What is Vitamin B12 Deficiency? Know Its Symptoms And Causes

Vitamin B12 Deficiency: This vitamin is necessary for the development of red blood cells, which transport oxygen throughout your body; a lack of it can cause weakness, anaemia, etc.

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A lack of vitamin B12 anaemia is a disorder in which your body does not produce enough healthy red blood cells as a result of a vitamin B12 deficiency. This vitamin is required for the formation of red blood cells, which transport oxygen throughout the body. A lack of red blood cells can reduce the flow of oxygen into tissues and the body. Because of the absence of oxygen, bodily functioning is likely to be compromised.

What Is Vitamin B12?

The Harvard School of Public Health defines Vitamin B12, or cobalamin, as a naturally occurring nutrient present in animal sources. It can also be mixed into dishes or used as a supplement. Vitamin B12 is required for the formation of red blood cells and DNA. It also plays an important role in the function and development of brain and nerve cells.

Vitamin B12 binds to the protein in our meals. Hydrochloric acid and enzymes in the stomach break down vitamin B12 into its free form. The vitamin B12 then binds to a protein called intrinsic factor, allowing it to be absorbed deeper down in the small intestine.

Supplements and fortified meals include free B12, which may be more easily absorbed. There are several vitamin B12 pills on the market. Although some believe that particular forms, such as sublingual tablets or liquids put beneath the tongue to be absorbed via the tissues of the mouth, have greater absorption than regular tablets, studies have not demonstrated a significant difference. Vitamin B12 pills are available in large doses considerably beyond the recommended dietary limit, however, even high doses are not always the amount that is absorbed since a suitable level of intrinsic factor is also required. Doctors may provide B12 injections in the muscle in situations of severe vitamin B12 insufficiency caused by insufficient intrinsic factors (pernicious anaemia).

What Are The Symptoms Of Vitamin B12 Deficiency?

According to the Harvard School of Public Health, the best approach to tell if someone is vitamin B12 deficient is not to measure vitamin B12 levels in the blood since some deficient individuals might have normal vitamin B12 levels. Homocysteine and methylmalonic acid levels in the blood are stronger indicators of true vitamin B12 activity than homocysteine. When there is a vitamin B12 deficit, these numbers rise. Up to 15% of the general population may be vitamin B12 deficient, according to estimates.

Since vitamin B12 is only present naturally in animal products such as meat, fish, poultry, and dairy, those who do not consume these foods run the danger of being deficient in them. Vegetarians have low blood levels of vitamin B, according to studies. 

What Are The Causes Of Vitamin B12 Deficiency?

According to the National Library of Medicine, an official US government source, there are three basic causes of vitamin B12 deficiency:

1. Autoimmune: Pernicious anaemia is an autoimmune disease characterised by the production of antibodies against intrinsic factors. 
   Anti-intrinsic factor antibodies bind to and impede the actions of intrinsic factors, preventing B12 absorption by the terminal ileum.
   
2. Malabsorption: Because parietal cells in the stomach manufacture intrinsic factors, every patient who has had gastric bypass surgery is at risk of acquiring a B12 deficit because their new alimentary tract skips the location of intrinsic factor production. Any injury to the terminal ileum, such as surgical resection owing to Crohn's disease, will limit B12 absorption and lead to a shortfall in individuals with normal intrinsic factor production. Other small intestine damage, such as celiac disease inflammation or infection with the tapeworm Diphyllobothrium latum, can also cause B12 insufficiency.
3. Dietary Insufficiency: Although vitamin B12 is stored in excess in the liver, people who have maintained a rigorous vegan diet for three years or more may acquire a B12 shortage due to a lack of food intake.

What Are The Possible Treatments And Management? 

According to the National Library of Medicine, an official US government source, B12 replenishment therapy is used to treat vitamin B12 deficiency. However, the length and mode of therapy differ depending on the cause of the deficit.

In patients who are deficient owing to a strict vegan diet, an oral B12 supplement is sufficient for replenishment.

A parenteral dosage of B12 is indicated in patients with intrinsic factor insufficiency, whether from pernicious anaemia or gastric bypass surgery because oral B12 will not be effectively absorbed owing to the lack of intrinsic factor. Once a month, an injectable dosage of 1000 mcg of B12 is advised. In newly diagnosed individuals, 1000 mcg of B12 is administered intramuscularly once a week for four weeks before moving to a once-monthly dosage. Despite the lack of intrinsic factors, studies have demonstrated that oral B12 is efficacious at dosages high enough to fully saturate intestinal B12 receptors.

Routine B12 monitoring should be undertaken in anybody who is at risk of developing a B12 deficit, such as people with Crohn's disease or celiac disease. Therapy is initiated if the disease's severity worsens and B12 levels begin to fall. Prophylactic medication before B12 levels decline, on the other hand, is not recommended.