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"What symptoms indicate a vitamin B-12 deficiency?"

ZocdocAnswersWhat symptoms indicate a vitamin B-12 deficiency?


I'm a lactose-intolerant woman who doesn't eat meat very often, so I'm starting to worry that I'm becoming deficient in vitamin B-12. How would I know if I were deficient? What are the first symptoms?


Vitamin B12 (cobalamin) deficiency can have many different causes, and the specialists involved in diagnosis and treatment include internists, neurologists, gastroenterologists, and others. Animal products (meat and dairy) provide the source of vitamin B12 for humans and much of it is stored in the liver. Dietary vitamin B12 is liberated to a more available form by stomach acids then bound a secreted factor which creates a more absorbable form. This form is then absorbed in the small intestine, specifically the ileum (or the last part of the small intestine).

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Problems with this factor or the ileum may also lead to vitamin B12 deficiency. There are various symptoms of vitamin B12 deficiency and may occur based on the severity. Mild vitamin B12 deficiency may not result in any symptoms but could be evidence in routine blood tests, such as the hematocrit, suggesting anemia with abnormal appearing white blood cells. Early vitamin B12 deficiency may also manifest as simply malaise and fatigue although these nonspecific symptoms can be the result of other vitamin/mineral deficiencies (such as iron deficiency, etc). Additional neurological symptoms include memory loss, irritability, and potentially dementia. Severe vitamin B12 deficiency can also cause a sense of imbalance large from improper sensation. If you have symptoms concerning for vitamin B12 deficiency, your doctor can check a vitamin B12 level in your blood-work. It is not possible to come to a diagnosis without examining the patient. The strong recommendation is to see your internist and get evaluated in person.

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