About Vitamin B12 Deficiency

What causes chronic Vitamin B12 deficiency?

There are various causes of Vitamin B12 deficiency, but they generally fall into any one of the following three categories:

1) Nutritional


  • Followers of a low protein diet are at risk for developing severe Vitamin B12 deficiency; the body is able to store Vitamin B12 for a few years at the most, so continued abstinence from B12-rich foods such as beef, liver, shellfish and cheese increases one’s chances of developing a deficiency of B vitamins.
  • Vegans are recommended to supplement with Vitamin B12 daily in order to avoid becoming deficient.
  • Senior citizens tend to eat lighter, less nutritious meals; Vitamin B12 deficiency in elderly citizens is therefore common.


2) Hereditary Malabsorption Syndrome


  • An antibody called ″the intrinsic factor″ is crucial for Vitamin B12 utilization, as it attaches itself to dietary Vitamin B12 and assists in absorption. The presence of intrinsic factor is determined by heredity, and those who are lacking it cannot access Vitamin B12 naturally from their food and risk becoming anemic.
  • Most sufferers of chronic Vitamin B12 deficiency are unaware of their condition until they receive a blood test; often complaints of continued fatigue or memory loss will prompt a physician to order a B12 deficiency screening.
  • For more on intrinsic factor, see, ″What is pernicious anemia?″ (Below)


3) Gastrointestinal


  • Gastric acids are crucial for Vitamin B12 absorption, as they draw Vitamin B12 from protein sources and aid in its digestion. Stomach acid production decreases with age, making senior citizens a high-risk category for anemia and dementia, along with other illnesses associated with Vitamin B12 deficiency.
  • Patients of gastric bypass or other forms of intestinal surgery are often at risk for developing a nutritional deficiency; an excessive amount of stomach acids are lost during the procedure which are crucial for absorbing Vitamin B12. Also, the presence within the intestinal walls of a ″competing″ bacterial host, often a side effect of gastrointestinal surgery, could result in low B12.
  • Antacid medication can interfere with proper Vitamin B12 absorption; sufferers of chronic acid indigestion who are on medication must supplement with B12 in order to avoid deficiency. Also, pregnant women who experience severe heartburn during their pregnancy should consider supplementing antacid tablets with Vitamin B12.
  • Certain genetic diseases cause irreparable damage to the intestines, thereby reducing one’s ability to efficiently absorb nutrients. Celiac disease patients are sensitive to gluten and must avoid it at all costs; exposure to foods containing gluten could result in severe malnourishment and injury to the intestinal walls. Crohn’s disease is another gastrointestinal condition; symptoms of Crohn’s disease include inflammation to the digestive tract, resulting in chronic diarrhea and undernourishment.


What are the symptoms of Vitamin B12 deficiency?

There are many signs which indicate nutritional deficiency of B12; often these symptoms are misdiagnosed as chronic depression, diabetes or stress, for example. A Vitamin B12 blood screening is crucial in order to obtain a proper analysis. Symptoms include, but are not limited to:

Physical Symptoms:


  • Weakness or fatigue
  • Muscular soreness
  • Impotence
  • Urinary or fecal incontinence
  • Shortness of breath
  • Headache
  • Nausea
  • Heartburn
  • Abdominal bloating


Psychological Symptoms:


  • Memory loss
  • Disorientation
  • Apathy
  • Irritability
  • Paranoia
  • Depression
  • Hallucinations
  • Violent behavior
  • Psychosis
  • Personality changes
  • Dementia


Neurological Symptoms:


  • Peripheral neuropathy: abnormal gait, impaired vibration or position sense, impaired pain or touch perception
  • Combined systems disease
  • Decreased reflexes
  • Unexplained vision or taste impairment
  • Electric-like shocks down the spine while rotating the head, also known as Lhermitte’s sign
  • Ataxia
  • Increased unsteadiness on feet while eyes are closed, also known as Romberg’s sign


Hematological Symptoms:


  • Megaloblastic anemia
  • Pancytopenia


Cardiovascular Symptoms:


  • Heart palpitations
  • Increased likelihood for heart attack and stroke


What is pernicious anemia?


  • Pernicious anemia, a form of Megaloblastic anemia, was first documented in the early 1900s as a then-fatal Vitamin B12 deficiency anemia.
  • Symptoms of pernicious anemia include extreme fatigue, shortness of breath, dizziness headache, and coldness in hands and feet and chest pain.
  • Anemia is a condition that occurs when there is insufficient hemoglobin in red blood cells to carry oxygen to cells and tissues.
  • Anemia can result from a variety of medical problems, including deficiencies of Vitamin B12, Vitamin B6, folate and iron.
  • Vitamin B12 deficiency anemia results from severe gastric atrophy, a condition which prevents gastric cells from secreting intrinsic factor.
  • Intrinsic factor is an antibody in the stomach which binds with Vitamin B12 and is necessary for vitamin absorption.
  • An absence of intrinsic factor prevents sufficient utilization of Vitamin B12 and eventually leads to pernicious anemia.


What is subacute combined degeneration (SCD)?


  • Associated with pernicious anemia, SCD is a deterioration of the spinal cord which is caused by severe Vitamin B12 deficiency.
  • SCD causes impairment to the brain, eyes and peripheral nerves
  • SCD damage can be irreversible if not detected in the early stages.
  • SCD symptoms vary between adults and children.


How do you test for Vitamin B12 deficiency?


  • A Vitamin B12 deficiency diagnosis can be obtained only through a blood screening performed by a physician.
  • A yearly blood test is often recommended for prevention.
  • Chronic conditions often require a monthly or bi-monthly screening.


What do doctors prescribe for Vitamin B12 deficiency?


  • B12 deficiency treatments may vary.
  • US RDA for Vitamin B12 is 6 mcg. per day.
  • The usual dose doctors prescribe for Vitamin B12 deficiency is 1,000 mcg.


Are you at risk?

If you belong to any one of the following groups then you are at risk for developing a Vitamin B12 deficiency disease:

  • Vegetarian and vegans
  • People over the age of 60
  • Individuals with pernicious anemia
  • Individuals with Chronic Fatigue Syndrome
  • Gastric bypass and gastrointestinal disorder patients
  • Athletes
  • Autoimmune disease patients
  • Chronic pancreatitis patients
  • Crohn’s disease patients
  • Individuals with malabsorption syndromes
  • Thyroid disease patients
  • Individuals with symptoms suggesting multiple sclerosis (ms4a)