Vitamin B12 Deficiency

Although a vitamin B₁₂ deficiency is easily treatable, it can cause permanent nerve damage if left untreated. Possible signs of a deficiency include constipation, loss of appetite, fatigue, and problems with balance. Certain people are at an increased risk for developing a vitamin B₁₂ deficiency, including those who are strict vegetarians, have cancer, or have liver or kidney disease.

Vitamin B12 Information

What Is Vitamin B12 Deficiency?

Vitamin B₁₂ deficiency is fairly common, at least compared to many other vitamin deficiencies. Some people are at a much higher risk for a deficiency, compared to others. Although a vitamin B₁₂ deficiency is easily treatable, it can cause permanent damage if left untreated.

Possible Signs of Vitamin B12 Deficiency

Signs of a vitamin B₁₂ deficiency may include:

Anemia
Fatigue
Weakness
Weight loss and loss of appetite
Constipation
Numbness or tingling (or other strange sensations) in the hands or feet
Problems with balance
Depression
Confusion or dementia
Poor memory
Soreness of the mouth or tongue
Failure to thrive and delayed development (in infants).

The nerve damage caused by this deficiency may be permanent, even after it is corrected. Folic acid can "mask" a vitamin B₁₂ deficiency, making it more difficult to detect and diagnose. Although folic acid can correct anemia due to a vitamin B₁₂ deficiency, it does not prevent the nerve damage that a deficiency can cause.

Who's at Risk?

Most people in developed countries consume plenty of vitamin B₁₂. However, people can have problems absorbing the vitamin from their diets. People at an increased risk for vitamin B₁₂ deficiency include:

Strict vegetarians
Infants of mothers with vitamin B₁₂ deficiencies (especially exclusively breastfed infants)
Older adults
People who have had surgery to remove parts of the digestive tract (especially the stomach or small intestines)
People with the following medical conditions:

Pernicious anemia
Inflammatory bowel disease (especially Crohn's disease)
Sprue (such as celiac sprue)
Kidney disease
Liver disease
An overactive thyroid (hyperthyroidism)
Cancer.

Treating a Vitamin B12 Deficiency

As you might guess, taking vitamin B₁₂is effective for treating a deficiency. It is also effective for preventing a deficiency in people at high risk for such problems. Although it was once thought that injections were the only way to treat vitamin B₁₂ deficiencies due to low or absent intrinsic factor, it is now known that oral forms can be just as effective as injectable forms, although much higher doses are required. Small amounts of vitamin B₁₂ can be absorbed after oral consumption, even without any intrinsic factor. Many healthcare providers choose to initially treat with injections to build up the stores of vitamin B₁₂ in the body and then follow with oral supplementation.