Vitamin B12 Deficiency: Symptoms, Causes, and Treatment
January 28, 2025

A water-soluble vitamin B12 (cobalamin) is essential for many body processes. The body needs this vital component, which it cannot create on its own. Thus, it must be received through food or supplements.
The major functions of vitamin B12 are the synthesis of red blood cells, the upkeep of a healthy neurological system, and the metabolism of fats and proteins. In addition, it helps maintain brain function and aids in the creation of DNA. The improper absorption of this vitamin can lead to the body showing B12 deficiency symptoms.
What is Vitamin B12?
A vitamin that acts as the support system for the blood and nervous system is vitamin B12. Furthermore, it equally serves the purpose of producing DNA, a very crucial molecule that makes up every cell of the body. Consuming food and beverages containing vitamin B12 is advisable because the body is unable to produce vitamin B12 naturally. Animal products and drinks like meat, dairy, and eggs are one of the many foods that contain vitamin B12. Additionally, foods that have certain vitamins and minerals added to them, such as bread, nutritional yeast, and some cereals, are also fortified with it.
Vitamin B12 Deficiency
The synthesis of DNA, the building block of all cells, and the maintenance of nerve and red blood cells depend on vitamin B12. It also supports the neurological system.
If the body is not correctly absorbing vitamin B12 or is not getting enough of it through the diet, the chances of developing a curable vitamin B12 deficiency are high. A lack of vitamin B12, if not addressed, can cause anemia and harm to the brain and nerves. Initial symptoms often include depression, weakness, and constipation. Brain and nerve injury are other possible outcomes. Long-term harm might be irreparable. The usage of certain medications, food considerations, and underlying medical issues can all contribute to it.
Causes
A vitamin B12 shortage results from either consuming insufficient amounts of vitamin B12 or the body not correctly absorbing the vitamin B12. The following circumstances or ailments are the causes of vitamin B12 deficiency:
- Dietary deficiencies in vitamin B12: Individuals who do not consume enough naturally occurring vitamin B12-containing foods or foods fortified with B12 may show B12 deficiency symptoms.
- Gastritis: This condition involves inflammation of the lining of the stomach. A deficiency in vitamin B12 can develop when the stomach produces insufficient hydrochloric acid, which is necessary for its absorption.
- Pernicious Anaemia: This uncommon disease prevents people from producing protein in the stomach. The body cannot absorb the vitamin B12 without its inherent component. A vitamin B12 deficiency is seen in those who have pernicious anemia.
- Digestive disorders: Vitamin B12 absorption can be impaired by digestive conditions like Celiac disease and Crohn’s disease.
- Surgery: Patients who have undergone gastrointestinal surgery, such as a gastric bypass (a procedure used to lose weight), may find it difficult to absorb vitamin B12.
- Alcohol consumption disorder: This disorder can harm the digestive tract, resulting in a vitamin B12 deficiency.
- Transcobalamin II deficiency: A rare hereditary condition that affects how well vitamin B12 (cobalamin) is transported into the body
- Vitiligo
- Certain medications
Symptoms
Fatigue, sluggishness, depression, dyspnea, and nerve issues are some of the B12 deficiency symptoms. Some of the other symptoms are:
- Breathlessness: Breathlessness can also be a symptom of anemia caused by a vitamin B12 deficiency. This has to do with a rapid pulse and a deficiency of red blood cells.
- Elevated heart rate: One sign of vitamin B12 insufficiency might be a rapid heartbeat. To compensate for the body’s decreased red blood cell count, the heart may begin to beat more quickly.Â
- Tingling: A lack of vitamin B12 may result in a tingling feeling in the hands or feet. Vitamin B12 plays a role in producing myelin, a substance that insulates neurons and helps transmit sensations. Insufficient myelin makes nerves more vulnerable to injury. Peripheral nerves, or those in the hands and feet, are more prone to problems. Tingling in these body areas may be caused by injury to the peripheral nerves.
- Pale complexion: Jaundice, or pale and yellowing skin, can result from a vitamin B12 shortage. Insufficient production of red blood cells (RBCs) by the body might lead to these skin color alterations.
- Difficulties with walking: Damage to the peripheral nerves over time may result in issues with mobility, numbness in the feet and limbs, weaker muscles, and slower reflexes.Â
- Exhaustion: Fatigue may result from megaloblastic anemia caused by a vitamin B12 deficiency. An individual may feel very exhausted if the body does not have enough red blood cells (RBCs) to distribute oxygen.
- Mouth-ache: The following oral issues can result from a vitamin B12 deficiency and impact oral health:
- Glossitis, resulting in a smooth, red, swollen tongue
- An unpleasant aftertaste
- A burning feeling in the tongue
- Less oxygen reaches the tongue as a result of decreased red blood cell production, which causes these symptoms.
- Issues with logic or thinking: Doctors use the term cognitive impairment to refer to memory loss and difficulty with thinking that can arise from a vitamin B12 deficiency.
- Issues with mental health: A lack of vitamin B12 can hurt mood and increase the risk of mental health issues.
- Vomiting and diarrhea: Vitamin B12 deficiency may impact the digestive system. Insufficient red blood cells indicate insufficient oxygen delivery to the stomach. A person may feel unwell due to a lack of oxygen, which can further lead to diarrhoea.
- Loss of appetite and weight: Those who are deficient in vitamin B12 may experience nausea and other digestive issues that make them lose their appetite. Over time, a decreased appetite may result in weight reduction.
Treatment
The course of treatment may change based on the severity and underlying cause of the deficiency. Some of the popular treatment options are:
- Dietary modifications: Meat, fish, poultry, eggs, and dairy products are examples of animal products that are good dietary sources of vitamin B12.
- Vitamin B12 injections: These are commonly used in situations of severe shortage or problems with malabsorption. They work well because they directly help in raising blood levels.
- Nasal sprays: Nasal sprays are a wonderful option for those with malabsorption problems since they are a direct absorption type of supplement that enters the circulation.
- Oral supplements: These might be useful for those with lesser shortages or issues with absorption of vitamin B12.
Conclusion
When the body does not have enough vitamin B12 to operate correctly, the body starts showing B12 deficiency symptoms. It may result in several symptoms, such as anemia, tiredness, weakness, and neurological issues.
Inadequate dietary intake, intrinsic factor insufficiency, gastrointestinal diseases, and medicines are some of the reasons for B12 deficiency.
Contacting a doctor is crucial if the body starts displaying B12 deficiency symptoms.
Frequently Asked Questions
1. What symptoms indicate a low vitamin B12 level?
The majority of the time, weariness, lethargy, tingling feeling in the hands and feet, oral issues, disorientation, and irritability are the most typical vitamin B12 deficiency symptoms.
2. Is it possible for a vitamin B12 deficit to be fatal?
If left untreated, a deficit in vitamin B12 can cause significant harm to the brain system, increasing the chance of death. Pernicious anemia, a shortage in red blood cell synthesis brought on by a deficit in vitamin B12, can result in irreversible brain damage and even death.