Vitamin B12 Deficiency-Know the Symptoms and how to avoid them?

Vitamin B12 RICH FOODS
Vitamin B12 RICH FOODS

Know the significance of Vitamin B12 in the body, sources, deficiency and underlying symptoms

Vitamin B12 is a water-soluble vitamin that is naturally present in some foods, added to others, and available as a dietary supplement and a prescription medication. Since vitamin B12 contains the navy blue mineral Cobalt, compounds with vitamin B12 activity. This collectively becomes Cobalamins. Vitamin B12 is a must for the development, and function of the central nervous system, healthy RBC formation; and DNA synthesis. If Fatigue, Headaches, Depression and Gastrointestinal issues are there, Vitamin B12 deficiency is confirmed. The process of absorption starts in the mouth when food mixes with saliva. More vitamin B12 is released from its food matrix by the activity of hydrochloric acid and gastric protease in the stomach, where it then binds to the ingestion of food. Here is a video that illustrates the significance of Vitamin B12. Vitamin B12 is absorbed in the body in following stages.

Vitamin B12 Absorption

Importance of Vitamin B12

Vitamin B12 Dosage-How much Vitamin B12 you need per day?

  • RDA (Recommended Dietary Allowance) – The Recommended Dietary Allowance for men and women ages 14 years and older is 2.4 micrograms daily. For pregnancy and lactation, the daily amount increases to 2.6 mcg and 2.8 mcg daily, respectively.
  • Ul (Upper Intake Level) – A Tolerable Upper Intake Level (UL) is the maximum daily dose unlikely to cause adverse side effects in the general population. No upper limit has been set for vitamin B12, as there is no established toxic level.  However, some evidence suggests that supplements of 25 mcg per day or higher may increase the risk of bone fracture.

Vitamin B12 Food Source

Fish and Shellfish

  • Cooked clams: 84.1 micrograms
  • Steamed mussels: 20.4 micrograms
  • Cooked Atlantic mackerel: 16.1 micrograms
  • Steamed Alaska king crab: 9.8 micrograms
  • Cooked wild rainbow trout 5.4 micrograms
  • Cooked salmon: 2.4 micrograms
Vitamin B12
Vitamin B12


Cows also pass B12 into their milk. This is what you’ll find in the following:

  • Low-fat milk, 1 cup: 1.2 micrograms
  • Low-fat yogurt, 8 ounces: 1.2 micrograms
  • Swiss cheese, 1 ounce: 0.9 micrograms


Eggs- If you have a deficiency, eggs known to raise your Vitamin B12 levels.  

Plant based Sources of Vitamin B12

You can get B12 from some plant-based sources. These include fortified foods with added nutrients.

  • Fortified non-dairy milk, such as soy or oat, 1 cup: 0.6-2.07 micrograms
  • Fortified cereals, one serving: 0.6-2.1 micrograms
  • Nutritional yeast, 1 tablespoon: 4.8 micrograms

Signs of Deficiency to find Vitamin B12

Measuring vitamin B12 in the blood is actually not the best way to determine whether someone is deficient, as some people with a deficiency can show normal B12 blood levels. Blood levels of methylmalonic acid, a protein breakdown product, and homocysteine are better markers that capture actual vitamin B12 activity. These values increase with a vitamin B12 deficiency. It is estimated that up to 15% of the general population has a vitamin B12 deficiency.

What Factors cause Vitamin B12 deficiency?

  • Lack of animal products such as milk
  • Medications that decrease Stomach Acid
  • Intestinal surgeries or disorders that disrupt absorption

What are the Health Risks of Excessive Vitamin B12?

The low potential for toxicity in Vitamin B12 did not establish an Upper intake label. Even at large doses, vitamin B12 is generally considered to be safe because the body does not store excess amounts.

Also read: Vitamin D causes weight loss