Inadequate vitamin b12 can cause what type of anemia

Symptoms of anemia due to vitamin B12 deficiency or folate deficiency develop slowly and are similar to symptoms caused by other types of anemia, such as fatigue, weakness, and paleness. Vitamin B12 deficiency Vitamin B12 Deficiency Vitamin B12 deficiency can occur in vegans who do not take supplements or as a result of an absorption disorder. Anemia develops, causing paleness, weakness, fatigue, and, if severe, shortness... read more can also cause nerves to malfunction, causing tingling, loss of sensation, and muscle weakness. Severe vitamin B12 deficiency may cause confusion. In older people, anemia caused by vitamin B12 deficiency may be mistaken for dementia Dementia Dementia is a slow, progressive decline in mental function including memory, thinking, judgment, and the ability to learn. Typically, symptoms include memory loss, problems using language and... read more because of this symptom.

The most common cause of vitamin B12 deficiency is inadequate absorption. The following conditions can cause absorption to be inadequate:

• Surgery that removes the part of the small intestine where vitamin B12 is absorbed

• Repeated exposure to nitrous oxide (laughing gas)

• Decreased stomach acidity (common among older people)

Intrinsic factor may be lacking because abnormal antibodies, produced by an overactive immune system, attack and destroy the stomach cells that produce intrinsic factor—an autoimmune reaction called autoimmune metaplastic atrophic gastritis. Intrinsic factor may be lacking because the part of the stomach where intrinsic factor is produced was surgically removed. Vitamin B12 deficiency due to lack of intrinsic factor causes a type of anemia called pernicious anemia.

Among older people, absorption may be inadequate because stomach acidity is decreased. Decreased stomach acidity reduces the body’s ability to remove vitamin B12 from the protein in meat. However, the vitamin B12 found in vitamin supplements can continue to be well absorbed even in people with decreased stomach acid.

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