Vitamin B12 Deficiency

Vitamin B12 deficiency can cause several different problems such as a type of anemia called megaloblastic anemia that occurs when red blood cells can't develop properly; or the deficiency may cause neurological problems.

The symptoms due to the anemia include:

• fatigue (feeling tired most of the time)
• weakness in parts of your body
• loss of appetite
• weight loss
• constipation

The neurological symptoms of vitamin B12 deficiency may include any of these:

• numbness and tingling in your hands or feet
• loss of balance
• depression
• confusion and loss of memory
• burning pain or soreness of mouth or tongue

Some people can have the neurological symptoms without the anemia and all of these symptoms can come from other health problems. If you think you might have a vitamin B12 deficiency, you need to see a health care provider who can determine if you have a vitamin B12 deficiency by ordering special blood tests.

What causes vitamin B12 deficiency?Vitamin B12 is found in foods of animal origin (meat, fish, poultry, eggs and dairy products) so most people get enough from the foods they eat; however, some individuals can't absorb vitamin B12. Normally, when you eat food, the hydrochloric acid and digestive enzymes in your stomach release vitamin B12. Then the free vitamin B12 combines with a substance called intrinsic factor, which helps your small intestine absorb it.

People who have pernicious anemia can't produce the intrinsic factor to absorb enough vitamin B12. People with atrophic gastritis have decreased secretion of hydrochloric acid their stomachs and therefore also have decreased absorption of vitamin B12.

Diseases of the small intestine such as celiac disease or Chrohn's disease, some types of weight-loss surgery, parasitic infestations or bacterial overgrowth can also reduce a person's capability to absorb vitamin B12.

How is vitamin B12 deficiency treated? Vegans or individuals who eat very little foods of animal origin can take vitamin B12 as a dietary supplement or eat cereal fortified with it. People who have been diagnosed with a vitamin B12 deficiency due to malabsorption may be given regular vitamin B12 shots, which eliminate the need to absorb the vitamin through the small intestine, but in some cases taking the vitamin in a pill form may work.

It would be very difficult to use foods to prevent or treat vitamin B12 deficiencies due to malabsorption, although eating large amounts of liver was an historic treatment for pernicious anemia. If you're not sure if you're eating foods high in vitamin B12, this list may help:

• liver
• clams
• sardines
• fortified cereals
• trout
• salmon
• beefsteak

You will also find vitamin B12 in other foods, such as:

• milk and dairy products such as cheese, cream, sour cream and yogurt
• meat, fish and poultry
• eggs

_{Source: Office of Dietary Supplements, National Institutes of Health. "Dietary Supplement Fact Sheet: Vitamin B12." Accessed September 13, 2010. http://ods.od.nih.gov/factsheets/vitaminb12/.}