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Vitamin B12 Deficiency

Vitamin B12 Deficiency: Introduction

Vitamin B12 deficiency is a lack of a sufficient amount of vitamin B12 in the body that for optimal health. Vitamin B12 deficiency is a common condition that can result in vitamin B12 deficiency anemia, also known as pernicious anemia.

Vitamin B12 deficiency is caused by an inability of the body to absorb vitamin B12 or a lack of vitamin B12 in the diet. Vitamin B12 is essential for many aspects of health, including the production of red blood cells in the blood.

Vitamin B12 deficiency can be serious if untreated, because it can lead to decreased production of red blood cells in the blood. Healthy amounts of red blood cells are necessary for the proper delivery of necessary oxygen to the body's cells and tissues. A lack of sufficient amounts of red blood cells due to vitamin B12 deficiency results in a serious complication called vitamin B12 deficiency anemia or pernicious anemia.

Symptoms of vitamin B12 deficiency include very pale skin, shortness of breath and fatigue. For more details on symptoms and complications, see symptoms of vitamin B12 deficiency.

Vitamin B12 deficiency can also affect normal growth and development, the production of nerves, skin, hair and genes and normal metabolism.

Vitamin B12 is a water soluble vitamin that must be ingested and absorbed daily in order to avoid vitamin B12 deficiency and maintain health. Vitamin B12 is taken into the body by eating certain foods, including lean red meats, poultry, fish, and dairy products, such as milk, cheese and yogurt. In some cases, vitamin B12 deficiency can occur when a person does not eat enough foods that contain vitamin B12, such as someone who follows a vegan diet.

Most often a vitamin B12 deficiency occurs when the body is unable to absorb vitamin B12 from ingested foods. Problems with the absorption of vitamin B12 can occur due to conditions that affect the absorption of the vitamin in the small intestine, such as celiac disease, Crohn's disease, or surgical removal of a portion of the small intestine.

Most often, the condition is caused by a lack of intrinsic factor, a protein substance that is produced by the stomach and is necessary for the absorption of vitamin B12 in the small intestine. A lack of intrinsic factor can be due to a surgical procedure that removes all or part of the stomach. It may also be caused by an autoimmune response that destroys intrinsic factor or the stomach cells that produce intrinsic factor. Less often, some people may be born with an inherited inability to make enough intrinsic factor.

A diagnosis of vitamin B12 deficiency begins with taking a thorough personal and family medical history, including symptoms, and a physical examination. Diagnostic tests include a complete blood count (CBC), which measures the numbers of the different types of blood cells in the blood. A serum vitamin B12 level measures levels of the vitamin in the blood. In addition, tests will be performed to determine the cause of vitamin B12 deficiency, including diseases that can underlie vitamin B12 deficiency.

Because the symptoms and presentation of vitamin B12 deficiency can take years to develop, it is possible to that a diagnosis can be missed or delayed. For information on misdiagnosis, refer to misdiagnosis of vitamin B12 deficiency.

Vitamin B12 deficiency can usually be treated successfully, and most people with the disorder have a good prognosis. Treatment of vitamin B12 deficiency involves vitamin B12 injections. Treatment is tailored to the individual case, the cause, and the presence of any underlying diseases or complications. For more information on treatment, refer to treatment of vitamin B12 deficiency. ...more »

Vitamin B12 Deficiency: A deficiency of Vitamin B12 primarily causes anemias the body is unable to make sufficient quantities of normal red blood cells. Severe cases can lead to permanent nervous system problems. The vitamin B12 deficiency can result from absorption problems, insufficient dietary intake, certain medications (e.g. metformin), inherited conditions (e.g. transcobalamin deficiency) and certain chronic parasitic intestinal infestations. More detailed information about the symptoms, causes, and treatments of Vitamin B12 Deficiency is available below.

Vitamin B12 Deficiency: Broader Related Topics


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