Home » What Causes Vitamin B12 Deficiency?

What Causes Vitamin B12 Deficiency?

In this post, you will figure out what causes vitamin B12 deficiency, what are symptoms and treatments, and which foods can help you get vitamin B12 naturally. 

B12 deficiency can be a consequence of different factors such as malabsorption, nutrient insufficiency, or inherent reasons.

Lack of vitamin B12 can lead to macrocytic anemia and neuropsychiatric disorders.  

If our bodies can’t absorb B12 for a long time, a shortage of this essential vitamin will take place.

What causes vitamin B12 deficiency can be three primary reasons as following:


1. Dietary Insufficiency

Your body stores surplus vitamin B12 in the liver. If your body can’t get this vitamin naturally from your diet for the long term, it will start to use the stored B12.

Here is where the deficiency will arise over time. 

2. Autoimmune

A study shows that the risk of B12 deficiency and anemia in people who suffer from autoimmune thyroid disease is higher than others.

3. Malabsorption

The absence of inherent factors can result in malabsorption of vitamin B12 in people who endure pernicious anemia. 

Also, gastric bypass surgery, damages to the small intestinal, or tapeworm infection can increase the risk of B12 deficiency.

Besides, any conditions related to ileal inadequate functioning, namely, tropical sprue, coeliac disease, and Crohn’s disease may bring about malabsorption and consequently B12 deficiency.

The vitamin B12 deficiency symptoms are

  • Fatigue
  • Pallor
  • Breathlessness
  • Dizziness
  • Irregular heartbeats
  • Weight loss
  • Sensations of Pins and
  • Needles
  • Numbness and tingling in feet and hands
  • The weakness of the muscles
  • Unsteady mobility
  • Mental block or carelessness
  • Visual disturbance

What Is Vitamin B12 Deficiency Treatment?

What Is Vitamin B12 Deficiency Treatment

You can treat the lack of vitamin B12 simply with either oral therapy or injections. 

But remember, you should stop the treatment in the below cases:

  • The level of this vitamin in your body becomes normal.
  • When a maximum of 5 injections is done. (Don’t inject more than five times to avoid adverse effects)
  • If symptoms get worsen by injections of vitamin B12
  • pregnancy

How To Get Vitamin B12 Naturally?

How To Get Vitamin B12 Naturally

The following are foods and fruits that are high in vitamin B12 that you can add to your daily diet to get B12 naturally.

1. Vitamin B12 Foods List

Here is a list of food that is rich in vitamin B12 according to the USDA (The U.S. Department of Agriculture).

  • Clams
  • Liver
  • Trout
  • Salmon
  • Tuna fish
  • Nutritional yeasts
  • Haddock
  • Beef
  • Milk
  • Yogurt
  • Cheese
  • Beef taco
  • Fortified breakfast cereal
  • Ham
  • Egg
  • Chicken


2. Vitamin B12 Foods For Vegetarians

Vitamin B12 Foods For Vegetarians

Here is the list of top foods high in vitamin B12 for vegetarians.

  1. Milk
  2. Cheese
  3. Yogurt
  4. Shitake mushroom
  5. Eggs
  6. Nori
  7. Fortified foods with vitamin b12 such as cereals
  8. Nutritional yeast

Ankar A, Kumar A. Vitamin B12 Deficiency (Cobalamin) [Updated 2019 Jan 11]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK441923/

Ness-Abramof, R., Nabriski, D. A., Braverman, L. E., Shilo, L., Weiss, E., Reshef, T., Shapiro, M. S., & Shenkman, L. (2006). Prevalence and evaluation of B12 deficiency in patients with autoimmune thyroid disease. The American journal of the medical sciences, 332(3), 119–122. https://doi.org/10.1097/00000441-200609000-00004




Wolffenbuttel, B., Wouters, H., Heiner-Fokkema, M. R., & van der Klauw, M. M. (2019). The Many Faces of Cobalamin (Vitamin B12) Deficiency. Mayo Clinic proceedings. Innovations, quality & outcomes, 3(2), 200–214. https://doi.org/10.1016/j.mayocpiqo.2019.03.002