Vitamin B12 Deficiency: What It Is & How to Treat It


Are you worried about symptoms like fatigue or numbness? Curious about the diagnostic procedures for B12 deficiency? Or perhaps you’ve heard controversial claims about the risks or benefits of B12 supplements and are unsure what to believe. We’ll tackle pressing questions such as “What happens if your vitamin B12 is low?” and “Is taking B12 every day good for you?” as well as delve into the relationship between B12 and various diseases, including neurological conditions and even cancer. For those on plant-based diets, there will be a special focus on how to get adequate B12 without animal products.

Welcome to our comprehensive guide on Vitamin B12, a nutrient that is crucial but often misunderstood. Despite its essential role in our health, from supporting neurological function to aiding in red blood cell production, there’s a surprising lack of awareness about vitamin B12. As a healthcare provider, you might be interested to know that deficiency in this vital nutrient is more common than many people think and can manifest in a wide range of symptoms and health issues. In this blog, we will dig deep into the intricacies of vitamin B12, from its function and sources to deficiency symptoms and treatment options.Whether you’re a healthcare professional or someone interested in optimizing your nutritional health, this blog aims to provide clear, evidence-based answers to all your B12-related queries. So, let’s start unraveling the vitamin B12 mystery.Vitamin B-12 deficiency is not common in the U.S as predominent population is meat eater.However, people who follow a vegetarian or vegan diet might be prone to deficiency because plant foods don’t contain vitamin B-12.Causes of Vitamin B12 Deficiency?


How do we absorb Vitamin B 12

Let us understand about how our body handles this Vitamin. Vitamin b12 is present in animal food only or unless our food is fortified. Vitamain B12 aborption starts in our Mouth. Our salivary glands produces a chemical called Heptocorin. It binds with vitamin and is passed to stomach. Our stomach lining has a very specialized cell called Parietal cells. These cells produce Hydocholoric Acid and Instric factor. In the presence of Acid, Instric factor binds to Vitamin B12 and is passed to small intestine where other pancreatic secretions combine with above complex. Then in the last part of intestine called Terminal Ileium B12 is absorbed.

So Vitamin B12 defciency can develop due to

  1. Insufficient Intake.
  2. Problems with Salivary Glands.
  3. Problem with Parietal cells in Grastric lining like atrophic gastritis, Gastric bypass or medication which decrease Acid Production like proton pump inhibitor. Also metform also interfere with aborption.
  4. Problems with Pancreatic Sections like Malaborption
  5. Diseases of Terminal Ileium like celiac disease
  6. Interferes with storge in liver


Why do we need Vitamin B12?

Vitamin B12 is needed for Red blood cells, Nerve cells  growth and replication and also for DNA repair. So it is clear that deficiency will lead to anemia due to red cell, neurological symptoms due to Nerve cell dysfunction. You age faster due to poor DNA repair.


Symptoms of Vitamin B12 Deficiency

  1. Fatigue: A notable symptom that can significantly impact daily life and activities.
  2. Weakness: Muscular strength often declines, affecting mobility and functionality.
  3. Numbness: A tingling or numbing sensation is commonly reported, particularly in the extremities like hands and feet.
  4. Anemia: A decrease in red blood cell count leading to pallor and diminished oxygen-carrying capacity.
  5. Cognitive: Issues such as memory loss, confusion, and difficulty in concentration can arise.
  6. Depression: Emotional changes, including persistent feelings of sadness or hopelessness, can occur.
  7. Imbalance: Issues with balance and coordination are common, affecting mobility.
  8. Vision: Optical disturbances, possibly leading to vision loss in extreme cases.
  9. Irritability: Mood changes and increased irritability are often noted.
  10. Digestive: Symptoms like constipation, loss of appetite, or weight loss may be present.
  11. Heart: Elevated levels of homocysteine can lead to cardiovascular issues.
  12. Neurological: More severe deficits can result in neurological symptoms like neuropathy and even paralysis in extreme cases.

Daily Recommened Dose of Vitamin B 12

Our Liver is the stores about 3-5 mg of Vitamin B12. We loose about 1 micirogram daily. We need to consume 2.4 microgram daily to replace daily losses aborption is very variable. This requirement will increase if you have any of the above diseases. It is recommended to take 50 micorgrams of Vitamin B12 or 2000 micrograms once a week dose.

Diagnosis and Treatment of Vitamin B12 Deficiency

Diagnosis and treatment of Vitamin B12 deficiency is very simple. Most of the time Your Primary care physician will Check your B12 on regualar basis. Usually No other specialies test is needed. Sometime we check other tests like MMA – methymelonic acid and Homocysteine Level. Follic Acid level should also be checked as it leads to similar symptoms.

The cutoff between normal vitamin B12 levels and deficiency varies by method and laboratory, but most laboratories define subnormal serum or plasma values as those lower than 200 or 250 pg/mL (148 or 185 pmol/L).Levels of serum methylmalonic acid (MMA), a vitamin B12-associated metabolite, are the most sensitive markers of vitamin B12 status, and an MMA level greater than 0.271 micromol/L suggests vitamin B12 deficiency. Another marker is total plasma homocysteine levels, which rise quickly as vitamin B12 status declines; a serum homocysteine level higher than 15 micromol/L, for example, suggests vitamin B12 deficiency.

Approximately 21% of adults older than 60 had abnormal levels of at least one vitamin B12 biomarker

How to prevent Vitamin B12 Anemia?

To prevent Vitamin B12 deficiency, include animal foods like poutary , meat, fish, and dairy in your diet. If you follow a vegan diet, consider taking B12 supplements. Fortified foods like breakfast cereals can also help. Discuss B12 supplementation with a healthcare provider and regularly monitor B12 levels, especially for high-risk individuals.Untreated vitamin B12 deficiency can lead to severe neurological (nervous system) damage, which can put an individual at a higher risk of mortality.

Which foods intake increase Vitamin B12 Level

When it comes to boosting your vitamin B12 levels, there are several food options to consider. Poultry, such as chicken and turkey, can be a great source of B12. Seafood, including fish and shellfish, contains high levels of this essential nutrient as well. Dairy products like milk, cheese, and yogurt also provide a good amount of B12. Eggs are another nutritious option to include in your diet. And if you’re looking for a convenient way to get your B12 intake, fortified breakfast cereals can be a great choice. By incorporating these foods into your meals, you can ensure that you’re getting an adequate amount of B12 to support your overall health and well-being.

Should you take a supplement?

Supplementation may be necessary for vegans or those with malabsorption issues. It’s important to discuss B12 supplementation with a healthcare provider and regularly monitor B12 levels. Always follow dosage guidelines provided by healthcare professionals.

Is there a risk of overdose?

Taking excessive amounts of b 12 vitamain generally not a concern, as it is a water-soluble vitamin that is excreted through urine. However, it’s important to follow the recommended dietary reference intakes (RDA) for B12 and consult a healthcare provider for personalized advice on intake. Higher doses may be necessary under medical supervision.


Vitamin b 12 deficiency occurs when the body lacks sufficient cobalamin, which is essential for red blood cell formation and proper nerve function. Symptoms of deficiency include weakness, fatigue, and numbness in the hands and feet. Treatment options include vitamin B12 injections, oral supplements with cyanocobalamin, and dietary changes. Those at risk include individuals with digestive disorders, vegans/vegetarians, and older adults. Regular testing helps prevent and manage deficiency anemia. Vitamin B12 plays a crucial role in metabolism, DNA synthesis, and cognitive function. It is important for lactation, as well as the health of the nervous and cardiovascular systems. While B12 deficiency can occur, especially in certain populations, it can be effectively managed through appropriate supplementation and dietary adjustments.Weight loss surgery may affect nutrient absorption in the small intestine. Neurology studies link low vitamin B levels to dementia. In health care, micrograms (mcg) are used to dose folic acid for megaloblastic anemia. Breastfeeding mothers should monitor folate deficiency. Excess homocysteine can indicate cardiovascular disease. B vitamins in yeast may reduce diarrhea. Blockers can interfere with nutrient uptake.


The content provided in this blog is intended for educational purposes only. It is crucial to understand that individual circumstances may vary, and a proper diagnosis is essential for effective treatment of vitamin B12 deficiency. The author and publisher of this blog cannot be held responsible for any adverse effects or consequences resulting from the use of information mentioned here. The reader must rely on the provided information solely at their own risk. It is important to consult with a healthcare professional for personalized advice on vitamin B12 deficiency and related conditions. Remember, pernicious anemia, a type of anemia caused by vitamin B12 deficiency, can have serious health implications, affecting the nervous system, cognition, and cardiovascular health. Proper nutrition, including foods rich in vitamin B12, along with medical guidance, can help prevent and manage deficiency. Use of dietary supplements and monitoring B12 levels is recommended under medical supervision.


Frequently Asked Questions

Who is at risk for developing a vitamin B12 deficiency?

Some individuals who are at a higher risk of developing a vitamin B12 deficiency include vegetarians and vegans, older adults with absorption difficulties, those with certain medical conditions like pernicious anemia or Crohn’s disease, and individuals who have undergone gastrointestinal surgery or take specific medications.

What are some treatment options for a vitamin B12 deficiency?

Treatment options for vitamin B12 deficiency include supplements, injections, and a diet rich in B12 sources like meat and dairy products. Supplements can be taken orally or sublingually, while injections may be necessary for severe deficiencies or if oral supplements are ineffective.

What is the prognosis (outlook) for vitamin B12 deficiency?

The outlook for vitamin B12 deficiency depends on its severity and underlying cause. If left untreated, it can lead to irreversible nerve damage and other complications. Treatment usually involves supplementation or dietary changes. With proper care, the prognosis is generally good, and symptoms can improve within weeks to months.

Is high vitamin B12 status a cause of lung cancer?

Some studies suggest a potential link between high vitamin levels and increased cancer risk, including lung cancer. However, there is no clear evidence that high vitamin B12 status directly causes lung cancer. It’s important to maintain healthy vitamin B12 levels through a balanced diet or supplements. Consult with a healthcare professional for personalized advice on vitamin B12 and cancer risk.

How do you know if you have a vitamin B12 deficiency?

Common signs of vitamin B12 deficiency include fatigue, weakness, numbness or tingling in the hands and feet, and difficulty walking. A blood test can confirm the deficiency. Risk factors include a vegetarian or vegan diet, gastrointestinal disorders, and certain medications. Treatment options may include supplements or injections of vitamin B12.

Can you get enough vitamin B12 from your diet alone?

While it is possible to obtain sufficient vitamin B12 from your diet alone, it can be challenging for certain individuals. Natural sources of B12 include meat, fish, and dairy products. Vegetarians, vegans, and those with specific medical conditions may need to consider supplementation or fortified foods.



In conclusion, Vitamin B12 deficiency can have serious health consequences if left untreated. It is important to be aware of the causes, symptoms, and treatment options available for this condition. If you suspect that you may be deficient in Vitamin B12, it is recommended to consult with a healthcare professional who can provide a proper diagnosis and suggest appropriate treatment. Additionally, incorporating foods rich in Vitamin B12 into your diet and considering supplementation under medical guidance can help prevent deficiency. Remember, subscribing to our newsletter will keep you updated on the latest information regarding Vitamin B12 deficiency and other health-related topics.



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