What is cobalamin?

Cobalamin is one of the B complex nutrients, specifically vitamin B12. Cobalamin gets its name from its derivative, cobalt. Your body is able to absorb four types of cobalamin- cyanocobalamin, hydroxocobalamin, methylcobalamin, and adenosylcobalamin.

Cyanocobalamin is the type of vitamin B12 found in protein-based foods like beef, chicken, organ meats, shellfish, and dairy products. Many vitamin B12 supplements in the US use cyanocobalamin for optimum digestion and low cost.

Hydroxocobalamin is a popular form of vitamin B12 used by European supplement manufacturers. It is also used to treat cyanide poisoning.

When you ingest cyanocobalamin or hydroxocobalamin, your body instantly converts it into different forms of vitamin B12, methylcobalamin, and adenosylcobalamin. Now fully absorbed, you benefit from all the necessary biochemical properties of vitamin B12, including increased stamina, enhanced cognitive functioning, and a healthy nervous system.

Cobalamin and the vegan diet

As mentioned earlier, vitamin B12 (cobalamin) occurs exclusively in animal-based foods; lean beef, chicken liver, turkey breast, clams, oysters, halibut, caviar, and Swiss cheese are all excellent sources of cobalamin.

If you follow a strict vegan diet or if you’re a vegetarian and rarely eat fish or dairy products, then you must supplement with cobalamin in order to avoid getting vitamin B12 deficiency, a condition which affects your nervous system, cognitive health, mood, and metabolism.

Contrary to some opinions, there are very few natural sources of vegan vitamin B12, and none have adequate amounts of cobalamin to sustain good health. Dried seaweed (nori) supplies some vitamin B12, but in trace amounts.

Risk factors for cobalamin deficiency

Besides following a vegan diet, other factors exist that affect your chances for suffering from vitamin B12 (cobalamin) deficiency, such as lifestyle choices, illnesses, and certain medications.

Risk factors for cobalamin deficiency include:

  • Pernicious anemia, an illness that inhibits absorption of cobalamin
  • Family history for cobalamin deficiency
  • History of autoimmune disorders
  • Gastrointestinal disorders, such as Crohn’s disease, celiac, GERD, and irritable bowel syndrome (IBS)
  • Previous gastrointestinal surgery to correct digestive problems
  • Previous bariatric surgery, including gastric bypass
  • Using medications such as protein pump inhibitors (PPIs) for GERD, or metformin for diabetes
  • Alcoholism
  • Old age
  • H pylori infection


Why is cobalamin deficiency so widespread?

Vitamin B12 (cobalamin) deficiency is one of the most common forms of malnutrition in wealthy, developed countries. Unfortunately, cobalamin deficiency is an illness that often slips under the radar, as the symptoms mask themselves as other comorbid conditions. (For example, when depression occurs with cobalamin deficiency, doctors rarely think to check vitamin B12 levels.)

Since cobalamin deficiency symptoms can take years to manifest, and since physicians don’t routinely run vitamin B12 blood tests, most people don’t know they have depleted their cobalamin stores until they start to notice severe symptoms of cobalamin deficiency, usually around middle-age.

Sometimes, cobalamin is an autoimmune disorder. Pernicious anemia is one cause of vitamin B12 deficiency that sometimes results from an improper immune system reaction to intrinsic factor, a digestive enzyme crucial for cobalamin absorption.

As the propensity for acquiring autoimmune disorders rises, as we’ve seen in recent trends, so do the incidents of autoimmune cobalamin deficiency rise in accordance.

Why cobalamin blood tests don’t work

Another explanation for the progression of cobalamin deficiency has to do with the efficiency of blood testing.

When you absorb cobalamin, only a small amount enters the blood stream and gets to work on protecting your nerve cells, producing energy, and regulating red blood cell distribution. The majority of cobalamin that enters your body goes to your liver, where it is stored for years in a dormant state.

The former type of cobalamin is “active vitamin B12,” where the latter is “unusable” cobalamin that has no impact on your current health whatsoever.

Here’s the clincher: when your doctor tests for serum vitamin B12, he is actually measuring the amount of total vitamin B12 units in your body, not the amount of active cobalamin, since cobalamin blood tests don’t differentiate between active and unusable vitamin B12.

So, a lab result that indicates normal levels of cobalamin may be a false result, as it doesn’t take into account that you may have depleted your stores of usable cobalamin, indicating severe vitamin B12 deficiency, regardless of the amounts of cobalamin in your liver.

Symptoms of vitamin B12 (cobalamin) deficiency

Historically, cobalamin deficiency (pernicious anemia) was a fatal disease. Today, we understand that prompt supplementation of cobalamin can prevent death or severe damage and loss of nerve cells.

The best way to catch cobalamin deficiency is to recognize the symptoms early on, before they have a chance to progress further.

Here are some common symptoms of cobalamin deficiency:

  • Constant fatigue
  • Memory problems
  • Depression
  • Aggressive behavior
  • Paranoia
  • Painful numbness and tingling in the hands and feet
  • Face twitching, especially in one eye
  • Vision problems
  • Difficulty walking
  • Frequently dropping things
  • Difficulty swallowing


Treatment for vitamin B12 deficiency

If your doctor diagnoses vitamin B12 deficiency, then he will prescribe cobalamin supplements. Usually, the patient receives cyanocobalamin sublingual tablets or vitamin B12 shots until symptoms abate.

Sometimes, cobalamin shots alone aren’t enough. You may feel tired and achy long before you are due for your next round of vitamin B12.

This is when it helps to supplement with extra over-the-counter (OTC) vitamin B12, in addition to (or in place of) cobalamin injections.