell of the human body. It is an essential nutrient and has a key role in the normal functioning of our brain and the nervous system, as well as the production of red blood cells, DNA and RNA.

Vitamin B-12 is responsible for:

  • the formation and division of red blood cells

  • protecting the nervous system

  • synthesizing a person’s DNA

  • providing the body with energy


How is Vitamin B-12 created and stored in the body?

Vitamin B-12 cannot be produced by fungi, plants or animals. Only bacteria can manufacture this vitamin, as only bacteria have the enzymes needed for its synthesis. As the human body does not create vitamin B-12, we must get this nutrient from the bacteria in our diet.

When we consume food that contains Vitamin B-12, the hydrochloric acid in our stomach separates vitamin B-12 from the protein to which it is attached. Once the vitamin is separated, it combines with a protein made by the stomach called intrinsic factor and is absorbed by the body.

The amount of Vitamin B-12 that our body needs is very limited. In fact, in most healthy adults, the liver stores several years’ worth of vitamin B-12.


How much Vitamin B-12 do we need?

The recommended daily allowance (RDA) of B-12 depends on a person’s age:

  • Adults and teenagers: 2.4 micrograms (mcg) per day

  • Children between 9 and 13 years old: 1.8 mcg per day

  • Children between 4 and 8 years old: 1.2 mcg per day

  • Toddlers between 1 and 3 years old: 0.9 mcg per day

  • Infants between 7 and 12 months old require 0.5 mcg of B-12 per day, and babies less than 6 months old only need 0.4 mcg per day.

  • Pregnant women require 2.6 mcg, while breast-feeding women need 2.8 mcg per day.


Sources for Vitamin B-12:
Foods that can be fortified with vitamin B-12 include – fortified non-dairy milk, meat substitutes, breakfast cereals, nutritional yeast, vegan spreads, such as Marmite

It is essential to read the labels on all of these foods, to ensure that they are fortified with vitamin B-12.

Vitamin B-12 can be procured from certain non-vegetarian food sources as well, such as seafood (particularly clams, trout, salmon and tuna), beef, milk, and dairy products like yogurt and cheese as they are decaying substances and will contain bacteria. However, prolonged consumption of meat and dairy can result in the inability of the intrinsic cells in the stomach to absorb vitamin B-12.

Additionally, the quality and the toxins coming in through such foods, make fortified plant-based foods or supplements- a more preferred source for Vitamin B-12


Causes of Vitamin B-12 deficiency:

Even if a person gets enough vitamin B-12 in their diet, certain underlying health conditions can affect its absorption in the gut and lead to a vitamin B-12 deficiency.

The most common cause of vitamin B-12 deficiency in developed countries is impaired absorption due to a loss of gastric intrinsic factor (this is a glycoprotein produced by the stomach, necessary for the absorption of vitamin B-12), which must be bound to food-source B-12 in order for absorption to occur.

A vitamin B-12 deficiency can lead to both physical and psychological problems and impact a person’s mental health.

The following factors make a person more likely to have a vitamin B-12 deficiency:

  • alcohol abuse
  • Weakness and fatigue
  • certain medications, including antacids
  • eating a vegetarian or vegan diet
  • certain gastrointestinal disorders, such as Crohn’s disease & Celiac disease
  • People with gastrointestinal issues where the gastrointestinal tract that does not function normally may inhibit vitamin B-12 release or absorption.
  • weight loss surgery or other stomach surgery /gastric bypass or the removal of parts of the stomach, which can affect how the digestive system absorbs vitamin B-12
  • Aging- because a person becomes less able to absorb B-12 as they age. They can be affected by conditions that are linked to a decrease in stomach acid production, including inflammation in the stomach (atrophic gastritis).
  • Person having an endocrine-related autoimmune disorder, such as diabetes or a thyroid disorder.
  • Both diabetes and some medications for type 2 diabetes can increase the risk of vitamin B-12 deficiency.
  • These can decrease the production of acid and occasionally the digestive system can become overpopulated with bacteria that actually consume B-12, which essentially steal B-12 before it can be absorbed by the body. That condition is known as Small Intestinal Bacterial Overgrowth.
  • Vitamin C and potassium can also damage the structure of Vitamin B-12, so taking large doses of Vitamin C along with a source of B-12 can conceivably prevent its absorption which happens we consume multivitamin tablets.
  • Irradiation of fruits and vegetables
  • Pesticides used in farming
  • Frequent exposure to chlorine or other forms of sanitizing drinking water
  • Washing fruits and vegetables too much causing them to lose their inbuilt nutrients.
  • Preservatives used in packaged food
  • Modern day toothpastes with Triclosan which destroy oral bacteria
  • Overuse of the microwave


Symptoms of Vitamin B-12 deficiency:

Both vegans and non-vegans can suffer from B-12 deficiencies. Vegans may suffer because of low intake of vitamin B-12. Non-vegans suffer due to the inability to absorb B-12.

As vitamin B-12 deficiency shares many symptoms with other nutritional deficiencies and health conditions, it is possible that people may neither notice it nor get a diagnosis.

Common symptoms of a vitamin B-12 deficiency include:

  • nerve damage
  • weakness and fatigue
  • tingling in the hands and feet
  • numbness
  • blurred vision
  • fever
  • sweating
  • difficulty walking
  • problems with the digestive system
  • a sore tongue or mouth ulcers, swollen tongue, which may be pale yellow or very red
  • breathlessness
  • feeling faint or dizzy
  • depression
  • mood swings
  • pale skin
  • loss of appetite
  • tinnitus (ringing, buzzing, or hissing sounds in the ears)
  • decreased cognitive function, such as issues with memory, judgement or understanding
  • lethargy
  • constipation
  • irritability
  • headache
  • difficulty maintaining balance
  • heart palpitations
  • vision changes

Vitamin B-12 deficiency can occur in anyone at any age. B complex tablets contain B-12 but the amount of B-12 in them is not sufficient for proper supplementation.

Vitamin B-12 deficiency may be less common in the West, especially in the US, where soya milk and other ready-made foods are fortified with vitamin B-12. Many people who want to live naturally, are averse to taking vitamin B-12 supplements and this may not cause a problem for a number of years, since vitamin B-12 is stored in our body, but sooner or later this problem can catch up. Therefore it is important that everybody keeps a check.



Vitamin B12 deficiency prevention& management:

People who are deficient in vitamin B-12 can take supplements in the form of oral tablets, sublingual tablets that dissolve under the tongue, or injections

People who have trouble absorbing vitamin B-12 may need shots of the vitamin to treat their deficiency. Vitamin B-12 shots, rather than oral supplements, may be particularly helpful for people who have gastrointestinal issues because injections tend to bypass these areas.

Test for Vitamin B-12
Serum B-12 – The normal range is 200 to 900 pg/ml. (Please note that your B-12 may have been measured by another system – pmol/l so you should see the normal range described in your report.) If your B-12 is less than 150 it is very low. A good level is around 400. If a cyanocobalamin source (like spirulina or chlorella) is consumed these levels may be high but the B-12 is still not usable by the body. In this case it is better to rely on one of the other two tests: Homocysteine & Holotranscobalamin.

Serum B-12 – The normal range is 200 to 900 pg/ml.

50 ug twice a day OR 150 ug once a day OR 1000 twice a day OR 2,500 ug once a week

If Vitamin B12 deficiency is detected, supplementation with the appropriate dosage will be required to replenish the levels, as the RDA dosage may not be sufficient. Vitamin B12 supplements suitable for vegetarians and vegans are available these days. The right type of supplement and dosage can to be decided with the help of a healthcare professional.